RESUMEN
INTRODUCTION: Neoadjuvant endocrine therapy (NET) is recommended for the treatment of invasive breast cancer (BC), particularly luminal subtypes, in locally advanced stages. Previous randomized studies have demonstrated the benefits of aromatase inhibitors in this context. However, NET is typically reserved for elderly or frail patients who may not tolerate neoadjuvant chemotherapy. Identifying non-responsive patients early and extending treatment for responsive ones would be ideal, yet optimal strategies are awaited. AIMS: This non-randomized phase 2 clinical trial aims to assess NET feasibility and efficacy in postmenopausal stage II and III luminal BC patients, identifying predictive therapeutic response biomarkers. Efficacy will be gauged by patients with Ki67 ≤ 10% after 4 weeks and Preoperative Endocrine Prognostic Index (PEPI) scores 0 post-surgery. Study feasibility will be determined by participation acceptance rate (recruitment rate ≥50%) and inclusion rate (>2 patients/month). METHODS: Postmenopausal women with luminal, HER2-tumors in stages II and III undergo neoadjuvant anastrozole treatment, evaluating continuing NET or receiving chemotherapy through early Ki67 analysis after 2 to 4 weeks. The study assesses NET extension for up to 10 months, using serial follow-ups with standardized breast ultrasound and clinical criteria-based NET suspension. Clinical and pathological responses will be measured overall and in the luminal tumor A subgroup. Toxicity, health-related quality of life, and circulating biomarkers predicting early NET response will also be evaluated.
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Anastrozol , Neoplasias de la Mama , Estudios de Factibilidad , Terapia Neoadyuvante , Humanos , Anastrozol/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Femenino , Terapia Neoadyuvante/métodos , Persona de Mediana Edad , Posmenopausia , Antineoplásicos Hormonales/uso terapéutico , Anciano , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Antígeno Ki-67/análisis , Antígeno Ki-67/metabolismo , Adulto , Ensayos Clínicos Fase II como AsuntoRESUMEN
BACKGROUND: The MONALEESA7 and 2 phase 3 randomized trials demonstrated a statistically significant progressionfree survival (PFS) and overall survival (OS) benefit with initial ribociclib + endocrine therapy (ET) versus placebo + ET in pre and postmenopausal patients with hormone receptorpositive (HR+)/human epidermal growth factor receptor 2negative (HER2−) advanced breast cancer (ABC), respectively. Similar trends were observed in Asian subgroup analyses. This phase 2 bridging study of initial ET + ribociclib enrolled pre and postmenopausal patients with HR+/HER2 ABC from China and was conducted to demonstrate consistency of PFS results in a Chinese population relative to the global MONALEESA7 and 2 studies. METHODS: Patients were randomized (1:1) to ET (nonsteroidal aromatase inhibitor + goserelin for premenopausal patients; letrozole for postmenopausal patients) + either ribociclib or placebo. The primary endpoint was investigatorassessed PFS. RESULTS: As of April 25, 2022, the median followup was 34.7 months in both cohorts. In the premenopausal cohort, median PFS was 27.6 months in the ribociclib arm (n = 79) versus 14.7 months in the placebo arm (n = 77) (hazard ratio 0.67 [95% CI: 0.45, 1.01]). In the postmenopausal cohort, median PFS was not reached in the ribociclib arm versus 18.5 months in the placebo arm (n = 77 in each arm) (hazard ratio 0.40 [95% CI: 0.26, 0.62]). Data also suggested improvements in secondary efficacy endpoints, although OS data were not mature. The safety profile in this population was consistent with that in global studies. CONCLUSIONS: These data demonstrate a favorable benefitrisk profile for ribociclib + ET in Chinese patients.
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Aminopiridinas , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama , Letrozol , Posmenopausia , Purinas , Receptor ErbB-2 , Receptores de Estrógenos , Humanos , Aminopiridinas/administración & dosificación , Aminopiridinas/uso terapéutico , Aminopiridinas/efectos adversos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Purinas/administración & dosificación , Purinas/efectos adversos , Persona de Mediana Edad , Receptor ErbB-2/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Receptores de Estrógenos/metabolismo , Letrozol/administración & dosificación , Letrozol/uso terapéutico , Adulto , China , Anciano , Receptores de Progesterona/metabolismo , Premenopausia , Supervivencia sin Progresión , Goserelina/administración & dosificación , Goserelina/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/uso terapéutico , Pueblos del Este de AsiaRESUMEN
Polycystic ovary syndrome (PCOS) is one of the leading causes of infertility in women. Animal models are widely used to study the etiologic mechanisms of PCOS and for related drug development. Letrozole-induced mouse models replicate the metabolic and reproductive phenotypes of patients with PCOS. The traditional method of letrozole treatment in PCOS mice requires daily dosing over a certain period, which can be labor-intensive and cause significant stress to the mice. This study describes a simple and effective method for inducing PCOS in mice by implanting a controlled letrozole-releasing mini-pump. A mini-pump capable of stable, continuous release of a quantitative amount of letrozole was fabricated and implanted subcutaneously in mice under anesthesia. This study demonstrated that the mouse model successfully mimicked PCOS features after letrozole mini-pump implantation. The materials and equipment used in this study are readily available to most laboratories, requiring no special customization. Collectively, this article provides a unique, easy-to-perform method for inducing PCOS in mice.
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Ratones , Síndrome del Ovario Poliquístico , Síndrome del Ovario Poliquístico/inducido químicamente , Letrozol/administración & dosificación , Femenino , Implantes de Medicamentos , Inhibidores de la Aromatasa/administración & dosificaciónRESUMEN
PURPOSE: To summarize the findings of relevant randomized controlled trials (RCTs) and conduct a meta-analysis to investigate the potential effect of aromatase inhibitors on preventing moderate to severe ovarian hyperstimulation syndrome (OHSS) in infertile women undergoing in vitro fertilization (IVF). METHODS: We searched for relevant RCTs in electronic databases, including MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov (from inception to August 2023). In addition, we manually searched the related reviews and reference lists of included studies for further relevant studies. We included RCTs where aromatase inhibitors prescribed either during controlled ovarian stimulation (COS) or in early luteal phase. The meta-analysis was performed using RevMan 5.4.1 software. The primary outcome was the incidence of moderate to severe OHSS. A descriptive analysis was conducted in cases where a meta-analysis was not feasible due to heterogeneity or lack of comparable data. RESULTS: 2858 records were retrieved and 12 RCTs were finally included. Letrozole was administered in the treatment group during COS in seven RCTs, whereas in the early luteal phase in five RCTs. Compared with the control group, the risk of moderate to severe OHSS significantly reduced by 55% in the letrozole group (RR 0.45, 95% CI 0.32 to 0.64, I2 = 0%, 5 RCTs, 494 patients). Moreover, serum estradiol (E2) levels on hCG trigger day significantly decreased with the administration of letrozole during COS (MD -847.23, 95% CI -1398.00 to -296.47, I2 = 93%, 5 RCTs, 374 patients). And serum E2 levels on the 4th, 5th and 7th to 10th day after hCG trigger were also significantly lower than those in the control group when letrozole was administered in the early luteal phase. CONCLUSIONS: Patients with high risk of OHSS probably benefit from letrozole, which has been revealed to reduce the incidence of moderate to severe OHSS by this systematic review. However, the very limited number of participants and the quality of the included studies does not allow to recommend letrozole for the prevention of severe OHSS.
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Inhibidores de la Aromatasa , Fertilización In Vitro , Infertilidad Femenina , Síndrome de Hiperestimulación Ovárica , Inducción de la Ovulación , Femenino , Humanos , Embarazo , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/uso terapéutico , Fertilización In Vitro/métodos , Infertilidad Femenina/prevención & control , Infertilidad Femenina/etiología , Letrozol/uso terapéutico , Letrozol/administración & dosificación , Síndrome de Hiperestimulación Ovárica/prevención & control , Síndrome de Hiperestimulación Ovárica/epidemiología , Síndrome de Hiperestimulación Ovárica/etiología , Inducción de la Ovulación/métodos , Inducción de la Ovulación/efectos adversos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
OBJECTIVE: This study aimed to evaluate the oncological and reproductive outcomes of fertility-preserving re-treatment in progestin-resistant endometrial carcinoma (EC) and atypical endometrial hyperplasia (AEH) women who desire to maintain their fertility. METHODS: Our study included 61 progestin-resistant EC/AEH patients. These patients underwent treatment with gonadotropin-releasing hormone agonist (GnRHa) solely or a combination of GnRHa with levonorgestrel-releasing intrauterine system (LNG-IUD) or aromatase inhibitor (AI). Histological evaluations were performed every 3-4 months. Upon achieving complete remission (CR), we recommended maintenance treatments including LNG-IUD, cyclical oral contraceptives, or low-dose cyclic progestin until they began attempting conception. Regular follow-up was conducted for all patients. The chi-square method was utilized to compare oncological and fertility outcomes, while the Cox proportional hazards regression analysis helped identify risk factors for CR, recurrence, and pregnancy. RESULTS: Overall, 55 (90.2%) patients achieved CR, including 90.9% of AEH patients and 89.7% of EC patients. The median re-treatment time was 6 months (ranging from 3 to 12 months). The CR rate for GnRHa alone, GnRHa + LNG-IUD and GnRHa + AI were 80.0%, 91.7% and 93.3%, respectively. After a median follow-up period of 36 months (ranging from 3 to 96 months), 19 women (34.5%) experienced recurrence, 40.0% in AEH and 31.4% in EC patients, with the median recurrence time of 23 months (ranging from 6 to 77 months). Among the patients who achieved CR, 39 expressed a desire to conceive, 20 (51.3%) became pregnant, 11 (28.2%) had successfully deliveries, 1 (5.1%) was still pregnant, while 8 (20.5%) suffered miscarriages. CONCLUSION: GnRHa-based fertility-sparing treatment exhibited promising oncological and reproductive outcomes for progestin-resistant patients. Future larger multi-institutional studies are necessary to confirm these findings.
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Resistencia a Antineoplásicos , Hiperplasia Endometrial , Neoplasias Endometriales , Preservación de la Fertilidad , Progestinas , Humanos , Femenino , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/patología , Adulto , Estudios Retrospectivos , Preservación de la Fertilidad/métodos , Hiperplasia Endometrial/tratamiento farmacológico , Hiperplasia Endometrial/patología , Progestinas/administración & dosificación , Progestinas/uso terapéutico , Estudios de Seguimiento , Embarazo , Resistencia a Antineoplásicos/efectos de los fármacos , Hormona Liberadora de Gonadotropina/agonistas , Levonorgestrel/administración & dosificación , Persona de Mediana Edad , Pronóstico , Dispositivos Intrauterinos Medicados , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Índice de Embarazo , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Antineoplásicos Hormonales/uso terapéutico , Antineoplásicos Hormonales/administración & dosificaciónRESUMEN
OBJECTIVE: To evaluate the efficacy of two different regimens of Letrozole, an aromatase inhibitor, in the management of ectopic pregnancy compared to methotrexate. STUDY DESIGN: This randomized controlled trial was conducted on 88 women diagnosed with ectopic pregnancy with a baseline level of serum beta-human chorionic gonadotropin under 3000 mIU/mL between June 30, 2023, and December 30, 2023, at the Department of Obstetrics and Gynecology of the Vali-e-Asr Hospital affiliated with Tehran University of Medical Sciences. Participants were allocated into either methotrexate (n = 43), 5-day course Letrozole (n = 24), or 10-day course Letrozole (n = 21) treatments. The methotrexate group received a single dose of 50 mg/m2 dosage intramuscular methotrexate. The 5-day Letrozole group received a 2.5 mg Letrozole tablet three times daily for 5 days, whereas the 10-day Letrozole group received a 2.5 mg Letrozole tablet twice daily for 10 days. The primary outcome was the treatment response, defined as the achievement of a negative serum beta-human chorionic level without the need for additional methotrexate treatment or surgery. The secondary outcomes were the need for additional methotrexate dose or laparoscopic surgery intervention. The trial protocol was prospectively registered in ClinicalTrials.gov with code NCT05918718. RESULTS: The treatment response rates in methotrexate, 5-day Letrozole, and 10-day Letrozole groups were 76.7 %, 75.0 %, and 90.5 %, respectively, with no significant differences between the groups (P-value = 0.358). A total of 10 (23.3 %) patients from the methotrexate group, 3 (12.5 %) from the 5-day Letrozole group, and 2 (9.5 %) from the 10-day Letrozole group required an additional methotrexate dose, with no significant differences between the groups (P-value = 0.307). Furthermore, only 3 (12.5 %) patients, all from the 5-day Letrozole group, were suspected of tubal rupture and underwent surgery (P-value = 0.016). CONCLUSION: Our findings suggest Letrozole as a safe alternative to methotrexate in treating stable ectopic pregnancies, with a favorable treatment response rate. However, there is still a need for future larger studies to determine the applicability of Letrozole in the EP management. Also, the non-significant higher effectiveness of the 10-day Letrozole regimen than the 5-day Letrozole group underscores the need for future research to determine the optimal Letrozole regimen for the management of ectopic pregnancy.
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Abortivos no Esteroideos , Inhibidores de la Aromatasa , Letrozol , Metotrexato , Embarazo Ectópico , Humanos , Letrozol/uso terapéutico , Letrozol/administración & dosificación , Metotrexato/uso terapéutico , Metotrexato/administración & dosificación , Femenino , Embarazo , Embarazo Ectópico/tratamiento farmacológico , Embarazo Ectópico/sangre , Adulto , Abortivos no Esteroideos/uso terapéutico , Abortivos no Esteroideos/administración & dosificación , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Resultado del Tratamiento , Adulto JovenRESUMEN
PURPOSE: Everolimus in combination with endocrine therapy (ET) was formerly approved as 2nd-line therapy in HR(+)/HER2(-) advanced breast cancer (aBC) patients (pts) progressing during or after a non-steroidal aromatase inhibitor (NSAI). Since this approval, the treatment landscape of aBC has changed dramatically, particularly with the arrival of CDK 4-6 inhibitors. Endocrine monotherapy after progression to CDK4/6 inhibitors has shown a limited progression-free survival (PFS), below 3 months. Evidence of the efficacy of everolimus plus ET after CDK4/6 inhibitors is scarce. METHODS: A retrospective observational study of patients with aBC treated with everolimus and ET beyond CDK4/6-i progression compiled from February 2015 to December 2022 in 4 Spanish hospitals was performed. Clinical and demographic data were collected from medical records. The main objective was to estimate the median progression-free survival (mPFS). Everolimus adverse events (AE) were registered. Quantitative variables were summarized with medians; qualitative variables with proportions and the Kaplan-Meier method were used for survival estimates. RESULTS: One hundred sixty-one patients received everolimus plus ET (exemestane: 96, fulvestrant: 54, tamoxifen: 10, unknown: 1) after progressing on a CDK4/6 inhibitor. The median follow-up time was 15 months (interquartile range: 1-56 months). The median age at diagnosis was 49 years (range: 35-90 years). The estimated mPFS was 6.0 months (95%CI 5.3-7.8 months). PFS was longer in patients with previous CDK4/6 inhibitor therapy lasting for > 18 months (8.7 months, 95%CI 6.6-11.3 months), in patients w/o visceral metastases (8.0 months, 95%CI 5.8-10.5 months), and chemotherapy-naïve in the metastatic setting (7.2 months, 95%CI 5.9-8.4 months). CONCLUSION: This retrospective analysis cohort of everolimus plus ET in mBC patients previously treated with a CDK4/6 inhibitor suggests a longer estimated mPFS when compared with the mPFS with ET monotherapy obtained from current randomized clinical data. Everolimus plus ET may be considered as a valid control arm in novel clinical trial designs.
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Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Everolimus , Receptor ErbB-2 , Humanos , Everolimus/administración & dosificación , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/metabolismo , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Adulto , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Anciano de 80 o más Años , Receptores de Progesterona/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Tamoxifeno/uso terapéutico , Tamoxifeno/administración & dosificación , Antineoplásicos Hormonales/uso terapéutico , Antineoplásicos Hormonales/administración & dosificación , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Fulvestrant/administración & dosificación , Fulvestrant/uso terapéutico , Supervivencia sin Progresión , Androstadienos/administración & dosificación , Androstadienos/uso terapéutico , Progresión de la EnfermedadRESUMEN
PURPOSE: We previously reported that postmenopausal women with estrogen receptor-α-positive breast cancer receiving adjuvant anastrozole 1 mg/day (ANA1) with estrone (E1) ≥1.3 pg/mL and estradiol (E2) ≥0.5 pg/mL [inadequate estrogen suppression (IES)] had a threefold increased risk of a breast cancer event. The objective of this study was to determine if increasing anastrozole to 10 mg/day (ANA10) could result in adequate estrogen suppression (AES: E1 <1.3 pg/mL and/or E2 <0.5 pg/mL) among those with IES on ANA1. PATIENTS AND METHODS: Postmenopausal women with estrogen receptor-α-positive breast cancer planning to receive adjuvant ANA1 were eligible. E1 and E2 were assessed pre- and post-8 to 10 weeks of ANA1. Those with IES were switched to 8- to 10-week cycles of ANA10 followed by letrozole 2.5 mg/day. E1 and E2 were assessed after each cycle. Anastrozole concentrations were measured post-ANA1 and post-ANA10. Primary analyses included patients who documented taking at least 80% of the planned treatment (adherent cohort). RESULTS: In total, 132 (84.6%) of 156 eligible patients were ANA1 adherent. IES occurred in 40 (30.3%) adherent patients. Twenty-five (78.1%) of 32 patients who began ANA10 were adherent, and AES was achieved in 19 (76.0%; 90% confidence interval, 58.1%-89.0%) patients. Anastrozole concentrations post-ANA1 and post-ANA10 did not differ by estrogen suppression status among adherent patients. AES was maintained/attained in 21 (91.3%) of 23 letrozole-adherent patients. CONCLUSIONS: Approximately 30% of ANA1-adherent patients had IES. Among those who switched to ANA10 and were adherent, 76% had AES. Further studies are required to validate emerging data that ANA1 results in IES for some patients and to determine the clinical benefit of switching to ANA10 or an alternative aromatase inhibitor.
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Anastrozol , Neoplasias de la Mama , Nitrilos , Posmenopausia , Triazoles , Humanos , Anastrozol/administración & dosificación , Anastrozol/uso terapéutico , Anastrozol/efectos adversos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Persona de Mediana Edad , Anciano , Triazoles/administración & dosificación , Triazoles/efectos adversos , Nitrilos/administración & dosificación , Nitrilos/efectos adversos , Estrógenos/administración & dosificación , Estadificación de Neoplasias , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/uso terapéutico , Estudios Prospectivos , Estradiol/administración & dosificación , Estrona/sangre , Estrona/administración & dosificación , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/efectos adversosRESUMEN
BACKGROUND: Letrozole, an aromatase inhibitor metabolised via CYP2A6 and CYP3A4/5 enzymes, is used as adjuvant therapy for women with hormone receptor (HR)-positive early breast cancer. The objective of this study was to quantify the impact of CYP2A6 genotype on letrozole pharmacokinetics (PK), to identify non-adherent patients using a population approach and explore the possibility of a relationship between non-adherence and early relapse. METHODS: Breast cancer patients enrolled in the prospective PHACS study (ClinicalTrials.gov NCT01127295) and treated with adjuvant letrozole 2.5 mg/day were included. Trough letrozole concentrations (Css,trough) were measured every 6 months for 3 years by a validated LC-MS/MS method. Concentration-time data were analysed using non-linear mixed effects modelling. Three methods were evaluated for identification of non-adherent subjects using the base PK model. RESULTS: 617 patients contributing 2534 plasma concentrations were included and led to a one-compartment PK model with linear absorption and elimination. Model-based methods identified 28 % of patients as non-adherent based on high fluctuations of their Css,trough compared to 3 % based on patient declarations. The covariate analysis performed in adherent subjects revealed that CYP2A6 intermediate (IM) and slow metabolisers (SM) had 21 % (CI95 % = 12 - 30 %) and 46 % (CI95 % = 41 - 51 %) lower apparent clearance, respectively, compared to normal and ultrarapid metabolisers (NM+UM). Early relapse (19 patients) was not associated with model-estimated, concentration-based or declared adherence in the total population (p = 0.41, p = 0.37 and p = 0.45, respectively). CONCLUSIONS: These findings will help future investigations focusing on the exposure-efficacy relationship for letrozole in adjuvant setting.
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Inhibidores de la Aromatasa , Neoplasias de la Mama , Letrozol , Cumplimiento de la Medicación , Humanos , Letrozol/farmacocinética , Letrozol/administración & dosificación , Letrozol/uso terapéutico , Letrozol/sangre , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Persona de Mediana Edad , Anciano , Inhibidores de la Aromatasa/farmacocinética , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/sangre , Adulto , Quimioterapia Adyuvante/métodos , Modelos Biológicos , Estudios Prospectivos , Receptores de Estrógenos/metabolismo , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Antineoplásicos/sangre , Antineoplásicos/administración & dosificación , Anciano de 80 o más AñosRESUMEN
BACKGROUND: In MONARCH 2, the addition of abemaciclib to fulvestrant significantly improved both progression-free survival (PFS) and overall survival (OS) in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) with disease progression on prior endocrine therapy. In MONARCH 3, the addition of abemaciclib to a nonsteroidal aromatase inhibitor (NSAI) as initial therapy for HR+, HER2- ABC significantly improved PFS. Here, we present the prespecified final OS results for MONARCH 3. PATIENTS AND METHODS: MONARCH 3 is a randomized, double-blind, phase III study of abemaciclib plus NSAI (anastrozole or letrozole) versus placebo plus NSAI in postmenopausal women with HR+, HER2- ABC without prior systemic therapy in the advanced setting. The primary objective was investigator-assessed PFS; OS was a gated secondary endpoint, and chemotherapy-free survival was an exploratory endpoint. RESULTS: A total of 493 women were randomized 2 : 1 to receive abemaciclib plus NSAI (n = 328) or placebo plus NSAI (n = 165). After a median follow-up of 8.1 years, there were 198 OS events (60.4%) in the abemaciclib arm and 116 (70.3%) in the placebo arm (hazard ratio, 0.804; 95% confidence interval 0.637-1.015; P = 0.0664, non-significant). Median OS was 66.8 versus 53.7 months for abemaciclib versus placebo. In the subgroup with visceral disease, there were 113 OS events (65.3%) in the abemaciclib arm and 65 (72.2%) in the placebo arm (hazard ratio, 0.758; 95% confidence interval 0.558-1.030; P = 0.0757, non-significant). Median OS was 63.7 months versus 48.8 months for abemaciclib versus placebo. The previously demonstrated PFS benefit was sustained, and chemotherapy-free survival numerically improved with the addition of abemaciclib. No new safety signals were observed. CONCLUSIONS: Abemaciclib combined with an NSAI resulted in clinically meaningful improvement in median OS (intent-to-treat population: 13.1 months; subgroup with visceral disease: 14.9 months) in patients with HR+ HER2- ABC; however, statistical significance was not reached.
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Aminopiridinas , Protocolos de Quimioterapia Combinada Antineoplásica , Inhibidores de la Aromatasa , Bencimidazoles , Neoplasias de la Mama , Letrozol , Receptor ErbB-2 , Receptores de Estrógenos , Receptores de Progesterona , Humanos , Femenino , Aminopiridinas/administración & dosificación , Aminopiridinas/uso terapéutico , Bencimidazoles/administración & dosificación , Bencimidazoles/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inhibidores , Método Doble Ciego , Letrozol/administración & dosificación , Letrozol/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Persona de Mediana Edad , Anciano , Receptores de Progesterona/metabolismo , Receptores de Estrógenos/metabolismo , Anastrozol/uso terapéutico , Anastrozol/administración & dosificación , Adulto , Anciano de 80 o más Años , Supervivencia sin ProgresiónRESUMEN
PURPOSE: Although changes in circulating tumour DNA (ctDNA) in breast cancer are well described, the kinetics of their fluctuations has not been described over short timescales. We investigated ctDNA dynamics during alternating cycles of chemotherapy and hormonal treatment in pre-treated patients with oestrogen receptor-positive metastatic breast cancer. METHODS: Patients received alternating, 9-week cycles of eribulin and aromatase inhibitors (AIs). The clinical primary endpoint, progression-free survival (PFS), was monitored at 3, 6 and 9 months; secondary endpoints, clinical benefit rate (CBR), safety and tolerability profiles, were also assessed. Importantly, ctDNA fluctuations were monitored using the Oncomine™ Breast cfDNA assay to test whether biomarkers may change rapidly between chemotherapy and aromatase inhibitor (AI) treatment in the setting of advanced breast cancer, potentially reflecting disease dynamics. RESULTS: The median PFS was 202 days (95% CI: 135-undefined) and 235 days (95% CI: 235-undefined) at 6 and 9 months, respectively, with a 50% CBR at both 6 and 9 months. Dynamic changes in ctDNA were observed in short timescales between chemotherapy and AI treatment and support the clinical benefit (CB) seen in individual patients and, critically, appear informative of acquired resistance in real time. CONCLUSION: Changes in ctDNA can occur rapidly and reflect changes in patients' clinical tumour responses (NCT02681523).
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Protocolos de Quimioterapia Combinada Antineoplásica , Inhibidores de la Aromatasa , Neoplasias de la Mama , ADN Tumoral Circulante , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Biomarcadores de Tumor/sangre , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/sangre , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/genética , ADN Tumoral Circulante/sangre , ADN Tumoral Circulante/genética , Furanos/uso terapéutico , Furanos/administración & dosificación , Cetonas , Metástasis de la Neoplasia , Policétidos Poliéteres , Resultado del TratamientoRESUMEN
INTRODUCTION: Low vitamin D status is prevalent among women with polycystic ovary syndrome (PCOS). The objective of the study is to assess the effect of vitamin D supplementation on (1) the ovulation rate to letrozole and (2) other reproductive, endocrine and metabolic outcomes after 1 year of supplementation in women with PCOS. METHODS AND ANALYSIS: This is a multicentre, randomised, double-blind, controlled clinical trial. A total of 220 anovulatory women with PCOS diagnosed by the Rotterdam criteria will be recruited. They will be randomly assigned to either the (1) vitamin D supplementation group or (2) placebo group. Those in the vitamin D group will take oral Vitamin D3 50 000 IU/week for 4 weeks, followed by 50 000 IU once every 2 weeks for 52 weeks. Those who remain anovulatory after 6 months will be treated with a 6-month course of letrozole (2.5 mg to 7.5 mg for 5 days per cycle titrated according to response) for ovulation induction. The primary outcome is the ovulation rate. All statistical analyses will be performed using intention-to-treat and per protocol analyses. ETHICS AND DISSEMINATION: Ethics approval was sought from the Institutional Review Board of the participating units. All participants will provide written informed consent before joining the study. The results of the study will be submitted to scientific conferences and peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04650880.
Asunto(s)
Letrozol , Inducción de la Ovulación , Ovulación , Síndrome del Ovario Poliquístico , Adulto , Femenino , Humanos , Adulto Joven , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Suplementos Dietéticos , Método Doble Ciego , Letrozol/uso terapéutico , Letrozol/administración & dosificación , Estudios Multicéntricos como Asunto , Ovulación/efectos de los fármacos , Inducción de la Ovulación/métodos , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/complicaciones , Ensayos Clínicos Controlados Aleatorios como Asunto , Vitamina D/uso terapéutico , Vitamina D/administración & dosificaciónRESUMEN
INTRODUCTION: Estrogen receptor positive (ER+) breast cancer is the most common breast cancer subtype, and therapeutic management relies primarily on inhibiting ER signaling. In the metastatic setting, ER signaling is typically targeted by selective estrogen receptor degraders (SERDs) or aromatase inhibitors (AIs), the latter of which prevent estrogen production. Activating ESR1 mutations are among the most common emergent breast cancer mutations and confer resistance to AIs. AREAS COVERED: Until 2023, fulvestrant was the only approved SERD; fulvestrant is administered intramuscularly, and in some cases may also have limited efficacy in the setting of certain ESR1 mutations. In 2023, the first oral SERD, elacestrant, was approved for use in ESR1-mutated, ER+/HER2- advanced breast cancer and represents a new class of therapeutic options. While the initial approval was as monotherapy, ongoing studies are evaluating elacestrant (as well as other oral SERDs) in combination with other therapies including CDK4/6 inhibitors and PI3K inhibitors, which parallels the current combination uses of fulvestrant. EXPERT OPINION: Elacestrant's recent approval sheds light on the use of biomarkers such as ESR1 to gauge a tumor's endocrine sensitivity. Ongoing therapeutic and correlative biomarker studies will offer new insight and expanding treatment options for patients with advanced breast cancer.
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Neoplasias de la Mama , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Femenino , Administración Oral , Inhibidores de la Aromatasa/farmacología , Inhibidores de la Aromatasa/administración & dosificación , Receptor alfa de Estrógeno/metabolismo , Receptor alfa de Estrógeno/genética , Animales , Mutación , Fulvestrant/administración & dosificación , Fulvestrant/farmacología , Resistencia a Antineoplásicos , Receptores de Estrógenos/metabolismo , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Moduladores Selectivos de los Receptores de Estrógeno/administración & dosificación , Terapia Molecular Dirigida , Transducción de Señal/efectos de los fármacosRESUMEN
BACKGROUND: Ribociclib has been shown to have a significant overall survival benefit in patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Whether this benefit in advanced breast cancer extends to early breast cancer is unclear. METHODS: In this international, open-label, randomized, phase 3 trial, we randomly assigned patients with HR-positive, HER2-negative early breast cancer in a 1:1 ratio to receive ribociclib (at a dose of 400 mg per day for 3 weeks, followed by 1 week off, for 3 years) plus a nonsteroidal aromatase inhibitor (NSAI; letrozole at a dose of 2.5 mg per day or anastrozole at a dose of 1 mg per day for ≥5 years) or an NSAI alone. Premenopausal women and men also received goserelin every 28 days. Eligible patients had anatomical stage II or III breast cancer. Here we report the results of a prespecified interim analysis of invasive disease-free survival, the primary end point; other efficacy and safety results are also reported. Invasive disease-free survival was evaluated with the use of the Kaplan-Meier method. The statistical comparison was made with the use of a stratified log-rank test, with a protocol-specified stopping boundary of a one-sided P-value threshold of 0.0128 for superior efficacy. RESULTS: As of the data-cutoff date for this prespecified interim analysis (January 11, 2023), a total of 426 patients had had invasive disease, recurrence, or death. A significant invasive disease-free survival benefit was seen with ribociclib plus an NSAI as compared with an NSAI alone. At 3 years, invasive disease-free survival was 90.4% with ribociclib plus an NSAI and 87.1% with an NSAI alone (hazard ratio for invasive disease, recurrence, or death, 0.75; 95% confidence interval, 0.62 to 0.91; P = 0.003). Secondary end points - distant disease-free survival and recurrence-free survival - also favored ribociclib plus an NSAI. The 3-year regimen of ribociclib at a 400-mg starting dose plus an NSAI was not associated with any new safety signals. CONCLUSIONS: Ribociclib plus an NSAI significantly improved invasive disease-free survival among patients with HR-positive, HER2-negative stage II or III early breast cancer. (Funded by Novartis; NATALEE ClinicalTrials.gov number, NCT03701334.).
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Protocolos de Quimioterapia Combinada Antineoplásica , Inhibidores de la Aromatasa , Neoplasias de la Mama , Letrozol , Femenino , Humanos , Aminopiridinas/administración & dosificación , Aminopiridinas/efectos adversos , Aminopiridinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Letrozol/administración & dosificación , Letrozol/efectos adversos , Letrozol/uso terapéutico , Purinas/administración & dosificación , Purinas/efectos adversos , Purinas/uso terapéutico , Receptor ErbB-2/metabolismo , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/efectos adversos , Inhibidores de la Aromatasa/uso terapéutico , Receptores de Estrógenos , Receptores de Progesterona , Goserelina/administración & dosificación , Goserelina/efectos adversos , Goserelina/uso terapéutico , Antineoplásicos Hormonales , MasculinoRESUMEN
WHAT IS THIS SUMMARY ABOUT?: This summary describes an article published in the medical journal Frontiers in Oncology in September 2023. The article reports results from a study that looked at breast cancer treatments for older patients aged 75 years or older. The study focused on a type of cancer called HR+/HER2- metastatic breast cancer. HR+/HER2- stands for hormone receptorpositive/human epidermal growth factor receptor 2-negative. This study evaluated whether older patients with this type of cancer benefited from the combination of two medicines - palbociclib and an aromatase inhibitor - compared with taking an aromatase inhibitor alone. HOW WAS THE STUDY IN THIS SUMMARY CARRIED OUT?: The Flatiron database contains medical records for people with cancer in the US. This study used deidentified health care information from this database. 'Deidentified' means that all information that could identify an individual was removed to protect individuals' privacy. People in this study received treatment in routine care and not in a clinical trial. WHAT DO THE RESULTS MEAN?: Older patients who took palbociclib plus an aromatase inhibitor lived longer than those who took an aromatase inhibitor alone. Older patients who took palbociclib plus an aromatase inhibitor also lived longer without their cancer getting worse and started chemotherapy later than those who took an aromatase inhibitor alone. These results support using palbociclib plus an aromatase inhibitor as the first treatment for patients aged 75 years or older with HR+/HER2- metastatic breast cancer.
This study evaluated outcomes in elderly patients with metastatic breast cancer treated in routine care. Overall, patients who took palbociclib plus an aromatase inhibitor (AI) lived longer, and lived longer without their cancer getting worse, than those who took an AI alone.
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Protocolos de Quimioterapia Combinada Antineoplásica , Inhibidores de la Aromatasa , Neoplasias de la Mama , Piperazinas , Piridinas , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Femenino , Inhibidores de la Aromatasa/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Piridinas/uso terapéutico , Piridinas/administración & dosificación , Anciano , Piperazinas/uso terapéutico , Piperazinas/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anciano de 80 o más Años , Resultado del Tratamiento , Metástasis de la Neoplasia , Receptor ErbB-2/metabolismoRESUMEN
AIM: To investigate the impact of letrozole cotreatment progestin-primed ovarian stimulation (PPOS) (Le PPOS) in controlled ovarian stimulation (COS) and the pregnancy outcomes in frozen-thawed embryo transfer cycles. METHODS: This retrospective cohort study included women who underwent in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). A total of 2575 cycles were included (1675 in the Le PPOS group and 900 in the PPOS group). The primary outcome was the clinical pregnancy rates. The secondary outcome was the live birth rates. RESULTS: In this study, propensity score matching (PSM) was performed to create a perfect match of 379 patients in each group. After matching, the numbers of oocytes retrieved, mature oocytes, fertilization, and clinical pregnancy rates were more favorable in the Le PPOS group than in the PPOS group (all p < 0.05). The multivariable analysis showed that the clinical pregnancy rate was higher in the Le PPOS than in the PPOS group (odds ratio = 1.46, 95% confidence interval: 1.05-2.04, p = 0.024) after adjusting for potentially confounding factors (age, anti-Müllerian hormone levels, antral follicular count, the type of embryo transferred, number of transferred embryos, body mass index, and follicular stimulating hormone and estradiol levels on starting day). CONCLUSIONS: This retrospective study with a limited sample size suggests that the Le PPOS protocol might be an alternative to the PPOS protocol in women undergoing COS and could lead to better pregnancy outcomes. The results should be confirmed using a formal randomized controlled trial.
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Fertilización In Vitro , Letrozol , Inducción de la Ovulación , Índice de Embarazo , Progestinas , Humanos , Femenino , Letrozol/administración & dosificación , Letrozol/farmacología , Inducción de la Ovulación/métodos , Embarazo , Adulto , Estudios Retrospectivos , Fertilización In Vitro/métodos , Progestinas/administración & dosificación , Progestinas/farmacología , Inyecciones de Esperma Intracitoplasmáticas/métodos , Transferencia de Embrión/métodos , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/farmacologíaRESUMEN
PURPOSE: Aromatase inhibitor (AI) therapy reduces risk of recurrence and death for postmenopausal women with breast cancer (BC); however, AI-induced arthralgia (AIIA) can lead to discontinuation of treatment. Curcumin, a bioactive polyphenolic substance, may help ameliorate inflammation-related conditions including osteoarthritis and pain. METHODS: We conducted a multisite randomized placebo-controlled, double-blind pilot trial (Alliance A22_Pilot9) to evaluate the effects of nanoemulsion curcumin (NEC, 200 mg/day) in postmenopausal women experiencing AIIA for ≥ 3 months. The primary objective was to determine the feasibility of using Functional Assessment of Cancer Treatment-Endocrine Symptoms (FACT-ES) to detect changes from 0 (T0) to 3 months (T3) of NEC treatment in AI-induced symptoms and well-being; secondary objectives included evaluation of changes in Disabilities of the Shoulder, Arm, and Hand (DASH), Brief Pain Inventory-short form (BPI-SF), grip strength, and biomarkers at T0 and T3. RESULTS: Forty-two patients were randomized to NEC or placebo; 34 women completed the 3-month study. Patient-reported outcome measures (PROMs: FACT-ES, DASH, BPI-SF) and biospecimens were collected at T0-T3 in > 80% of participants. Adherence was ≥ 90% for both arms. PROMs and grip strength did not differ significantly by treatment arm. Plasma curcumin was detected only in NEC arm participants. Serum estradiol and estrone levels were below detection or low on study agent. Gastrointestinal adverse effects were commonly reported in both arms. CONCLUSION: NEC versus placebo in a multisite randomized trial is feasible and well-tolerated. Additional studies with larger sample size are needed to further evaluate the efficacy and safety of NEC in treatment of AIIA. CLINICALTRIALS: gov Identifier: NCT03865992, first posted March 7, 2019.
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Inhibidores de la Aromatasa , Neoplasias de la Mama , Curcumina , Humanos , Femenino , Curcumina/uso terapéutico , Curcumina/administración & dosificación , Inhibidores de la Aromatasa/efectos adversos , Inhibidores de la Aromatasa/administración & dosificación , Proyectos Piloto , Persona de Mediana Edad , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Método Doble Ciego , Emulsiones , Resultado del Tratamiento , Posmenopausia , Artralgia/inducido químicamente , Artralgia/tratamiento farmacológicoRESUMEN
The benign prostatic hyperplasia (BPH) is the main source of lower urinary tract symptoms. The BPH is a common age-dependent disease and tamsulosin is an α1-adrenoceptor blocker widely prescribed for BPH. Beyond the common adverse effects of tamsulosin, increased diagnosis of dementia after prescription was observed. Importantly, a clinical study suggested that tamsulosin may exert antidepressant effects in BPH patients. Considering the expression of α1-adrenoceptors in the brain, this study aimed to investigate the effects of tamsulosin in the forced swimming and open field tests in mice. For this, tamsulosin (0.001-1 mg/kg) was orally administered subacutely (1, 5 and 23 hr) and acutely (60 min) before tests. Mifepristone (10 mg/kg), a glucocorticoid receptor antagonist, and aminoglutethimide (10 mg/kg), a streoidogenesis inhibitor, were intraperitoneally injected before tamsulosin to investigate the role of the hypothalamic-pituitary-adrenal axis in the mediation of tamsulosin-induced effects. Subacute and acute administrations of tamsulosin increased the immobility time in the first exposition to an inescapable stressful situation. In the re-exposition to the swim task, controls displayed a natural increase in the immobility time, and the treatment with tamsulosin further increased this behavioral parameter. Tamsuslosin did not affect spontaneous locomotion neither in naïve nor in stressed mice. Our findings also showed that mifepristone and aminoglutethimide prevented the tamsulosin-induced increase in the immobility time in the first and second swimming sessions, respectively. In conclusion, tamsulosin may contribute to increased susceptibility to depressive-like behaviors, by facilitating the acquisition of a passive stress-copying strategy. These effects seem to be dependent on endogenous glucocorticoids.
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Adaptación Psicológica/efectos de los fármacos , Antagonistas de Receptores Adrenérgicos alfa 1/farmacología , Inhibidores de la Aromatasa/farmacología , Depresión/inducido químicamente , Antagonistas de Hormonas/farmacología , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Receptores de Glucocorticoides/antagonistas & inhibidores , Tamsulosina/farmacología , Antagonistas de Receptores Adrenérgicos alfa 1/administración & dosificación , Aminoglutetimida/farmacología , Animales , Inhibidores de la Aromatasa/administración & dosificación , Conducta Animal/efectos de los fármacos , Modelos Animales de Enfermedad , Antagonistas de Hormonas/administración & dosificación , Ratones , Mifepristona/farmacología , Tamsulosina/administración & dosificaciónRESUMEN
ABSTRACT: Palbociclib has shown satisfactory outcomes when combined with endocrine therapy (ET) in hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2-) metastatic breast cancer (MBC). However, data in Asia are currently scarce.This retrospective study aimed to evaluate the real-world effectiveness, sensitivity, and toxicity of palbociclib plus ET in HR+/HER2- MBC in North China. We recruited patients with HR+/HER2- MBC from August 2018 to July 2020 across 7 hospitals in North China. The primary endpoint was to evaluate progression-free survival (PFS) after initial progress on palbociclib therapy. The secondary endpoints included determining predictive biomarkers of palbociclib sensitivity and toxicity of palbociclib.A total of 54 patients were analyzed in this cohort with an estimated median follow-up time of 14.3âmonths. Patients who received palbociclib as a first-line treatment showed significantly prolonged PFS compared with those who received palbociclib as a second-line or beyond treatment (21.8âmonths vs 15.9âmonths vs 6.8âmonths) (Pâ<â.001). Besides, patients with Ki67 <30% (Pâ=â.024) and PR ≥20% (Pâ=â.041) in metastatic tumors had significantly longer PFS. The Cox proportional-hazards regression analyses proved that different lines (Pâ=â.001 in multivariate analysis), Ki67 <30% (Pâ=â.035 in multivariate analysis), and PR ≥20% (Pâ=â.045 in univariate analysis) in metastatic tumors affected PFS significantly. The most common adverse events were hematologic, with 31.48% of patients having neutropenia.Palbociclib plus ET significantly prolonged PFS for patients with HR+/HER2- MBC who received first-line therapy, with manageable toxicity. The values of Ki67 and PR in metastatic tumors may be potential predictive biomarkers of palbociclib sensitivity.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Piperazinas/uso terapéutico , Piridinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Inhibidores de la Aromatasa/administración & dosificación , Quinasa 4 Dependiente de la Ciclina , Femenino , Humanos , Antígeno Ki-67 , Metástasis de la Neoplasia , Piperazinas/efectos adversos , Inhibidores de Proteínas Quinasas/administración & dosificación , Piridinas/efectos adversos , Receptores de Estrógenos/metabolismo , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Objective: To evaluate the clinical effect of mild stimulation with letrozole on pregnancy outcomes in ovulatory women undergoing frozen embryo transfer (FET) compared to natural cycle. Design: Retrospective observational study. Setting: Tertiary care academic medical center. Population: A total of 6,874 infertile women with regular menstrual cycles (21-35 days) met the criteria for this study in the period from 2013 to 2020. Methods: All patients who were prepared for and underwent FET were divided into two groups: a modified natural cycle (NC) group (n=3,958) and a letrozole cycle group (n=2,916). Main Outcome Measures: The primary outcome of the study was clinical pregnancy rate. Secondary outcome measures were endometrial thickness, rates of implantation, positive HCG test, live birth, early miscarriage and ectopic pregnancy. Results: The clinical pregnancy rate was not statistically different between the modified NC-FET group and the letrozole-FFT group before (crude OR 0.99, 95% CI 0.90-1.09, P=0.902>0.05) and after propensity score matching (PSM) (crude OR 1.01, 95% CI 0.91-1.12, P=0.870>0.05). After multivariable logistic regression analysis, the clinical pregnancy rate remained insignificant before (adjusted OR 1.00, 95% CI 0.91-1.10, P=0.979>0.05) and after matching (adjusted OR 1.00, 95% CI 0.89-1.11, P=0.936>0.05), respectively. Similarly, in the crude and adjusted analysis, the positive HCG test, implantation, live birth and early miscarriage rates were also comparable in the letrozole-FFT group and modified NC-FET group before and after matching. Furthermore, the endometrial thickness of letrozole-FFT group was similar to that of modified NC-FET group with adjusted analysis. Conclusion: Our observation suggests that mild stimulation with letrozole could produce similar pregnancy outcomes in ovulatory patients who undergo FET when compared with a natural cycle.