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PURPOSE: To evaluate the prognostic value of peripheral lymphocyte count (PLC) in the breast cancer patients after breast-conserving surgery (BCS) with radiotherapy (RT). METHODS AND MATERIALS: This post hoc analysis was performed using data of 628 patients from a phase III, randomized controlled trial comparing hypofractionated RT (HFRT) with conventional fractionated RT (CFRT) after BCS. PLCs were obtained before, during, and after RT until the 1-year follow-up. The optimal cut-off PLCs were determined using the maxstat package in R. Survival rates were estimated using the Kaplan-Meier method and compared with the log-rank test. RESULTS: A total of 275 (46.1 %) patients developed lymphopenia during RT, among them, 17 (2.8 %) had grade 3 lymphopenia and no one developed grade 4 lymphopenia. With a median follow-up of 110.8 months, patients with pre-RT PLCs of < 1.77 × 109/L had a significantly lower 10-year breast cancer-specific survival (BCSS) rate (P = 0.013) and overall survival (OS) rate (P = 0.026). Patients with a nadir PLC of < 1.35 × 109/L had a significantly poorer 10-year OS rate (P = 0.048). Multivariate analysis showed that a pre-RT PLC of < 1.77 × 109/L was an independent factor influencing BCSS and OS, while the effect of the nadir PLC did not remain significant. Neither PLC nor lymphopenia recovery at post-RT 1, 3, and 6 months and 1 year was associated with survival. CONCLUSIONS: Radiation-induced lymphopenia in patients with breast cancer after BCS tends to be mild. The lower pre-RT PLC predicted poorer survival.
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This study was to report proxy measures for mortality risk in patients with hematological malignancies across 185 countries globally and explore its association with their socioeconomic status and treatment. The incidence, mortality, and 5-year prevalence data were extracted from the GLOBOCAN database. The data regarding the human development index (HDI), gross national income (GNI), vulnerability index, and concordance with cancer Essential Medicines List (EML) were obtained from open-source reports. The ratio of mortality to 5-year-prevalence (MPR) and that of mortality to incidence (MIR) were calculated and age-standardized using Segi's world standard population. Finally, the possible associations were assessed using Pearson correlation analyses. In 2020, the global incidence, mortality, and 5-year prevalence of HMs were 1,278,362, 711,840, and 3,616,685, respectively. Global age-standardized MPR and MIR were 0.15 and 0.44, respectively; they varied significantly among 6 regions, 185 countries, 4 HM types, and 4 HDI groups worldwide. Older populations always had higher ratios. The correlation of MPRs and MIRs with HDI, GNI, and concordance with cancer EML was negative, whereas it was positive with the vulnerability index (lower was better). Increasing access to cancer drugs in resource-limited regions with a focus on vulnerable children may aid in reducing HM-related mortality risk.
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Salud Global , Neoplasias Hematológicas , Humanos , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/epidemiología , Incidencia , Prevalencia , Femenino , Masculino , Factores de Riesgo , Disparidades en Atención de Salud , Análisis de DatosRESUMEN
Recently, progression-free survival at 24 months (PFS24) was defined as clinically relevant for patients with extranodal NK/T cell lymphoma. Herein, the clinical data from two independent random cohorts (696 patients each in the primary and validation datasets) were used to develop and validate a risk index for PFS24 (PFS24-RI), and evaluate its ability to predict early progression. Patients achieving PFS24 had a 5-year overall survival (OS) of 95.8%, whereas OS was only 21.2% in those failing PFS24 (P<0.001). PFS24 was an important predictor of subsequent OS, independent of risk stratification. The proportion of patients achieving PFS24 and 5-year OS rates correlated linearly among risk-stratified groups. Based on multivariate analysis of the primary dataset, the PFS24-RI included five risk factors: stage II or III/IV, elevated lactate dehydrogenase, Eastern Cooperative Oncology Group score ≥2, primary tumor invasion, and extra-upper aerodigestive tract. PFS24-RI stratified the patients into low-risk (0), intermediate-risk (1-2), high-risk (≥3) groups with different prognoses. Harrell's C-index of PFS24-RI for PFS24 prediction was 0.667 in the validation dataset, indicating a good discriminative ability. PFS24-RI calibration indicated that the actual observed and predicted probability of failing PFS24 agreed well. PFS24-RI provided the probability of achieving PFS24 at an individual patient level.
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Linfoma Extranodal de Células NK-T , Humanos , Estadificación de Neoplasias , Pronóstico , Supervivencia sin Progresión , Células Asesinas Naturales/patología , Estudios RetrospectivosRESUMEN
Objectives: To investigate the dosimetric advantages of the voluntary deep inspiration breath-hold technique assisted by optical surface monitoring system for whole breast irradiation in left breast cancer after breast-conserving surgery and verify the reproducibility and acceptability of this technique. Methods: Twenty patients with left breast cancer receiving whole breast irradiation after breast-conserving surgery were enrolled in this prospective phase II study. Computed tomography simulation was performed during both free breathing and voluntary deep inspiration breath-hold for all patients. Whole breast irradiation plans were designed, and the volumes and doses of the heart, left anterior descending coronary artery, and lung were compared between free breathing and voluntary deep inspiration breath-hold. Cone beam computed tomography was performed for the first 3 treatments, then weekly during voluntary deep inspiration breath-hold treatment to evaluate the accuracy of the optical surface monitoring system technique. The acceptance of this technique was evaluated with in-house questionnaires completed by patients and radiotherapists. Results: The median age was 45 (27-63) years. All patients received hypofractionated whole breast irradiation using intensity-modulated radiation therapy up to a total dose of 43.5 Gy/2.9 Gy/15f. Seventeen of the 20 patients received concomitant tumor bed boost to a total dose of 49.5 Gy/3.3 Gy/15f. Voluntary deep inspiration breath-hold showed a significant decrease in the heart mean dose (262 ± 163 cGy vs 515 ± 216 cGy, P < .001) and left anterior descending coronary artery (1191 ± 827 cGy vs 1794 ± 833 cGy, P < .001). The median delivery time of radiotherapy was 4 (1.5-11) min. The median deep breathing cycles were 4 (2-9) times. The average score for acceptance of voluntary deep inspiration breath-hold by patients and radiotherapists was 8.7 ± 0.9 (out of 12) and 10.6 ± 3.2 (out of 15), respectively, indicating good acceptance by both. Conclusions: The voluntary deep inspiration breath-hold technique for whole breast irradiation after breast-conserving surgery in patients with left breast cancer significantly reduces the cardiopulmonary dose. Optical surface monitoring system-assisted voluntary deep inspiration breath-hold is reproducible and feasible and showed good acceptance by both patients and radiotherapists.
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Neoplasias de la Mama , Radioterapia de Intensidad Modulada , Neoplasias de Mama Unilaterales , Humanos , Persona de Mediana Edad , Femenino , Neoplasias de Mama Unilaterales/diagnóstico por imagen , Neoplasias de Mama Unilaterales/radioterapia , Neoplasias de Mama Unilaterales/cirugía , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Estudios Prospectivos , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Magnetic resonance imaging (MRI) performs well in the locoregional assessment of extranodal nasal-type NK/T-cell lymphoma (ENKTCL). It's important to assess the value of multi-modal MRI-based radiomics for estimating overall survival (OS) in patients with ENKTCL. METHODS: Patients with ENKTCL in a prospectively cohort were systemically reviewed and all the pretreatment MRI were acquisitioned. An unsupervised spectral clustering method was used to identify risk groups of patients and radiomic features. A nomogram-revised risk index (NRI) plus MRI radiomics signature (NRI-M) was developed, and compared with the NRI. RESULTS: The 2 distinct type I and II groups of the MRI radiomics signatures were identified. The 5-year OS rates between the type I and type II groups were 87.2% versus 67.3% (P = 0.002) in all patients, and 88.8% versus 69.2% (P = 0.003) in early-stage patients. The discrimination and calibration of the NRI-M for OS prediction demonstrated a better performance than that of either MRI radiomics or NRI, with a mean area under curve (AUC) of 0.748 and 0.717 for predicting the 5-year OS in all-stages and early-stage patients. CONCLUSIONS: The NRI-M model has good performance for predicting the prognosis of ENKTCL and may help design clinical trials and improve clinical decision making.
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Linfoma Extranodal de Células NK-T , Linfoma de Células T , Humanos , Pronóstico , Imagen por Resonancia Magnética/métodos , Nomogramas , Medición de Riesgo , Estudios Retrospectivos , Linfoma Extranodal de Células NK-T/diagnóstico por imagen , Linfoma Extranodal de Células NK-T/patologíaRESUMEN
PURPOSE: To investigate the appropriate timing of radiotherapy (RT) after mastectomy and adjuvant chemotherapy for women with high-risk breast cancer. PATIENTS AND METHODS: Post hoc analyses of 584 patients with stage II and III breast cancer from a randomised controlled clinical trial were performed. All patients underwent mastectomy followed by sequential chemotherapy and RT. The optimal cut-off values for the surgery-RT interval (SRI) and the chemotherapy-RT interval (CRI) for overall survival (OS) were determined using the hazard ratio for continuous predictors. The locoregional recurrence (LRR), distant metastasis (DM), disease-free survival (DFS), and OS rates were estimated using the Kaplan-Meier method. Multivariate analyses were performed using Cox proportional hazards regression. RESULTS: Median follow-up time was 83.5 months. Median SRI and CRI were 168 and 27 days, respectively. An SRI of >210 days was independently associated with higher DM (HR 2.65, 95% CI: 1.49-4.71; HR 2.78, 95% CI 1.51-5.26), lower OS (HR 2.44, 95% CI: 1.28-4.54; HR 2.50, 95% CI: 1.41-4.35), and lower DFS (HR 2.57, 95% CI: 1.45-4.57; HR 2.70, 95% CI: 1.45-5.00) than SRI of <180 or 180-210 days. Furthermore, a CRI of more than 42 days was independently associated with higher DM (HR 1.89, 95% CI: 1.17-3.06; HR 1.96, 95% CI: 1.19-3.22), lower OS (HR 2.44, 95% CI: 1.41-4.35; HR 1.92, 95% CI: 1.10-3.33), and lower DFS (HR 1.84, 95% CI: 1.14-2.96; HR 1.82, 95% CI: 1.12-2.94) than a CRI of <28 or 28-42 days. However, SRI and CRI had no significant effect on LRR. CONCLUSIONS: Based on the present findings, the timing of the initiation of RT both after mastectomy and after the completion of adjuvant chemotherapy is crucial for patients with high-risk breast cancer.
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Neoplasias de la Mama , Mastectomía , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Humanos , Recurrencia Local de Neoplasia/patología , Radioterapia Adyuvante , Estudios RetrospectivosRESUMEN
BACKGROUND: Given the lower incidence of lymphoma-related death but higher background mortality in patients with early-stage mucosa-associated lymphoid tissue (MALT) lymphoma, it is critically important to examine how age affects a treatment's survival benefit. METHODS: 9,467 patients with early-stage MALT lymphoma in the Surveillance, Epidemiology, and End Results (SEER) database treated between 2000-2015 were extracted and analyzed. Primary therapy was classified as radiotherapy (n = 3,407), chemotherapy (n = 1,294), and other/unknown treatments including observation (n = 4,766). Inverse probability of treatment weighting (IPTW) was conducted to balance baseline characteristics between groups. Relative survival (RS), standardized mortality ratio (SMR), and transformed Cox regression were conducted to compare survival differences between treatment modalities by controlling for the background mortality. Radiotherapy-age interaction was examined. RESULTS: Across age-groups, early-stage MALT lymphoma patients were at lower risk of lymphoma-related death than death due to other causes. The 10-year overall survival (OS, 73.8 %) and RS (96.6 %) rates were significantly higher, and the SMR (1.14) significantly lower, with radiotherapy than with chemotherapy (OS, 61.7 %; RS, 86.4 %; SMR, 1.54; P < 0.001) or other/unknown treatments (OS, 61.1 %; RS, 87.2 %; SMR, 1.41; P < 0.001). By multivariable analysis and IPTW, radiotherapy remained an independent predictor of better RS (HR 0.81, 95 %CI, 0.73-0.89; P < 0.001). A significant interaction between age and radiotherapy was identified for both RS (Pinteraction = 0.016) and OS (Pinteraction = 0.024), indicating greater benefit in young adults. CONCLUSION: Radiotherapy was associated with significantly better survival in early-stage MALT lymphoma, especially in young adults.
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Linfoma de Células B de la Zona Marginal , Oncología por Radiación , Bases de Datos Factuales , Humanos , Linfoma de Células B de la Zona Marginal/tratamiento farmacológico , Linfoma de Células B de la Zona Marginal/radioterapia , Adulto JovenRESUMEN
Purpose: The aim of this study is to evaluate the role of regional nodal irradiation (RNI) in patients with T1-2N1M0 breast cancer and to identify the subgroup that could benefit from RNI. Methods and materials: A total of 4,243 women with pT1-2N1M0 breast cancer treated at two institutions in China were retrospectively reviewed. Survival rates were calculated by the Kaplan-Meier method and compared by the log-rank test. The association of risk factors with survival outcomes was evaluated using multivariable proportional hazards regression. Results: A total of 932 patients (22.0%) received RNI. At a median follow-up of 5.9 years, the 5-year locoregional recurrence (LRR), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS) rates were 4.0% and 7.2% (P = 0.001), 13.2% and 10.6% (P = 0.465), 85.0% and 84.7% (P = 0.131), and 93.9% and 92.8% (P = 0.004) in the RNI and non-RNI groups, respectively. Multivariate analysis revealed that RNI was an independent prognostic factor for lower LRR (P = 0.001) and longer DFS (P = 0.013). Patients were stratified into low-, intermediate-, and high-risk groups based on the eight non-therapeutic risk factors. RNI significantly decreased the 5-year LRR (2.2% vs. 7.0%, P = 0.001) and improved the 5-year DFS (88.8% vs. 84.9%, P = 0.015) and OS (95.8% vs. 93.9%, P = 0.010) in the intermediate-risk group. However, neither the low-risk group nor the high-risk group had survival benefit from RNI. Conclusion: T1-2N1M0 breast cancer is a heterogeneous disease. We found that RNI only improved survival in the intermediate-risk group. It might be omitted in low-risk patients, and the role of RNI in high-risk patients needs further study.
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Derived from our original nomogram study by using the risk variables from multivariable analyses in the derivation cohort of 1383 patients with extranodal NK/T-cell lymphoma, nasal-type (ENKTCL) who were mostly treated with anthracycline-based chemotherapy, we propose an easily used nomogram-revised risk index (NRI), validated it and compared with Ann Arbor staging, the International Prognostic Index (IPI), Korean Prognostic Index (KPI), and prognostic index of natural killer lymphoma (PINK) for overall survival (OS) prediction by examining calibration, discrimination, and decision curve analysis in a validation cohort of 1582 patients primarily treated with non-anthracycline-based chemotherapy. The calibration of the NRI showed satisfactory for predicting 3- and 5-year OS in the validation cohort. The Harrell's C-index and integrated Brier score (IBS) of the NRI for OS prediction demonstrated a better performance than that of the Ann Arbor staging system, IPI, KPI, and PINK. Decision curve analysis of the NRI also showed a superior outcome. The NRI is a promising tool for stratifying patients with ENKTCL into risk groups for designing clinical trials and for selecting appropriate individualized treatment.
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Toma de Decisiones Clínicas , Linfoma Extranodal de Células NK-T/tratamiento farmacológico , Linfoma Extranodal de Células NK-T/mortalidad , Nomogramas , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica , Área Bajo la Curva , Manejo de la Enfermedad , Femenino , Humanos , Linfoma Extranodal de Células NK-T/diagnóstico , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Reproducibilidad de los Resultados , Análisis de SupervivenciaRESUMEN
BACKGROUND: To compare the survival outcomes between breast-conserving surgery (BCS) and modified radical mastectomy (MRM), and to investigate the role of radiotherapy (RT) in patients with pT1-2N1M0 breast cancer. METHODS: A total of 4262 women with T1-2N1M0 breast cancer treated at two institutions were retrospectively reviewed. A total of 3858 patients underwent MRM, and 832 (21.6%) of them received postoperative RT (MRM + RT). A total of 404 patients received BCS plus postoperative RT (BCS + RT). All patients received axillary lymph node dissection, while 3.8% of them had upfront sentinel node biopsy. The association of survival outcomes with different surgical modalities (BCS vs. MRM) and the role of RT were evaluated using multivariable proportional hazards regression and confirmed by the propensity score-matching (PSM) method. RESULTS: At a median follow-up of 71 months (range of 6-230 months), the 5-year overall survival (OS) rates of the BCS and MRM groups were 96.5 and 92.7%, respectively (P = .001), and the corresponding 5-year disease-free-survival (DFS) and locoregional recurrence (LRR) rates were 92.9 and 84.0%, and 2.0 and 7.0% (P = .001), respectively (P < .001). Multivariate analysis revealed that RT was an independent prognostic factor for improved OS (P = .001) and DFS (P = .009), and decreased LRR (P < .001). However, surgery procedure was not independently associated with either OS (P = .495), DFS (P = .204), or LRR (P = .996), which was confirmed by PSM analysis. CONCLUSION: Postoperative radiotherapy rather than the surgery procedures was associated with superior survival outcomes in patients with T1-2N1M0 breast cancer.
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Neoplasias de la Mama/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/mortalidad , Femenino , Humanos , Persona de Mediana Edad , Análisis de Supervivencia , Resultado del Tratamiento , Adulto JovenRESUMEN
PURPOSE: To investigate the effect of chemotherapy and radiotherapy timing after breast conserving surgery (BCS) on recurrence and survival of women with early-stage breast cancer. PATIENTS AND METHODS: We retrospectively analyzed 900 patients who underwent BCS followed by both adjuvant chemotherapy and radiotherapy. Of these, 488 women received chemotherapy first (CT-first group) while the other 412 received radiotherapy first (RT-first group). Locoregional recurrence (LRR), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS) rates were calculated using the Kaplan-Meier method and further confirmed with propensity-score matching (PSM) and the Cox proportional hazards model. The optimal cut-off value of interval time from surgery to the start of chemotherapy was calculated by Maxstat. RESULTS: The median follow-up was 7.1 years. In pre-match analysis, the CT-first group had a significantly higher 8-year DFS than the RT-first group (90.4% vs. 83.1%, P = 0.005). PSM analysis of 528 patients indicated that the 8-year DFS (91.0% vs. 83.3%, P = 0.005) and DM (8.6% vs. 14.6%, P = 0.017) were significantly better in the CT-first group, but that the OS (P = 0.096) and LRR (P = 0.434) were similar. We found the optimal cut-off value of interval from surgery to chemotherapy was 12 weeks. Patients starting chemotherapy later than 12 weeks after surgery had significantly inferior survival outcomes. CONCLUSION: For women with breast cancer who require both chemotherapy and radiotherapy after BCS, adjuvant chemotherapy should be started within 12 weeks. Delaying the initiation of radiotherapy, for administration of long-course chemotherapy, does not compromise outcomes.
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BACKGROUND: Liver cancer is a devastating disease that has second highest cancer mortality rate worldwide. Although surgical resection or liver transplantation sometimes cures early stage liver cancer, few therapeutic options are available for advanced-stage liver cancer, highlighting the importance of a better understanding of the disease to find novel therapeutic targets. METHODS: Firstly, clinical features of EPS8L3 on liver cancer RNA-seq dataset of The Cancer Genome Atlas (TCGA) database was analyzed, including gene expression levels in tumor tissues in comparison with the normal tissues as well as the patients' OS. To confirm the candidate genes, we used short hairpin RNA (shRNA) to knock down the gene and quantify the cell proliferation, apoptosis, and migration. Then micro-array analysis was did to investigate the intracellular mechanisms of EPS8L3. Moreover, to gain further insights into the translational value of the findings, we treated the liver cancer cells with Sorafenib after knocking down the candidate gene, in order to interrogate the combinatorial inhibitory effects on cell metabolism. RESULTS: As a result, by comparing gene expression profiles of normal liver and cancerous tissues, we find that epidermal growth factor receptor kinase substrate 8-like protein 3 (EPS8L3), a gene with unknown function, is upregulated in liver cancer, and is associated with poor prognosis. Further gene set analyses on liver cancer cells revealed that EPS8L3 is pertinent to cell division and proliferation. Indeed, knocking down EPS8L3 inhibits cell proliferation and migration, and triggers apoptosis in vitro. Additionally, when inoculated into mice, EPS8L3 knocked down cells exhibit slower growth rate. Moreover, EPS8L3 expression can substantially increase the efficacy of low dosage of Sorafenib treatment. Furthermore, the results of immunohistochemical staining of 90 paired liver cancer and adjacent normal samples demonstrated high expression of EPS8L3 yields poor prognosis in Chinese liver cancer patients. CONCLUSIONS: Collectively, our results suggest that EPS8L3 has pivotal oncogenic functions in liver cancer and we propose that EPS8L3 could be a potential therapeutic target to treat liver cancer.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antineoplásicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Sorafenib/farmacología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo , Femenino , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Invasividad Neoplásica , Transducción de Señal , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND AND PURPOSE: We investigated the locoregional effect of trastuzumab, and determined whether patients with human epidermal growth factor receptor (HER)2-positive breast cancer (BC) treated with trastuzumab could achieve comparable efficacy to that of patients with HER2-negative BC. MATERIALS AND METHODS: This was post hoc analyses of data of 793 BC patients from a randomized controlled trial comparing post-mastectomy hypofractionated radiotherapy with conventional fractionated radiotherapy. Survival rates were analyzed by the Kaplan-Meier method and compared by the log-rank test. RESULTS: Patients were classified into three groups: HER2-negative (HER2-; n = 547), HER2-positve with trastuzumab (HER2+ + T; n = 136), and HER2-positive without trastuzumab (HER2+ - T; n = 110). The HER2+ + T group had significantly lower locoregional recurrence (LRR, 6.0% vs. 13.9%), distant metastasis (DM, 17.4% vs. 33.8%) and higher disease-free survival (DFS, 81.2% vs. 61.9%) at 5 years than that of the HER2+ - T group (P <.05). The HER2- group had significantly lower LRR (6.8% vs. 13.9%), DM (22.4% vs. 33.8%) and higher DFS (76.1% vs. 61.9%) at 5 years than that of the HER2+ - T group (P <.05). The difference in LRR, DM and DFS at 5 years was not significant between the HER2+ + T group and HER2- group (P >.05). Different annual LRR patterns was found among groups according to HR status. CONCLUSION: Trastuzumab reduces LRR in patients with locally advanced HER2-positive BC who have received post-mastectomy radiotherapy. It provides comparable DFS to that with patients with HER2-negative BC.
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Laminaria japonica gametophytic cells were cultivated in a photobioreactor under continuous shear stress (0-1000 r/min) in 60 hours and the following static cultivation within 23.5 days. The content of chlorophyll a reached the maximum value of 2.36 mg/L at the end of continuous shear stress when the agitation speed was 90 r/min, while the chlorophyll a (chl a) concentration decreased quickly and nitrogen and phosphorus were released under high shear force (270-1000 r/min). The cell injury ratio at 1000r/min was as 18 times as that of the control. During the recovery course, gametophytic cells showed themselves distinct recovery capability at all agitation speeds. Furthermore, the content of chl a is a more exact index as biomass than dry cells weight (DCW). Besides cell injury ratio, the liberation of phosphorus demonstrates the cells injury.