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1.
Ann Oncol ; 35(4): 364-380, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38244928

RESUMEN

BACKGROUND: Resistance to therapies that target homologous recombination deficiency (HRD) in breast cancer limits their overall effectiveness. Multiple, preclinically validated, mechanisms of resistance have been proposed, but their existence and relative frequency in clinical disease are unclear, as is how to target resistance. PATIENTS AND METHODS: Longitudinal mutation and methylation profiling of circulating tumour (ct)DNA was carried out in 47 patients with metastatic BRCA1-, BRCA2- or PALB2-mutant breast cancer treated with HRD-targeted therapy who developed progressive disease-18 patients had primary resistance and 29 exhibited response followed by resistance. ctDNA isolated at multiple time points in the patient treatment course (before, on-treatment and at progression) was sequenced using a novel >750-gene intron/exon targeted sequencing panel. Where available, matched tumour biopsies were whole exome and RNA sequenced and also used to assess nuclear RAD51. RESULTS: BRCA1/2 reversion mutations were present in 60% of patients and were the most prevalent form of resistance. In 10 cases, reversions were detected in ctDNA before clinical progression. Two new reversion-based mechanisms were identified: (i) intragenic BRCA1/2 deletions with intronic breakpoints; and (ii) intragenic BRCA1/2 secondary mutations that formed novel splice acceptor sites, the latter being confirmed by in vitro minigene reporter assays. When seen before commencing subsequent treatment, reversions were associated with significantly shorter time to progression. Tumours with reversions retained HRD mutational signatures but had functional homologous recombination based on RAD51 status. Although less frequent than reversions, nonreversion mechanisms [loss-of-function (LoF) mutations in TP53BP1, RIF1 or PAXIP1] were evident in patients with acquired resistance and occasionally coexisted with reversions, challenging the notion that singular resistance mechanisms emerge in each patient. CONCLUSIONS: These observations map the prevalence of candidate drivers of resistance across time in a clinical setting, information with implications for clinical management and trial design in HRD breast cancers.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Femenino , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Recombinación Homóloga , Mutación , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Proteína 1 de Unión al Supresor Tumoral P53
2.
Ann Oncol ; 32(1): 58-65, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33098992

RESUMEN

BACKGROUND: In the TNT trial of triple negative breast cancer (NCT00532727), germline BRCA1/2 mutations were present in 28% of carboplatin responders. We assessed quantitative measures of structural chromosomal instability (CIN) to identify a wider patient subgroup within TNT with preferential benefit from carboplatin over docetaxel. PATIENTS AND METHODS: Copy number aberrations (CNAs) were established from 135 formalin-fixed paraffin-embedded primary carcinomas using Illumina OmniExpress SNP-arrays. Seven published [allelic imbalanced CNA (AiCNA); allelic balanced CNA (AbCNA); copy number neutral loss of heterozygosity (CnLOH); number of telomeric allelic imbalances (NtAI); BRCA1-like status; percentage of genome altered (PGA); homologous recombination deficiency (HRD) scores] and two novel [Shannon diversity index (SI); high-level amplifications (HLAMP)] CIN-measurements were derived. HLAMP was defined based on the presence of at least one of the top 5% amplified cytobands located on 1q, 8q and 10p. Continuous CIN-measurements were divided into tertiles. All nine CIN-measurements were used to analyse objective response rate (ORR) and progression-free survival (PFS). RESULTS: Patients with tumours without HLAMP had a numerically higher ORR and significantly longer PFS in the carboplatin (C) than in the docetaxel (D) arm [56% (C) versus 29% (D), PHLAMP,quiet = 0.085; PFS 6.1 months (C) versus 4.1 months (D), Pinteraction/HLAMP = 0.047]. In the carboplatin arm, patients with tumours showing intermediate telomeric NtAI and AiCNA had higher ORR [54% (C) versus 20% (D), PNtAI,intermediate = 0.03; 62% (C) versus 33% (D), PAiCNA,intermediate = 0.076]. Patients with high AiCNA and PGA had shorter PFS in the carboplatin arm [3.4 months (high) versus 5.7 months (low/intermediate); and 3.8 months (high) versus 5.6 months (low/intermediate), respectively; Pinteraction/AiCNA = 0.027, Padj.interaction/AiCNA = 0.125 and Pinteraction/PGA = 0.053, Padj.interaction/PGA = 0.176], whilst no difference was observed in the docetaxel arm. CONCLUSIONS: Patients with tumours lacking HLAMP and demonstrating intermediate CIN-measurements formed a subgroup benefitting from carboplatin relative to docetaxel treatment within the TNT trial. This suggests a complex and paradoxical relationship between the extent of genomic instability in primary tumours and treatment response in the metastatic setting.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama Triple Negativas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores , Carboplatino/uso terapéutico , Inestabilidad Cromosómica/genética , Humanos , Fenotipo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética
3.
Breast Cancer Res Treat ; 168(1): 169-178, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29177605

RESUMEN

BACKGROUND: Intergroup Exemestane Study (IES) was a randomised study that showed a survival benefit of switching adjuvant endocrine therapy after 2-3 years from tamoxifen to exemestane. This PathIES aimed to assess the role of immunohistochemical (IHC)4 score in determining the relative sensitivity to either tamoxifen or sequential treatment with tamoxifen and exemestane. PATIENTS AND METHODS: Primary tumour samples were available for 1274 patients (27% of IES population). Only patients for whom the IHC4 score could be calculated (based on oestrogen receptor, progesterone receptor, HER2 and Ki67) were included in this analysis (N = 430 patients). The clinical score (C) was based on age, grade, tumour size and nodal status. The association of clinicopathological parameters, IHC4(+C) scores and treatment effect with time to distant recurrence-free survival (TTDR) was assessed in univariable and multivariable Cox regression analyses. A modified clinical score (PathIEscore) (N = 350) was also estimated. RESULTS: Our results confirm the prognostic importance of the original IHC4, alone and in conjunction with clinical scores, but no significant difference with treatment effects was observed. The combined IHC4 + Clinical PathIES score was prognostic for TTDR (P < 0.001) with a hazard ratio (HR) of 5.54 (95% CI 1.29-23.70) for a change from 1st quartile (Q1) to Q1-Q3 and HR of 15.54 (95% CI 3.70-65.24) for a change from Q1 to Q4. CONCLUSION: In the PathIES population, the IHC4 score is useful in predicting long-term relapse in patients who remain disease-free after 2-3 years. This is a first trial to suggest the extending use of IHC4+C score for prognostic indication for patients who have switched endocrine therapies at 2-3 years and who remain disease-free after 2-3 years.


Asunto(s)
Androstadienos/uso terapéutico , Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/terapia , Recurrencia Local de Neoplasia/epidemiología , Tamoxifeno/uso terapéutico , Anciano , Androstadienos/farmacología , Antineoplásicos Hormonales/farmacología , Mama/patología , Mama/cirugía , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Quimioterapia Adyuvante/métodos , Supervivencia sin Enfermedad , Método Doble Ciego , Resistencia a Antineoplásicos , Femenino , Humanos , Inmunohistoquímica , Mastectomía , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Pronóstico , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Tamoxifeno/farmacología , Factores de Tiempo
4.
Ann Oncol ; 26(1): 70-74, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25355719

RESUMEN

BACKGROUND: Retrospective analyses of NSABP B20 and SWOG 8814 showed a large benefit of chemotherapy in patients with ER-positive tumors and high OncotypeDX Recurrence Score (RS≥31). However, it might be possible that both studies may be contaminated by non-luminal tumors, especially in high-risk RS group. METHODS: We conducted simulations in order to obtain a better understanding of how the NSABP B20 and SWOG 8814 results would have been if non-luminal breast cancer would have been excluded. Simulations were done separately for the node-negative and node-positive cohorts. RESULTS AND CONCLUSION: The results of the simulations suggest that the non-luminal tumors are augmenting the apparent benefit of chemotherapy, but do not appear to be responsible for the entire effect. These simulations could provide information about the potential influence of contamination by unexpected tumor subtypes on the future results of TAILORx and RxPONDER clinical trials.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Simulación por Computador , Receptores de Estrógenos/metabolismo , Biomarcadores de Tumor , Neoplasias de la Mama/genética , Quimioterapia Adyuvante , Femenino , Humanos , Recurrencia Local de Neoplasia/tratamiento farmacológico
5.
Ann Oncol ; 26(9): 1890-1897, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26002610

RESUMEN

BACKGROUND: Intergroup Exemestane Study (IES) was a randomised study that showed a survival benefit of switching adjuvant endocrine therapy after 2-3 years from tamoxifen to exemestane. PathIES aimed to assess the potential prognostic and predictive value of ERß1 and ERß2 expression in primary tumours in order to determine benefit in the two treatment arms. PATIENTS AND METHODS: Primary tumour samples were available for 1256 patients (27% IES population). ERß1 and ERß2 expression was dichotomised at the median IHC score (high if ERß1 ≥ 191, ERß2 ≥ 164). Hazard ratios (HRs) were estimated by multivariable Cox proportional hazards models adjusting for clinicopathological factors. Treatment effects with biomarker expressions were determined by interaction tests. Analysis explored effects of markers both as a continuous variable and with dichotomised cut-offs. RESULTS: Neither ERß1 nor ERß2 were associated with disease-free survival (DFS) or overall survival (OS) in the whole cohort. In patients treated with continued tamoxifen, high ERß1 expression compared with low was associated with better DFS [HR = 0.38:95% confidence interval (CI) 0.21-0.68, P = 0.001]. DFS benefit of exemestane over tamoxifen (HR = 0.40:95% CI 0.22-0.70) was found in the low ERß1 subgroup (interaction P = 0.01). No significant difference with treatment was observed for ERß2 expression in either DFS or OS. CONCLUSION: In the PathIES population, exemestane appeared to be superior to tamoxifen among patients with low ERß1 expression but not in those with high ERß1 expression. This is the first trial of its kind to report a parameter potentially predicting benefit of an aromatase inhibitor when compared with tamoxifen and an independent validation is warranted.


Asunto(s)
Androstadienos/uso terapéutico , Biomarcadores de Tumor/genética , Neoplasias de la Mama/tratamiento farmacológico , Receptor beta de Estrógeno/genética , Tamoxifeno/uso terapéutico , Anciano , Antineoplásicos/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Supervivencia sin Enfermedad , Método Doble Ciego , Receptor beta de Estrógeno/biosíntesis , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Resultado del Tratamiento
6.
Br J Cancer ; 111(8): 1532-41, 2014 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-25101563

RESUMEN

BACKGROUND: In this study, we evaluated the ability of gene expression profiles to predict chemotherapy response and survival in triple-negative breast cancer (TNBC). METHODS: Gene expression and clinical-pathological data were evaluated in five independent cohorts, including three randomised clinical trials for a total of 1055 patients with TNBC, basal-like disease (BLBC) or both. Previously defined intrinsic molecular subtype and a proliferation signature were determined and tested. Each signature was tested using multivariable logistic regression models (for pCR (pathological complete response)) and Cox models (for survival). Within TNBC, interactions between each signature and the basal-like subtype (vs other subtypes) for predicting either pCR or survival were investigated. RESULTS: Within TNBC, all intrinsic subtypes were identified but BLBC predominated (55-81%). Significant associations between genomic signatures and response and survival after chemotherapy were only identified within BLBC and not within TNBC as a whole. In particular, high expression of a previously identified proliferation signature, or low expression of the luminal A signature, was found independently associated with pCR and improved survival following chemotherapy across different cohorts. Significant interaction tests were only obtained between each signature and the BLBC subtype for prediction of chemotherapy response or survival. CONCLUSIONS: The proliferation signature predicts response and improved survival after chemotherapy, but only within BLBC. This highlights the clinical implications of TNBC heterogeneity, and suggests that future clinical trials focused on this phenotypic subtype should consider stratifying patients as having BLBC or not.


Asunto(s)
Antineoplásicos/uso terapéutico , Análisis de Supervivencia , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Resultado del Tratamiento , Neoplasias de la Mama Triple Negativas/fisiopatología
7.
Breast Cancer Res Treat ; 148(3): 581-90, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25395314

RESUMEN

Neoadjuvant endocrine therapy is an alternative to chemotherapy for women with oestrogen receptor (ER)-positive early breast cancer (BC). We aimed to assess feasibility of recruiting patients to a study comparing chemotherapy versus endocrine therapy in postmenopausal women with ER-rich primary BC, and response as well as translational endpoints were assessed. Patients requiring neoadjuvant therapy were randomised to chemotherapy: 6 × 3-weekly cycles FE100C or endocrine therapy: letrozole 2.5 mg, daily for 18-23 weeks. Primary endpoints were recruitment feasibility and tissue collection. Secondary endpoints included clinical, radiological and pathological response rates, quality of life and translational endpoints. 63/80 patients approached were eligible, of those 44 (70, 95% CI 57-81) were randomised. 12 (54.5, 95% CI 32.2-75.6) chemotherapy patients showed radiological objective response compared with 13 (59.1, 95% CI 36.4-79.3) letrozole patients. Compared with baseline, mean Ki-67 levels fell in both groups at days 2-4 and at surgery [fold change: 0.24 (95% CI 0.12-0.51) and 0.24; (95% CI 0.15-0.37), respectively]. Plasma total cfDNA levels rose from baseline to week 8 [fold change: chemotherapy 2.10 (95% CI 1.47-3.00), letrozole 1.47(95% CI 0.98-2.20)], and were maintained at surgery in the chemotherapy group [chemotherapy 2.63; 95% CI 1.56-4.41), letrozole 0.95 (95% CI 0.71-1.26)]. An increase in plasma let-7a miRNA was seen at surgery for patients with objective radiological response to chemotherapy. Recruitment and tissue collection endpoints were met; however, a larger trial was deemed unfeasible due to slow accrual. Both regimens were equally efficacious. Dynamic changes were seen in Ki-67 and circulating biomarkers in both groups with increases in cfDNA and let-7a miRNA persisting until surgery for chemotherapy patients.


Asunto(s)
Antineoplásicos Hormonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Inhibidores de la Aromatasa/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Terapia Neoadyuvante , Adulto , Antineoplásicos Hormonales/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/sangre , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Letrozol , MicroARNs/sangre , Persona de Mediana Edad , Nitrilos/administración & dosificación , Posmenopausia , Calidad de Vida , Receptores de Estrógenos/metabolismo , Triazoles/administración & dosificación
8.
Br J Cancer ; 107(5): 800-7, 2012 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-22850554

RESUMEN

BACKGROUND: Predict (www.predict.nhs.uk) is an online, breast cancer prognostication and treatment benefit tool. The aim of this study was to incorporate the prognostic effect of HER2 status in a new version (Predict+), and to compare its performance with the original Predict and Adjuvant!. METHODS: The prognostic effect of HER2 status was based on an analysis of data from 10 179 breast cancer patients from 14 studies in the Breast Cancer Association Consortium. The hazard ratio estimates were incorporated into Predict. The validation study was based on 1653 patients with early-stage invasive breast cancer identified from the British Columbia Breast Cancer Outcomes Unit. Predicted overall survival (OS) and breast cancer-specific survival (BCSS) for Predict+, Predict and Adjuvant! were compared with observed outcomes. RESULTS: All three models performed well for both OS and BCSS. Both Predict models provided better BCSS estimates than Adjuvant!. In the subset of patients with HER2-positive tumours, Predict+ performed substantially better than the other two models for both OS and BCSS. CONCLUSION: Predict+ is the first clinical breast cancer prognostication tool that includes tumour HER2 status. Use of the model might lead to more accurate absolute treatment benefit predictions for individual patients.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/enzimología , Modelos Estadísticos , Receptor ErbB-2/biosíntesis , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Adulto Joven
9.
Ann Oncol ; 23(11): 2866-2873, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22532584

RESUMEN

BACKGROUND: ER-positive (ER+) breast cancer includes all of the intrinsic molecular subtypes, although the luminal A and B subtypes predominate. In this study, we evaluated the ability of six clinically relevant genomic signatures to predict relapse in patients with ER+ tumors treated with adjuvant tamoxifen only. METHODS: Four microarray datasets were combined and research-based versions of PAM50 intrinsic subtyping and risk of relapse (PAM50-ROR) score, 21-gene recurrence score (OncotypeDX), Mammaprint, Rotterdam 76 gene, index of sensitivity to endocrine therapy (SET) and an estrogen-induced gene set were evaluated. Distant relapse-free survival (DRFS) was estimated by Kaplan-Meier and log-rank tests, and multivariable analyses were done using Cox regression analysis. Harrell's C-index was also used to estimate performance. RESULTS: All signatures were prognostic in patients with ER+ node-negative tumors, whereas most were prognostic in ER+ node-positive disease. Among the signatures evaluated, PAM50-ROR, OncotypeDX, Mammaprint and SET were consistently found to be independent predictors of relapse. A combination of all signatures significantly increased the performance prediction. Importantly, low-risk tumors (>90% DRFS at 8.5 years) were identified by the majority of signatures only within node-negative disease, and these tumors were mostly luminal A (78%-100%). CONCLUSIONS: Most established genomic signatures were successful in outcome predictions in ER+ breast cancer and provided statistically independent information. From a clinical perspective, multiple signatures combined together most accurately predicted outcome, but a common finding was that each signature identified a subset of luminal A patients with node-negative disease who might be considered suitable candidates for adjuvant endocrine therapy alone.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Biomarcadores de Tumor/genética , Neoplasias de la Mama/tratamiento farmacológico , Receptores de Estrógenos/metabolismo , Tamoxifeno/uso terapéutico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Quimioterapia Adyuvante , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Genómica , Humanos , Pronóstico
10.
Breast Cancer Res Treat ; 128(1): 127-36, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21465170

RESUMEN

UNLABELLED: Taxanes and anthracyclines improve the outcome of early breast cancer, although the benefit is limited to a small proportion of patients and are toxic. We prospectively looked for predictors of response to these drugs. EXPERIMENTAL DESIGN: Four cycles of doxorubicin (75 mg/m²) or docetaxel (100 mg/m²) were compared as presurgical chemotherapy for breast cancer. Biomarkers were determined by immunohistochemistry and fluorescent in situ hybridization using prechemotherapy core biopsies. Tumors were also classified into one of the molecular intrinsic subtypes using an immunohistochemical panel of five biomarkers and genomic profiles. Single genes and intrinsic subtypes were correlated with response to doxorubicin versus docetaxel. Among the 204 evaluable patients, significant predictors of sensitivity in multivariate analysis were low topo2a expression and ER-negative status for doxorubicin and small tumor size and ER-negative status for docetaxel. Predictors of resistance in multivariate analysis were triple-negative status (ER/PgR/HER2 negative by IHC/FISH) for doxorubicin, and high TNM stage for docetaxel. Triple-negative tumors were associated with topo2a overexpression more than the other subtypes. In 94 patients with gene expression profiles, docetaxel was superior to doxorubicin in the basal-like subtype (good pathological response rate - PCR + class I of 56 vs. 0%; P = 0.034); no significant differences were observed in the other subtypes when comparing these two drugs. Low topo2a expression and ER-negative status were predictors of response to doxorubicin, while small tumor size and ER-negative status predicted response to docetaxel. Docetaxel was superior to doxorubicin in triple-negative/basal-like tumors, while no significant differences were seen in the remaining intrinsic subtypes.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Doxorrubicina/uso terapéutico , Resistencia a Antineoplásicos/genética , Genes Relacionados con las Neoplasias , Taxoides/uso terapéutico , Adulto , Anciano , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Lobular/tratamiento farmacológico , ADN-Topoisomerasas de Tipo II/genética , ADN-Topoisomerasas de Tipo II/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Docetaxel , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Humanos , Persona de Mediana Edad , Análisis Multivariante , Resultado del Tratamiento
11.
Can J Gastroenterol ; 24(1): 33-9, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20186354

RESUMEN

BACKGROUND: The wait time from cancer diagnosis to treatment has been a recent focus of cancer care in Canada. OBJECTIVE: To examine the trends in wait times from patient presentation to treatment (overall health system wait time [OWT]) for colorectal cancer (CRC). METHODS: Patients with colorectal adenocarcinomas, diagnosed between 2001 and 2005, and their first definitive treatments were identified from the population-based Manitoba Cancer Registry (Winnipeg, Manitoba). By linkage to Manitoba Health and Healthy Living's administrative databases, a patient's first gastrointestinal investigation (abdominal radiological imaging, lower gastrointestinal endoscopy or fecal occult blood test) before CRC diagnosis was identified. The index contact with the health care system was estimated from the date of the visit with the physician who ordered the first gastroenterological investigation. The OWT was defined as the time from the index contact to the first treatment, while diagnostic delay was defined as the time from the index contact to the diagnosis of CRC. Multivariate Cox regression analysis was performed to determine independent predictors of OWT. RESULTS: The OWT was estimated for 2552 cases of CRC over the five years that were examined. The median OWT increased from 61 days in 2001 to 95 days in 2005 (P<0.001). Most of the increase was in diagnostic wait times (median of 44 days in 2001 versus 64 days in 2005 [P<0.001]). Year of diagnosis, older age, urban residence and diagnosis at a teaching facility were independent predictors of OWT. CONCLUSIONS: The OWT from presentation to treatment of CRC in Manitoba steadily increased between 2001 and 2005, mostly due to diagnostic delays.


Asunto(s)
Adenocarcinoma/diagnóstico , Neoplasias Colorrectales/diagnóstico , Diagnóstico Tardío/estadística & datos numéricos , Listas de Espera , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Gastroenterología/estadística & datos numéricos , Accesibilidad a los Servicios de Salud , Humanos , Masculino , Manitoba , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Derivación y Consulta/estadística & datos numéricos , Sistema de Registros , Estudios Retrospectivos , Factores de Tiempo , Población Urbana
12.
Foot Ankle Int ; 27(10): 771-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17054876

RESUMEN

BACKGROUND: Osteomyelitis in the foot of a diabetic individual is a common complication of peripheral neuropathy, peripheral vascular disease, and infection. Operative facilities and home intravenous antibiotic therapy programs may not be available in remote or rural communities. Limited data are available regarding the treatment results of oral antimicrobial therapy, with or without limited office debridement for diabetic foot osteomyelitis. METHODS: This retrospective medical record review of 325 consecutive diabetic patients who were evaluated at a multidisciplinary foot clinic identified 94 (29%) patients with 117 episodes of osteomyelitis. The most common group of organisms isolated were aerobic gram-positive cocci, and the single most frequent organism was Staphylococcus aureus. A mean of 1.6 +/- 0.8 (range 1 to 4) pathogens were recovered per episode of osteomyelitis. Therapy was guided by culture results. There were 93 episodes of osteomyelitis (79 patients) that were treated with a mean of 3 +/- 1 oral antimicrobial agents (with or without an initial short course of intravenous antimicrobial agents) and had adequate followup to evaluate outcome of treatment; office treatment included bone debridement in 26 (28%) and toe amputation in nine (10%) of the 93 episodes (79 patients). RESULTS: Of the 93 episodes treated with oral antimicrobial agents (with or without an initial short course of intravenous antimicrobial agents), 75 (80.5%) episodes were put into remission. Mean duration of oral antimicrobial therapy was 40 +/- 30 weeks. Mean relapse-free followup duration was 50 +/- 50 weeks. CONCLUSIONS: Diabetic foot osteomyelitis was effectively managed with oral antimicrobial therapy with or without limited office debridement in most patients. This regimen may be especially useful in communities where infectious disease specialists and operative resources are limited.


Asunto(s)
Antibacterianos/uso terapéutico , Pie Diabético/microbiología , Huesos del Pie/microbiología , Osteomielitis/tratamiento farmacológico , Administración Oral , Amputación Quirúrgica , Antibacterianos/administración & dosificación , Desbridamiento , Pie Diabético/tratamiento farmacológico , Pie Diabético/cirugía , Combinación de Medicamentos , Femenino , Estudios de Seguimiento , Huesos del Pie/cirugía , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/cirugía , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/cirugía , Humanos , Inyecciones Intravenosas , Masculino , Huesos Metatarsianos/microbiología , Huesos Metatarsianos/cirugía , Persona de Mediana Edad , Osteomielitis/microbiología , Osteomielitis/cirugía , Recurrencia , Estudios Retrospectivos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/cirugía , Factores de Tiempo , Falanges de los Dedos del Pie/microbiología , Falanges de los Dedos del Pie/cirugía , Resultado del Tratamiento
13.
Cancer Res ; 46(1): 218-23, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3940192

RESUMEN

The mechanism of uptake of Adriamycin was investigated in chick embryo heart and liver cells and in murine L5178Y lymphoblasts in vitro. Drug uptake at 4 degrees C for 15 s due to rapid association accounted for a cell:medium distribution ratio of 104 +/- 14 (SE) in heart cells, 10.2 +/- 1.3 in liver cells, and 10.3 +/- 1.5 in L5178Y lymphoblasts. On thin-layer chromatographic analysis, 98% of the radioactivity migrated with the mobility of intact drug, suggesting that drug metabolism was negligible for at least 30 min in both heart and tumor cells. A time course of drug uptake was somewhat different in heart cells compared to that noted for liver or L5178Y cells. The steady state for drug uptake was reached more promptly in heart cells; apparent equilibrium was observed at 6 min in heart cells, at approximately 20 min in L5178Y lymphoblasts, but was not attained by 25 min in liver cells. Temperature dependence of drug uptake also differed in the three cell types; drug uptake was most temperature sensitive in L5178Y cells, intermediate in liver cells, and least temperature dependent in heart cells. Separation of heart, liver, and leukemic cells into membrane and cytosol fractions demonstrated that, at 1 and 30 min, more than 75% of the drug was associated with the membrane fraction. Trichloroacetic acid extraction of cell constituents revealed that, at 1 min, the acid-soluble fraction amounted to 32 +/- 2% of radioactivity in heart cells and 37 +/- 2% in L5178Y cells. Ethanol extraction of these cells demonstrated that, at 1 min, ethanol-soluble components accounted for 49 +/- 2% of radioactivity in heart cells and 27 +/- 2% in leukemic cells. The finding of a large component of rapid association together with evidence of prompt drug binding to cellular constituents made evaluation of unidirectional drug influx impractical. Accordingly, an investigation was undertaken of Adriamycin efflux from chick embryo heart and liver cells and L5178Y lymphoblasts, after the cells had been loaded with drug for various time intervals. In all three cell types, efflux was rapid down to a plateau level, representing nonexchangeable drug. As the period of time for loading cells was increased, there was a progressive rise in the level of nonexchangeable drug. Equilibration of the nonexchangeable pool occurred more rapidly in heart cells than in either liver or leukemic cells.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Doxorrubicina/metabolismo , Animales , Transporte Biológico , Compartimento Celular , Membrana Celular/metabolismo , Embrión de Pollo , Cinética , Hígado/metabolismo , Linfocitos/metabolismo , Ratones , Miocardio/metabolismo , Temperatura
14.
J Clin Oncol ; 15(6): 2254-61, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9196138

RESUMEN

PURPOSE: To study the sequential changes in the intestinal absorption of an oral pentose probe, D-xylose, in patients receiving therapy for untreated acute myeloid leukemia (AML), and to correlate these changes to infectious morbidity. PATIENTS AND METHODS: Serial D-xylose absorption studies were conducted in 110 consecutive adult patients admitted to a university-affiliated tertiary care hospital for remission-induction therapy for untreated newly diagnosed AML. Serial serum D-xylose levels were obtained 1 hour after a 5-g oral dose of D-xylose at baseline and weekly for 4 weeks until marrow recovery. These results were correlated with invasive infection using multivariate techniques. RESULTS: The mean (+/- SEM) serum D-xylose levels were 0.88 +/- 0.03, 0.69 +/- 0.03, 0.58 +/- 0.02, 0.53 +/- 0.02, and 0.73 +/- 0.02 mmol/L at baseline and weeks 1 to 4, respectively (P < .0001, analysis of variance [AN-OVA]). Time to malabsorption varied with induction regimen (P = .007, log-rank test). Bloodstream infections during week 2 correlated with malabsorption (P = .007). Neutropenic enterocolitis correlated independently with induction regimen (P = .009), malabsorption at week 2 (P = .02), and the development of candidemia (P = .005). Hepatosplenic fungal infection correlated with induction regimen (P = .03), malabsorption at week 2 (P = .02), and fever at diagnosis (P = .003). Malabsorption was unrelated to the duration of severe neutropenia and the administration of parenteral nutrition. CONCLUSION: Serial D-xylose absorption studies in subjects with AML produced a characteristic profile of cytotoxic therapy-related damage to the functional integrity of the intestinal epithelium that was regimen dependent, myelosuppression independent, and predictive for invasive infectious complications. Further study to validate these observations appears warranted.


Asunto(s)
Antineoplásicos/efectos adversos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/metabolismo , Síndromes de Malabsorción/inducido químicamente , Xilosa/farmacocinética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Absorción Intestinal/efectos de los fármacos , Síndromes de Malabsorción/metabolismo , Masculino , Persona de Mediana Edad , Micosis/inducido químicamente , Micosis/metabolismo , Neutropenia/inducido químicamente , Neutropenia/metabolismo , Inducción de Remisión , Factores de Riesgo , Xilosa/sangre
15.
J Clin Oncol ; 17(11): 3426-30, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10550137

RESUMEN

PURPOSE: To determine if inhibition of stem-cell activity induced by granulocyte-macrophage colony-stimulating factor ([GM-CSF]; Sargramostim; Immunex Corporation, Seattle, WA) withdrawal or priming protects hematopoietic stem cells from the cytotoxic effects of adjuvant chemotherapy for early-stage breast cancer. PATIENTS AND METHODS: Serial blood counts were performed in 20 women with early-stage breast cancer receiving four courses of cyclophosphamide and doxorubicin chemotherapy. By a double-blind, placebo-controlled, balanced randomization, subjects received GM-CSF priming on days 5 to 1 for courses 1 and 3 or courses 2 and 4. RESULTS: Compared with before priming, after priming the times to neutrophil nadir (12.8 +/- 2.5 days v 14.8 +/- 1.5 days, respectively; P =.0001) and platelet nadir (mean +/- SD, 10.1 +/- 1.9 days v 11.1 +/- 2.2 days, P <.05) were shorter, indicating a shift of cytotoxicity to later progenitors. The neutrophil nadir was similar with and without priming (mean +/- SD, 490 +/- 310/microL v 550 +/- 350/microL, respectively; P =.2); however, on day 16 the mean neutrophil count was higher (mean +/- SD, 1030 +/- 580/microL v 690 +/- 370/microL, P =.004), and the proportion of patients with a neutrophil count less than 500/microL was lower after priming than before (six of 35 or 17. 1% v 12 of 34 or 35.3%, respectively; P =.04). The platelet nadir was higher (mean +/- SD, 166,000 +/- 51,000/microL after priming v 151,000 +/- 45,000/microL before priming, P =.007), and the duration of thrombocytopenia, ie, a platelet count less than 150,000/microL, was shorter (1.5 +/- 2.1 days v 2.8 +/- 2.9 days, P =.0025) after priming. Episodes of fever and neutropenia were not observed. CONCLUSIONS: GM-CSF priming from days 5 to 1 before doxorubicin and cyclophosphamide chemotherapy was associated with an earlier neutrophil and platelet nadir. On day 16, a higher mean neutrophil count and a lower proportion of patients with severe (< 500/microL) neutropenia were observed. Beneficial effects on the severity and duration of thrombocytopenia were also noted. These observations support the hypothesis that GM-CSF priming protects hematopoietic progenitors from the cytotoxic effects of chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Adulto , Anciano , Ciclofosfamida/administración & dosificación , Método Doble Ciego , Doxorrubicina/administración & dosificación , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos y Macrófagos/efectos adversos , Humanos , Persona de Mediana Edad
16.
J Cereb Blood Flow Metab ; 14(3): 510-8, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8163594

RESUMEN

We studied cerebral autoregulation by analyzing cerebral pressure-flow curves during cardiopulmonary bypass (CPB) with alpha-stat (alpha-stat) acid-base management at 28 (n = 9) and 37 degrees C (n = 9) in two groups of dogs. Cerebral blood flow (CBF) and cerebral metabolic rate for oxygen (CMRO2) were determined multiple times in each animal over an extensive range of cerebral perfusion pressure (CPP). The CPP was altered by changing perfusion flow rate. The dependence of CBF on CPP during normothermic and moderate hypothermic CPB was assessed using a block design analysis of covariance with CPP as the covariate. We anticipated maximal statistical power with this analysis to define if cerebral autoregulation was intact. This method of statistical analysis was compared with the conventional interpretation by linear regression analysis. Animals were administered sodium thiopental until an isoelectric electroencephalogram was obtained to assure stable depth of anesthesia independently of temperature effects. The animals were randomly assigned to either temperature group. The CBF was determined by injection of radioactive microspheres at each of five target CPPs randomly allocated (50, 60, 70, 80, and 90 mm Hg). The brain oxygen content difference was defined as arterial minus superior sagittal sinus (SSS) oxygen content. No difference in CPP, hemoglobin, arterial carbon dioxide tension, or pH was seen between groups at any time period. In both groups, total CBF (tCBF) increased significantly with increasing CPP (p = 0.012 and 0.017 for normothermic and hypothermic CPB, respectively; CPP as covariate). The between-group difference in slopes (CPP x temperature effect) approached statistical significance (p = 0.059).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Presión Sanguínea , Temperatura Corporal , Puente Cardiopulmonar , Circulación Cerebrovascular , Hipotermia Inducida , Análisis de Varianza , Animales , Encéfalo/metabolismo , Perros , Consumo de Oxígeno , Valores de Referencia
17.
Int J Radiat Oncol Biol Phys ; 34(1): 41-7, 1996 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-12118564

RESUMEN

PURPOSE: This study was done to review long-term results of radical radiotherapy for prostate cancer. METHODS AND MATERIALS: The records of 674 patients with Stage T1a, T1b, T2a, T2b, T3, and any T,N1,M0 disease, treated with external beam radiotherapy between January 1, 1967 and December 1987, were reviewed. These patients were treated to an average total dose of 66 Gy, with an average fractional dose of 2.05 Gy, using megavoltage. The duration of follow-up for surviving patients ranged from a minimum of 7 years to more than 20 years. RESULTS: The survival for 151 Stage T1a,T1b patients was 98.5% at 5 years, 93.6% at 10 years, and 75.2% at 15 years. Survival for 346 Stage T2a,b patients was 94.4% at 5 years, 67.9% at 10 years, and 41.5% at 15 years. Survival for 92 Stage T3 patients was 87.3% at 5 years, 54% at 10 years, and 26.6% at 15 years. The survival for 85 any T,N1,M0 patients was 73.9% at 5 years, 34.4% at 10 years, and 8.5% at 15 years. At 15 years, 75.2% of Stage T1a,b patients, 41.5% of Stage T2a,b patients, 21.7% of Stage T3 patients, and 8.5% of Stage T,N1,M0 patients remained free of local recurrence and distant metastases. The elevation of prostatic acid phosphatase prior to radiotherapy was an unfavorable prognostic factor, with impact on both loco-regional recurrences and survival. CONCLUSIONS: The external beam radiotherapy for localized carcinoma of the prostate produced a good loco-regional control, NED, and overall survival. Patients with smaller tumors and low grade fared better than the ones with more aggressive and/or bulky tumors. The weakness of this study is the absence of serial prostate-specific measurements, which were not available during the period under study. The complication rate requiring surgical intervention was low, i.e. 0.4%.


Asunto(s)
Carcinoma/radioterapia , Neoplasias de la Próstata/radioterapia , Fosfatasa Ácida/sangre , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/mortalidad , Carcinoma/patología , Supervivencia sin Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Traumatismos por Radiación/complicaciones , Dosificación Radioterapéutica , Factores de Tiempo
18.
Pediatrics ; 90(1 Pt 1): 33-6, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1614775

RESUMEN

The relationship between bleeding and bruising and the production of prostacyclin and thromboxane was assessed in children who were to have a tonsillectomy and/or an adenoidectomy. Eicosanoids in the blood oozing from the bleeding time incision were measured and correlated with the reported frequency of bruising and epistaxis. A striking association (P = .0003) between prostacyclin production and the frequency of bruising was found; children reporting bleeding at least biweekly had the highest prostacyclin synthesis. Successively lower levels of the prostacyclin metabolite, 6-keto-prostaglandin F1 alpha, were found in children reporting less frequent bruising. Prostacyclin production in bleeding time blood was also correlated inversely with systolic blood pressure and hemoglobin level, although neither of these variables could explain the association between prostacyclin production and bruising. There was no correlation between thromboxane formation, systolic blood pressure, hemoglobin level, age, or bleeding time and the frequency of bruising. The ratio of thromboxane B2 to 6-keto-prostaglandin F1 alpha was correlated inversely with the length of the bleeding time (P = .016). It is concluded that vascular prostacyclin production may have a role in bruising symptomatology. It is suggested that prostacyclin formed at the injured vessel surface collects within the first few seconds after injury inside the tissue space at the site of the bruise and, by influencing the formation of the platelet/fibrin plug and/or the leakage of blood from the vessels, plays a significant role in modifying the development of bruising.


Asunto(s)
6-Cetoprostaglandina F1 alfa/sangre , Contusiones/sangre , Epoprostenol/biosíntesis , Tromboxano B2/sangre , Adolescente , Tiempo de Sangría , Recuento de Células Sanguíneas , Niño , Preescolar , Contusiones/metabolismo , Epoprostenol/metabolismo , Humanos , Factores Sexuales , Tromboxanos/biosíntesis , Tromboxanos/metabolismo
19.
Pediatrics ; 92(1): 128-34, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8390644

RESUMEN

BACKGROUND: Prolonged hospitalization of low birth weight infants increases the risk of medical and psychosocial complications. The feasibility of earlier discharge with community-based follow-up of infants of < or = 2000 g birth weight, without the use of home apnea monitors, was investigated. METHODS: One hundred infants of < or = 2000 g birth weight were randomized to either an intervention or control group. Intervention infants were discharged when readiness criteria were met. Based on assessed need, intervention group families received public health nursing and homemaker services for up to 8 weeks. Control infants were discharged to their homes at the discretion of the attending physician. All infants were assessed blindly at age 1 year with the Bayley and Home Observation for Measurement of the Environment (HOME) scales. RESULTS: There were no group differences in baseline infants' characteristics or in neonatal complications. Infants in the intervention group were discharged from the hospital at an earlier postconceptional age (mean +/- SD 36.6 +/- 1.5 weeks vs 37.3 +/- 1.6 weeks; P < .04). Median length of hospital stay (23 days vs 31.5 days) and mean weight at the time of discharge (2200 +/- 288 g vs 2275 +/- 301 g) were lower, but not significantly, for infants in the intervention group. A secondary analysis by birth weight strata (< or = 1500 g and 1501 through 2000 g) revealed that the most significant reductions in hospital stay and weight at discharge were realized in infants of 1501 through 2000 g birth weight. The persistence of apneic episodes and need for electronic monitoring prevented earlier discharge of infants of < or = 1500 g birth weight. Postdischarge services to the intervention group included 185 public health nurse home visits (3.8 +/- 0.91), 410 phone contacts (8.4 +/- 5), and 2298 homemaker hours (46 +/- 78) of service. At 1 year, there were no deaths and no group differences in rehospitalization rates, use of ambulatory services, or Bayley scores. Intervention families had significantly higher 1-year HOME scores. Minimum cost of hospital care was $873 per day, while the total cost of community-based services averaged $626 per infant. CONCLUSIONS: A significant reduction in average length of hospital stay was achieved for infants of 1501 through 2000 g birth weight. Earlier discharge of infants weighing < or = 1500 g at birth was hampered by persistent apneic episodes and feeding difficulties. A community-based program designed to provide individualized support and education for families of low birth weight infants was cost-effective and had a positive influence on the home environment.


Asunto(s)
Cuidados Posteriores , Servicios de Atención de Salud a Domicilio , Recién Nacido de Bajo Peso , Alta del Paciente , Cuidados Posteriores/economía , Análisis Costo-Beneficio , Estudios de Seguimiento , Servicios de Atención de Salud a Domicilio/economía , Servicios Domésticos/economía , Humanos , Lactante , Recién Nacido de Bajo Peso/crecimiento & desarrollo , Recién Nacido , Tiempo de Internación , Manitoba
20.
Thromb Haemost ; 65(3): 237-41, 1991 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-2048048

RESUMEN

A questionnaire, designed to assess bleeding/bruising tendencies, was administered to 251 otherwise healthy children undergoing a tonsillectomy and/or adenoidectomy. 23 children with excessive bleeding during or after the operation, with a long bleeding time or who reported taking aspirin recently were excluded, to give a population of 228 non-bleeders. For comparative purposes, 31 patients with bleeding disorders (von Willebrand's disease and/or platelet function defects) were studied. A considerable proportion of "non-bleeding" children reported easy bruising (24%), had bruises at least once a week (36%) and suffered from nosebleeds (39%). The respective frequencies (67%, 68% and 69%) for children with bleeding disorders were significantly higher. Occurrence of bruises usually on more than one part of the body, frequent large bruises or hematomas were rare in "non-bleeders" (4.9%, 3.5% and 2.7% respectively), but more common in "bleeders" (38.5%, 29.6% and 21.7% respectively).


Asunto(s)
Hemorragia/epidemiología , Adenoidectomía/efectos adversos , Adolescente , Trastornos de la Coagulación Sanguínea/complicaciones , Niño , Preescolar , Femenino , Hemorragia/etiología , Humanos , Masculino , Estudios Prospectivos , Encuestas y Cuestionarios , Tonsilectomía/efectos adversos
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