Clinical Outcomes of Adjuvant Hormone Therapy in a Cohort of Patients With Infiltrating Non-metastatic Breast Cancer in a Latin American Cancer Center.

INTRODUCTION: Breast cancer (BC) is the most commonly diagnosed cancer in women. This study evaluated the clinical outcomes and prognostic factors associated with disease-free survival (DFS) and overall survival (OS) in a cohort of patients diagnosed with hormone receptor-positive non-metastatic BC managed with adjuvant hormone therapy. METHODS: An observational, analytical, historical cohort study was conducted. DFS and OS rates were estimated, Kaplan-Meier survival functions were calculated, and Cox models were developed to assess the association between time to event (all-cause mortality or relapse) and hormone therapy exposure with a set of established variables. RESULTS: Inclusion criteria were met by 685 patients; the mean age at diagnosis was 58 years (SD=11.9 years). The most commonly used drug was tamoxifen for five years in 241 (35.7%) patients; 470 (69.6%) patients received initial therapy, 112 (16.5%) underwent switch therapy, and 93 (13.8%) had extended therapy. The factors associated with better rates of DFS and OS were early clinical stage (p=0.00), luminal A and luminal B Her2-positive biological subtypes (p=0.00), and adherence to adjuvant hormone therapy (p=0.001). Mortality rate was 0.77 deaths per 100 patients/year (95% CI, 0.51-1.2). CONCLUSION: This cohort demonstrated that adjuvant hormone therapy improves DFS and OS rates in locally advanced tumors. The main factor for reducing disease progression in this cohort was adequate adherence to treatment.

Factors Associated with Time to Progression and Overall Survival in Patients with De Novo Metastatic Breast Cancer: A Colombian Cohort.

PURPOSE: About 10% of breast cancer (BC) is diagnosed in stage IV. This study sought to identify factors associated with time to progression (TTP) and overall survival (OS) in a cohort of patients diagnosed with de novo metastatic breast cancer (MBC), from a single cancer center in Colombia, given that information on this aspect is limited. METHODOLOGY: An observational, analytical, and retrospective cohort study was carried out. Time to progression and OS rates were estimated using the Kaplan-Meier survival functions. Cox models were developed to assess association between time to progression and time to death, using a group of fixed variables. RESULTS: Overall, 175 patients were included in the study; 33.7% of patients had luminal B HER2-negative tumors, 49.7% had bone involvement, and 83.4% had multiple metastatic sites. Tumor biology and primary tumor surgery were the variables associated with TTP and OS. Patients with luminal A tumors had the lowest progression and mortality rates (10 per 100 patients/year (95% CI: 5.0-20.0) and 12.6 per 100 patients/year (95% CI: 6.9-22.7), respectively), and patients with triple-negative tumors had the highest progression and mortality rates (40 per 100 patients/year (95% CI: 23.2-68.8) and 44.1 per 100 patients/year (95% CI: 28.1-69.1), respectively). Across the cohort, the median TTP was 2.1 years (95% CI: 1.6; the upper limit cannot be reached) and the median OS was 2.4 years (95% CI: 2-4.3). CONCLUSIONS: In this cohort, patients with luminal A tumors and those who underwent tumor surgery given that they presented clinical benefit (CB) after initial systemic treatment, had the lowest progression and mortality rates. Overall, OS was inferior to other series due to high tumor burden and difficulties in accessing and continuing oncological treatments.

When is Sentinel Lymph Node Biopsy Useful in Ductal Carcinoma In Situ? The Experience at a Latin American Cancer Center.

Introduction Ductal carcinoma in situ (DCIS) accounts for 15% of breast cancers. Surgery is the main treatment, and the use of sentinel node biopsy (SLNB) is restricted to patients at risk of infiltration, which is estimated to be around 26%. Materials and methods Aimed at evaluating the benefit of SLNB in patients with DCIS at the Breast and Soft Tissue Functional Unit of the National Cancer Institute (INC for its initials in Spanish), a descriptive observational study of a retrospective cases series was conducted between August 1, 2013, and September 30, 2018. Results A total of 40 patients with a median age of 57 years were included in the study; 62.5% of them underwent mastectomy with SLNB, and the remaining 37.5% underwent conservative surgery with SLNB. 100% of sentinel nodes were identified, by using lymphoscintigraphy in 95%. Sentinel node was positive in four patients (10%), three of whom had infiltration in the surgical specimen reported. With a follow-up of 49 months, only one patient had a local relapse. None of the patients had axillary or distant recurrence. Conclusions SLNB in DCIS should be limited to patients with risk factors for infiltration (tumor size greater than 3 cm, comedo-type histology, and high-grade DCIS), and patients with an indication for mastectomy. Its percentage of complications is low, and a high identification percentage in surgical groups with adequate training.

Evaluation of the AJCC Eighth-Edition Prognostic Staging System for Breast Cancer in a Latin American Cohort.

BACKGROUND: The staging of breast cancer has been based on tumor size, lymph node involvement, and presence or absence of distant metastases. The American Joint Committee on Cancer (AJCC) staging system in its eighth edition incorporates hormone receptors, human epidermal growth factor receptor 2 (HER2), and histologic grade due to their prognostic importance. In Latin America, however, the impact of the new edition is unknown. This article evaluates the performance of the AJCC eighth-edition staging system in a cohort of patients with breast cancer at a reference center in Colombia. METHODS: The study investigated a descriptive cohort of 912 patients who received complete treatment for non-metastatic invasive breast cancer and had information on the anatomic stage and biologic factors,. All the patients were restaged using the AJCC eighth-edition classification. Changes in clinical stages and differences between the two classifications were compared. RESULTS: The study enrolled 912 patients. Changes in staging occurred for 54.82% (downstaging for 40.3% and upstaging for 14.47%) of these patients. For recurrence-free survival, the C-Index of the eighth-edition AJCC was 0.726, and the AIC was 1323.7, whereas the C-Index of the seventh-edition AJCC was 0.731, and the AIC was 1314.3 (p = 0.99). CONCLUSIONS: The seventh and eighth editions of the AJCC staging system have similar predictive values in our population for recurrence-free survival. Future studies are necessary to evaluate the performance of the AJCC eighth-edition staging system in predicting overall survival.

Breast Sarcomas: Experience of a Reference Center in Colombia.

Introduction  Breast sarcomas are tumors of a mesenchymal origin, with an incidence of less than 1% of the total breast tumors. The diagnosis of this disease is a challenge for pathologists, radiologists, and breast surgeons.  Aim To describe the diagnostic, therapeutic, and outcomes approach of patients with breast sarcoma treated at the National Cancer Institute (NCI) in Bogota, Colombia.  Materials and methods It is a descriptive and retrospective case series study of patients diagnosed with breast sarcoma treated at the NCI during the period between August 1, 2016 and March 30, 2019.  Results  We identified 14 patients diagnosed with breast sarcoma, 10 (71.4%) patients with primary breast sarcomas, and four (28.6%) with sarcomas associated with radiotherapy. The most frequent histological subtype in both, primary and secondary sarcomas, was angiosarcoma (n = 5, 35.7%). 100% (n = 14) of patients received surgical management as primary treatment. Eight (57.1%) patients presented recurrence (disease-free survival (DFS) follow-up of 5.95 months). A total of five deaths were recorded, representing 35.7% of patients (overall survival (OS) follow-up of 23.5 months). Conclusion Breast sarcomas are characterized by aggressive clinical behavior, which is why it is important to make a precise histological diagnosis and thus provide patients with radical surgical procedures that ensure local control of the disease and improve DFS.

Pathological Response to Neoadjuvant Chemotherapy and the Molecular Classification of Locally Advanced Breast Cancer in a Latin American Cohort.

BACKGROUND: The majority of patients with breast cancer in Colombia are admitted into oncological centers at locally advanced stages of the disease (53.9%). The aim of this study was to describe the pathological response obtained with neoadjuvant chemotherapy (NACT) according to the molecular classification of breast cancer in patients with locally advanced tumors treated within the National Cancer Institute (NCI) Functional Breast Cancer Unit (FBCU) in Bogotá, Colombia. MATERIALS AND METHODS: This was an observational, descriptive, historical cohort study of patients with locally advanced breast cancer treated within the NCI FBCU. RESULTS: We included 414 patients who received NACT and surgical management. Most patients had luminal B HER2-negative tumors (n = 134, 32.4%). The overall rate of pathological complete response (pCR) ypT0/ypN0 was 15.2% (n = 63). Tumors that presented the highest rate of pCR were pure HER2, at 40.5% (n = 15; odds ratio [OR], 6.7); however, with a follow-up of 60 months, only the triple negative tumors presented a statistically significant difference for event-free survival (EFS; median recurrence time, 18 months; range, 1-46) and overall survival (OS; median follow-up, 31 months; range 10-57). The molecular subtype that most recurrences presented was luminal B HER2 negative, at 38.3% (n = 28). The majority of recurrences (93.2 %; n = 68; OR, 5.9) occurred in patients in whom no pathological response was obtained (Chevallier 3 and 4). CONCLUSION: Pathological response in locally advanced tumors is related to the molecular subtype of breast cancer, finding higher pCR rates in pure HER2 and triple-negative tumors. A direct relationship was found between disease recurrences and the pathological response, evidencing greater tumor recurrence in patients who did not respond to NACT (Chevallier 3 and 4). EFS and OS were greater in patients with pCR, with statistical significance only in triple-negative tumors. IMPLICATIONS FOR PRACTICE: This research article is of scientific interest, because it describes the clinical and pathological features and analyzes the correlation between pathological response to neoadjuvant chemotherapy and the molecular classification of locally advanced breast cancer in patients treated in the National Cancer Institute in Bogotá, Colombia. It was found that pathological response is related to the molecular subtype of breast cancer. In addition, there is a direct relationship between disease recurrences and pathological response. The survival results were greater in patients with pathological complete response.

Frecuencia de mutación y de variantes de secuencia para los genes BRCA1 y BRCA2 en una muestra de mujeres colombianas con sospecha de síndrome de cáncer de mama hereditario: serie de casos / Frequency of sequence mutations and variants for the BRCA1 and BRCA2 genes in a sample of Colombian women with suspected hereditary breast cancer syndrome: Case series

Describir variantes de secuencia en los genes BRCA1 y BRCA2 en una muestra de pacientes colombianas con historia personal o familiar de cáncer de mama sugestiva de riesgo genético.Materiales y métodos: serie de casos compuesta por 67 pacientes que fueron remitidas para estudio genético por sospecha de síndrome de cáncer de mama y ovario hereditario (HBOC). De los 67 casos, 42 (62,7 %) cumplieron con los criterios de indicación médica de la National Comprehensive Cancer Network (NCCN) del 2013, y en ellos se realizó secuenciación completa de los genes BRCA1 y BRCA2. Se determinó la frecuencia de mutación, variantes de secuencia y significancia clínica de las variantes halladas con base en Breast Cancer Information Core (BIC).Resultados: se identificaron mutaciones para el gen BRCA1 en seis pacientes (14,3 %), no se documentó mutación para el gen BRCA2, además se detectaron 43 variantes genéticas en 27 pacientes (64,2 % de 42 casos). De estas, 21 (48,8 %) fueron identificadas en el gen BRCA1 y 22 (51,2 %) en el gen BRCA2. Dentro de estas variantes, se identificaron 5 mutaciones patogénicas solo en el gen BRCA1, de las cuales solo una había sido reportada previamente en Colombia.Conclusiones: este estudio identifica variantes genéticas patogénicas en el gen BRCA1 no descritas en estudios previos en la población colombiana y otras conocidas en diferentes poblaciones; permitiendo de esta forma ampliar el conocimiento sobre las variantes en población colombiana de los genes BRCA1 y BRCA2. Sin embargo, se requieren más estudios con suficiente poder y calidad metodológica para poder estimar la frecuencia de mutaciones y de variantes de secuencia para estos genes en mujeres colombianas con sospecha de síndrome de cáncer de mama u ovario hereditario...

To describe sequence variants in the BRCA1 and BRCA2 genes in a sample of Colombian patients with a personal or family history of breast cancer suggestive of genetic risk.Materials and methods: Case series consisting of 67 patients referred for genetic testing because of suspected hereditary breast and ovarian cancer syndrome (HBOC). Of the 67 cases, 42 (62.7%) met the medical indication criteria of the 2013 National Comprehensive Cancer Network (NCCN) and they were subjected to the entire sequencing of the BRCA1 and BRCA2 genes. A determination was made of the frequency of sequence mutation, variants, and of the clinical significance of the variants found based on the Breast Cancer Information Core (BIC).Results: Mutations were identified for the BRCA 1 gene in six patients (14.3%), no mutation was documented for the BRCA 2 gene, and 43 genetic variants were found in 27 patients (64.2% of 42 cases). Of these, 21 (48.8%) were identified in the BRCA1 gene and 22 (51.2%) in the BRCA 2 gene. Among these variants, 5 pathogenic mutations were found only in the BRCA1 gene and, of those, only 1 had been reported previously in Colombia.Conclusions: This study identifies pathogenic genetic variants in the BRCA1 gene not described previously in the Colombian population, as well as others known in different populations. Therefore, it helps expand knowledge regarding the variants of the BRCA1 and BRCA2 genes in the Colombian population. However, additional studies are required with sufficient power and methodological quality to estimate the frequency of sequence mutations and variants for the BRCA1 and BRCA2 genes in Colombian women suspected of having the hereditary breast or ovarian cancer syndrome...