Genomic signatures in breast cancer in a real-world setting: Experience in a Brazilian Northeastern Center.

OBJECTIVE: We aim to evaluate the indication and use of genomic signatures in breast cancer patients and outcomes who in patients undergoing adjuvant chemotherapy or not. METHODS: This is a retrospective study of breast cancer patients managed in a private oncology clinic in Teresina, from November 2014 to February 2021. All patients with an indication of genomic signature were included. Clinical and pathological variables, use of genomic signatures, treatment and follow-up were obtained. The nomogram to predict Oncotype DX results (University of Tennessee Medical Center) was also calculated. Clinical risk calculation was based on MINDACT, using the modified version of Adjuvant Online. The genetic signatures performed were: the Oncotype, MammaPrint and EndoPredict. RESULTS: Fifty (50) female patients were included in the study. The mean age of the participants was 57.1 years. Among the patients receiving a genomic signature (26-52.0%), there was a change in treatment in 8 (30.7%) cases. Chemotherapy was indicated in four patients, It was contraindicated in another four patients. Treatment changed in 30.7% of the tested patients. Chemotherapy was indicated for those who would not receive it before. It was contraindicated in patients who would previously undergo chemotherapy.

Genetic testing for hereditary predisposition to breast cancer in the real world: Initial experience.

BACKGROUND: Around 5%-10% of breast cancers are due to hereditary breast and ovarian cancer syndrome. Genetic testing is important to identify these cases, enabling the adoption of specific risk-reducing treatment strategies. OBJECTIVE: To analyze the performance of genetic testing and its implications in patients with indication of genetic testing to identify hereditary predisposition to breast cancer. METHODS: This is a retrospective observational cross-sectional study, including 176 patients with clinical indication of genetic testing for pathogenic variants related to breast, ovarian and pancreatic cancers (among others), managed from 1999 to 2021 in an Oncology private clinic located in the city of Teresina (PI), Brazil. RESULTS: There was a predominance of female patients (98.9%) and those with a family (91.0%) and personal history (64.2%) of cancer. In the study, 102 patients (57.9%) received genetic testing. BRCA1 and BRCA2 pathogenic variants occurred in 26 cases (90%). Another three PALB2 and TP53 pathogenic variants were detected. Eleven pathogenic variant carriers (38%) underwent risk-reducing surgeries. CONCLUSIONS: BRCA1/BRCA2 pathogenic variants occurred in around 25% of tested patients. Approximately 42.0% of the patients did not undergo genetic testing, despite clinical indication.

Survival in metaplastic breast carcinoma: A case series.

BACKGROUND: Metaplastic breast carcinoma (MBC) is a rare type of breast cancer (0.20-1.00% of all cases). With a more aggressive clinical course, MBC frequently presents as a triple-negative subtype. OBJECTIVE: To describe a case series, analyzing patients survival in four MBC cases. METHODS: The cases were obtained from 532 medical records of breast cancer patients (0.7% of the total). RESULTS: All patients were female. Mean patient age was 49 years (range: 38-60 years). Mean tumor size was 8.9 cm (range: 3.0-15.5 cm). Mastectomy was performed in three cases. One patient had axillary nodal metastasis. All underwent chemotherapy and three received radiation therapy after surgery. CONCLUSIONS: With a mean follow-up of 36 months (range: 10-60 months), one case had a tumor recurrence (25%). Three patients (75%) died from metastatic disease and one (25%) is still alive and free of disease.