Influence of breast cancer subtype on pathological complete response

ABSTRACT

Objective: To compare the rates of pathological complete response (pCR) after treatment with neoadjuvant chemotherapy, in the different subtypes of breast cancer in patients followed at the Mastology Service of Hospital do Servidor Público Estadual. Methods: Descriptive and retrospective study, in which medical records of 213 patients diagnosed with breast cancer and submitted to neoadjuvant chemotherapy were reviewed, from February 2011 through January 2018. Histological data collected were hormone receptors, hyperexpression of HER-2, grade, histological type and clinical data age of the patient at diagnosis, tumor size and clinical stage at diagnosis and after chemotherapy, and rate of pCR. Results: The mean age of patients at diagnosis was 53.97 years. Forty-six patients (21,6%) had pCR, 77 (36.1%) were grade 2 and 136 (63.9%) were grade 3. Regarding cancer subtype, 29 patients (13.6%) were reported to have pure HER2 subtype, 48 patients (22.5%) corresponded to Luminal A subtype, 51 (23.9%) to Luminal B, and 66 patients (31.0%) were characterized as Triple Negative, while only 17 patients (7.9%) had Luminal B HER. Conclusion: The subtypes Pure HER 2 and Luminal B had the highest pCR rates.