[Triple negative breast cancer: clinical, pathological and molecular characteristics]

Triple-negative breast cancer (TNBC) is a very heterogeneous disease and refers to a subgroup of breast cancer. The purpose of this study was to describe the clinical, pathological and molecular features of TNBC. We conducted a retrospective analysis of 56 cases of TNBC diagnosed in the Department of Pathology at the Farhat Hached University Hospital over a period of three years (2018-2020). The incidence of TNBC was 5.62% and the mean age of the patients was 50.36 years. The most frequent reason for consultation was the discovery of breast nodules (98.21%). The diagnosis of TNBC was confirmed in 24 cases (42.86%) based on the analysis of mastectomy specimens. Invasive carcinoma of no special type (NST) was the most common histological type (47 cases; 82.5%). Mean tumor size was 35.5 mm. SBR grading was only specified in 42 cases (73.68%). Grade III was the most predominant type (78.6%, n = 33). The notion of lymph node metastasis was found in 44 reports and lymph node invasion was reported in 19 patients (43.2%). Immunohistochemical study showed that all patients were hormone receptor-negative (RO and RP) with no Her2 overexpression (n = 56; 100). This study results are generally in agreement with literature data. Despite recent molecular classifications, there is no clinically verified diagnostic test allowing for clear therapeutic standardization.