histopathological characteristics of triple-negative breast cancer: an iranian issue

background : breast cancer is one of the most frequent malignancies among iranian women. triple-negative breast cancer (tnbc) is referred to a type of breast cancer which three biomarkers of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (her2), are negative. materials and methods: in this case control study, immunohistopathologic data of patients with tnbc were compared with non-tnbc patients. according to pathological reports, frequency, age, gender, type, size, and tumor grade, involvement and the number of involved lymph nodes, mitosis, ki-67, necrosis, nuclear grade, tumor side, involvement of the margins, skin involvement, nipple involvement, tumor location, vascular invasion, perineural invasion, presence of in-situ compartment and the benign accompanied tumors, granulomatosis reaction, and calcification were compared between both groups. results: two hundred fourteen pathological samples of patients with breast cancer were evaluated. tnbc was seen in about 14% of breast cancers in this study on iranian population. the mean age of tnbc group was 43±12 years and non-tnbc was 50±12 years (p=0.03). tnbc had significantly higher grade, high mitotic indices, more possibility of p53 positivity and higher level of ki-67. presence of vascular and nerve invasion and involvement of the margins at the time of diagnosis were seen in the tnbc group comparing with the non-tnbc group. conclusion: younger age, higher grading, neurovascular invasion, p53 positivity, and high levels of ki-67, lead clinicians to evaluate the biomarkers of tnbc, and in case of confirming tnbc diagnosis, appropriate treatment methods should be added to the routine ones in breast cancer.