Clinicopathological Profile of Triple Negative Breast Cancer: A Cross-sectional Study

Introduction: Triple Negative Breast Cancer (TNBC) is a subtype of breast cancer, characterised by the lack of expression of Oestrogen Receptor (ER) Progesterone Receptor (PR) and Human Epidermal growth factor Receptor (HER2). TNBC is an aggressive type of invasive breast cancer. The clinical, histopathology, and immunohistochemistry study are vital in diagnosing TNBCs. TNBC have rarely been studied in relation to rare prevalence, diagnostic difficulties, and special histological variants. Aim: To study the clinicopathological profile of TNBC pateints. Materials and Methods: The present cross-sectional study, which included all the patients undergoing lumpectomy or modified radical mastectomy received in the the Surgical Pathology Section of tertiary care hospital and department of molecular biology and genetic laboratory, at Krishna Institute of Medical Sciences, Karad, Maharashtra, India from May 2019 to April 2021. During the study period, total of 302 specimens of modified radical mastectomy or lumpectomy that met the inclusion/exclusion criteria were received in the Surgical Pathology department were included in this study. All specimens were analysed using immunohistochemistry for ER, PR, and HER2 Neu expression. Out of these, 100 (33.1%) cases were negative for all three markers, reported as TNBCs. These 100 TNBC cases were evaluated based on the clinicopathological parameters such as patient age, tumour laterality, location, tumour size, histopathological type, histologic Grade, lymphovascular invasion and lymph nodal status of TNBCs and to analyse different histomorphological type. Results: In this total of 302 specimens of modified radical mastectomy, the Invasive Breast Carcinoma No Special Type (IBC NST) (82.70%, 250 out of 302 specimens) was the commonest histopathological diagnosis, followed by medullary carcinoma seven cases (7.0%), metaplastic carcinoma two cases (2.0%), invasive lobular carcinoma two cases (2.0%), one case of apocrine carcinoma (1.0%), one case of neuroendocrine carcinoma (1.0%) and one case of each (1.0%) as malignant phyllode’s tumour, mucinous carcinoma, etc. Conclusion: Prevalence of TNBC in India is considerably higher compared with that seen in Western populations. Present study included extensive analysis of breast cancer showing increasing in incidence of TNBC and is challenging to treat due to its adverse clinicopathological profile. The TNBC is associated with younger age, larger tumour size, higher histopathological Grades, extensive tumour necrosis, more regional lymph node metastasis, advanced stage at diagnosis and aggressive nature of tumour.