Triple-negative breast cancer in India: Exploring age distribution and laterality patterns

Objectives: Breast cancer is a prevailing health concern globally, with India experiencing alarming rates. This study delves into the clinicopathological features of triple-negative breast cancer (TNBC), focusing on age distribution, laterality, tumor grade, and Ki-67 expression. Understanding these parameters is essential for tailoring effective therapeutic strategies for this aggressive subtype. Material and Methods: A retrospective analysis of 149 TNBC patients where human epidermal growth factor receptor 2 status was confirmed by fluorescent in situ hybridization as all the samples received are immunohistochemistry (IHC) equivocal. Clinical characteristics, including age, estrogen receptor/progesterone receptor status, Ki-67 expression, laterality, and histologic grade, were assessed through IHC. Statistical analyses, including Chi-square tests, were performed using the R language to discern differences between left and right breast cancers. Results: TNBC constituted 30.53% of 488 breast cancer cases, with a wide range reported in Indian studies. The median age was 55 years, and age distribution significantly associated with TNBC incidence ( P < 0.001). Left-sided TNBC predominated (69.12%), significantly influencing TNBC incidence ( P < 0.001). Tumor grade distribution showed no significant difference between left- and right-sided TNBC. Ki-67 expression was significantly associated with TNBC ( P < 0.001), with 96.24% exhibiting high expression (≥20%). Conclusion: This study provides a detailed analysis of TNBC clinicopathological characteristics, revealing significant associations in age distribution, laterality, and Ki-67 expression. The observed left-sided predominance and the association with Ki-67 underscore the need for vigilant monitoring and personalized treatment strategies in TNBC patients. The findings contribute to understanding TNBC heterogeneity, paving the way for tailored therapeutic approaches and emphasizing the importance of continued research in this complex disease.