Clinicopathological and Receptor Defined Subtype Landscape of Breast Cancer in an Institutional Cohort

Breast cancer is a heterogeneous malignancy in which integrated clinicopathological assessment and receptor-based classification are essential for prognostic evaluation and treatment planning. This retrospective descriptive study evaluated the clinicopathological characteristics and hormone receptor/HER2-defined subtype distribution of 75 histologically confirmed breast cancer cases from an institutional cohort. Data on age, tumor site, breast laterality, histological type, histological grade, T stage, N stage, AJCC stage, ER/PR status, HER2 status, HER2-low status, and combined receptor-defined subtype were extracted from clinical, histopathological, and immunohistochemistry records and summarized using frequencies and percentages. Most patients were aged >46 years (43/75, 57.0%), followed by 36-45 years (26/75, 35.0%) and <35 years (6/75, 8.0%). The upper outer quadrant was the most frequent tumor site (30/75, 40.0%), and right breast involvement was slightly more common than left-sided disease (43/75, 57.0% vs. 32/75, 42.66%). Invasive ductal carcinoma was the predominant histological type (70/75, 93.33%). Grade II tumors were most frequent (46/75, 61.33%), followed by grade III tumors (25/75, 33.33%). T2 was the dominant T stage (49/75, 65.0%), while N1 was the most common nodal stage (30/75, 40.0%). According to AJCC staging, stage IIB was the most frequent individual stage (19/75, 25.33%), followed by IIA (16/75, 21.33%) and IIIA (15/75, 20.0%). ER−/PR− tumors represented the largest ER/PR category (31/75, 41.33%), whereas HER2-negative disease was predominant (51/75, 68.0%). Overall subtype analysis showed that triple-negative breast cancer was the most frequent receptor-defined subtype (28/75, 37.33%), followed by HR+/HER2− disease (23/75, 30.66%) and HR+/HER2+ disease (9/75, 12.0%); HER2-low tumors were uncommon (2/75, 2.66%). These findings indicate that the cohort was characterized by predominance of invasive ductal carcinoma, intermediate-to-high histological grade, T2 disease, frequent nodal involvement, and a substantial burden of TNBC and HR+/HER2− tumors, underscoring the importance of complete histopathological staging and standardized receptor profiling for subtype-aware breast cancer assessment in institutional settings.