Molecular Classification of Breast Carcinoma in a Tertiary Hospital of India: the Recent Trends

Breast cancer is a heterogeneous disorder with various subcategories of different cellular compositions, molecular alterations, and clinical behaviour and is dependent on numerous factors like grade, size, and hormonal receptors which influence the overall prognosis and response to the treatment. This study was done to determine the frequency of estrogen receptor (ER), progesterone receptor (PR), and Her2 neu positivity in breast cancer patients, further classifying them into their molecular types (luminal A, B, Her2 neu, and triple-negative) and studying their association with histological subtypes, lymph node status, and other epidemiological parameters. This was a 5-year retrospective study done on 314 patients. All relevant clinical data including the age, sex, and lymph node status along with the histological type and grade of the tumour were recorded, and immunohistochemical evaluation of Her2 neu, ER, and PR receptors was done. The results showed that ER was the most predominant immunomarker, followed by PR, with an inverse relationship between ER, PR, and Her2 neu. Among the molecular subtypes, luminal B showed the maximum prevalence followed by triple-negative and Her2 neu subtype. The least frequency was shown by luminal A. Our study concluded that molecular subtyping of breast carcinoma plays an important role in determining the prognosis, recurrence, and treatment. Increased expression of luminal B subtype can be correlated due to the advancing age of the patients.