Breast cancer is characterized by uncontrolled growth of malignant breast tissue cells and is a heterogeneous disease. The most common types are invasive ductal and lobular carcinoma. Annually, about 1,000,000 new cases arise worldwide, with an increasing prevalence in Asia. In Pakistan, approximately 51.7 out of 100,000 women are affected. This study investigates the association of the CASC16-rs4784227 polymorphism with breast cancer, analyzing both genetic and non-genetic risk factors. The study included 115 subjects (70 patients, 45 controls) from southern Punjab. Significant non-genetic factors included age, family history, menarche age, menopausal status, breastfeeding, BMI, and diet. Estrogen receptor (ER), progesterone receptor (PR), and HER2 status were also examined with 55.71% ER-positive, 62.86% PR-positive, and 54.29% HER2-negative cases. The most common cancer type was ductal carcinoma and stage 3 was the most prevalent. Tetra arms PCR was used for genotypic analysis which showed an association between SNP rs4784227-CASC16 and breast cancer in the Pakistani population.

Key words: Breast cancer, Invasive ductal carcinoma, Cancer- Susceptibility Candidate 16 gene (CASC16), Estrogen Receptor (ER), Progesterone Receptor (PR), Human Epidermal Growth Factor Receptor 2 (HER2)