Immunohistochemistry-based molecular subtypes of breast cancer in Bosnian women: single-institution pilot study
Introduction: to evaluate the frequency and significance of immunohistochemistry-based molecular subtypes of breast cancer and investigate their association with traditional pathological features for breast cancer among Bosnian women. Materials and methods: this study included 100 female patients with primary invasive breast cancer. Immunohistochemical analyses for estrogen receptor (ER), progesterone receptor (PR), HER-2 and Ki-67 were performed to define four biological subtypes: luminal A, luminal B, HER-2-positive and triple-negative. Results: the frequency of luminal A, luminal B, HER2-positive and triple-negative subtypes of breast cancer was 44%, 39%, 11% and 6%, respectively. Molecular subtypes of breast cancer among Bosnian women showed to be independent of traditional pathological features (p>0.05). Ki-67 showed significant di erence regarding luminal B tumor type, where high (≥14%) Ki-67 score was predominantly represented in 36 (92.3%) cases (p<0.001). Conclusion: immunohistochemistry-based molecular subtypes of breast cancer in Bosnian women somehow vary in pathological features, i.e. luminal A subtype in this sample comprised mostly ductal histological type, moderate di erentiation with the involvement of lymph nodes, known as worse prognostic factors, although with no statistical significance.