The Association between Molecular Subtypes of Breast Cancer with Histological Grade and Lymph Node Metastases in Indonesian Woman

Abstract

Objective: Breast carcinoma is a heterogeneous disease which is rich in diversity. Molecular subtypes of breast<br />cancer, histological grade and lymph node metastases are strong prognostic and predictive factors. In Indonesia,<br />only a limited number of studies have investigated the correlation between molecular subtypes with histological<br />grade and lymph node metastases. Methods: We analyzed 247 invasive breast carcinoma cases from the Anatomic<br />Pathology Installation of Dr. Sardjito General Hospital Yogyakarta between 2012-2015. The slides were stained for<br />estrogen receptors (ER), progesterone receptors (PR), HER2, Ki-67 and CK5/6 for classification into breast cancer<br />subtypes (BCS). Histological grade using the Nottingham system and lymph node status were obtained from anatomic<br />pathology records. The association between histological grade and lymph node status with BCS was examined with<br />Chi-square tests. Results: The immunohistochemical features of 247 cases of women with invasive breast carcinoma<br />were examined. There were 102 (41.3%) patients with Luminal A, 34 (13.8%) patients with Luminal B, 48 (19.4%)<br />patients with HER2-positive, and 63 (25.5%) patients with triple negative breast cancer (TNBC). There were 148<br />(59.9%) patients with negative lymph node status and 99 (40.1%) with positive status. Among 63 TNBC cases, 37<br />(58.7%) patients were positive for CK5/6 staining (basal-like). Statistically, there were significant differences between<br />histological grade and subtypes (p=0.013). However, no significant differences were found for lymph node metastases<br />(p=0.540). Conclusion: Among subtypes, Luminal A has the highest frequency, followed by TNBC, HER2-positive<br />and Luminal B. Histological grade was associated with molecular subtypes of breast carcinoma in Yogyakarta. Grade<br />I was associated with Luminal A, while Grade III was associated with Luminal B, HER2 and TNBC subtypes.