Clinicopathological characteristics and prognosis of patients with breast invasive lobular carcinoma by different molecular subtypes / 肿瘤

ABSTRACT

Objective: To investigate the clinical features and the relationship between molecular subtypes and the clinical features and prognosis of invasive lobular carcinoma (ILC) of breast. Methods: The clinical records of 381 patients with resectable breast ILC in Tianjin Medical University Cancer Institute and Hospital were collected from January 1, 2003 to December 31, 2012. Based on the result of immunohistochemistry, four molecular subtypes were determined, including Luminal A, Luminal B, human epidermal growth factor receptor 2 (HER2) over-expression and triple-negative breast cancer (TNBC). The correlations of the prognosis in patients with different breast cancer molecular subtypes and the clinicopathological characteristics were analyzed. Results: The proportions of the four molecular subtypes were different; Luminal B accounted for the highest proportion (66.4%) and the proportions of Luminal A, HER2 over-expression and TNBC were 16.8%, 5.5% and 11.3%, respectively. There were statistical differences among different molecular subtypes of breast ILC regarding the age, menopausal status and lymph node metastasis (all P<0.05). The univariate analysis showed that factors affecting the prognosis of breast ILC were tumor size, axillary lymph node metastasis, clinical stage, molecular subtypes, surgical method, post-operative radiotherapy and endocrine therapy (all P<0.05). The 5-year overall survival rates of patients with Luminal A and Luminal B subtypes were 100.0% and 91.2%, respectively, which were significantly higher than those of the HER2 over-expression and TNBC subtypes (55.6% and 50.9%, respectively). Multivariate analysis found that the tumor size, molecular subtypes, axillary lymph node metastasis and endocrine therapy were the independent prognostic factors of breast ILC (all P<0.05). Conclusion: Molecular subtype classification has great significance in predicting the prognosis of breast ILC. Further studies are needed to guide the individual treatment of breast ILC.