Effects of hormone receptor status on patient clinic and survival in HER2 positive breast cancer.

Background: In the current study, the effect of hormone receptor (HR) status on clinical and survival in early-stage human epidermal growth factor receptor 2 (HER2)-positive breast cancer was investigated.

Methods: Two hundred ninety-one patients with HER2- positive were examined in two categories as HR-positive and HR-negative.

Results: Of these, 197 (68%) were HR-positive and 94 (32%) were HR-negative with a mean follow-up period of 68 ± 2.7 months. The groups were found to be similar in terms of age, menopausal status, comorbidity, pathologic type, stage, T stage, N stage, lymphovascular invasion, presence and percentage of intraductal component, multicentricity/focality and extracapsular invasion. Family history (P = 0.038), stage 2 tumor rate (P < 0.001), and perineural invasion (P = 0.005) were significantly higher in the HR-positive group. In the HR-negative group, mean Ki-67 value (P = 0.014), stage 3 tumor rate (P < 0.001), tumor necrosis (P = 0.004) and strong (3+) HER2 staining on immunohistochemical staining (P = 0.003) were higher. The incidence of relapse and metastasis, and the localization of metastasis were similar in both patient groups. The rate of locoregional relapse during the first 2 years was higher in the HR-negative patients than in the HR-positive patients (P = 0.023). Overall survival (OS) and disease-free survival (DFS) did not differ between the groups in univariate analysis. However, HR status was determined as an independent prognostic factor (HR: 2.11, 95% CI: 1.17-3.79; P = 0.012) for OS was not found to be significant for DFS in multivariate analysis.

Conclusion: Both clinicopathologic features and OS outcomes of HR-negative patients were worse than those of HR-positive patients.