Aim: To determine the impact of biological subtypes defined by hormonal receptors and human epidermal growth factor receptor-2 status on risk of recurrence in women with invasive breast cancer treated with breast-conserving therapy.
Patients and methods: Between 2001-2005, we observed 590 women with invasive breast cancer. They underwent conservative surgery, adjuvant radiotherapy and hormonotherapy or chemotherapy. None received adjuvant trastuzumab. The Kaplan-Meier method was applied to calculate for the 36-month and 60-month rates of locoregional recurrence-free survival and overall survival.
Results: The overall 36- and 60-month actuarial Kaplan-Meier survival rates were 98.5% and 97.7%, respectively; the locoregional recurrence-free survival rates were 95.2% and 91.2%, respectively. Locoregional recurrence rate was significantly greater in patients with human epidermal growth factor receptor-2 (15.2% vs. 5.3%, p<0.001).
Conclusions: Patients with hormone receptor-negative or human epidermal growth factor receptor-2-positive T1-T2 breast cancer seem to have a greater risk of disease recurrence.
Keywords: HER2; breast cancer; locoregional recurrence; radiotherapy.