True Local Recurrences after Breast Conserving Surgery have Poor Prognosis in Patients with Early Breast Cancer

Background: This study was aimed at investigating clinical and histopathologic features of ipsilateral breast tumor recurrences (IBTR) and their effects on survival after breast conservation therapy. Methods: 1,400 patients who were treated between 1998 and 2007 and had breast-conserving surgery (BCS) for early breast cancer (cT1-2/N0-1/M0) were evaluated. Demographic and pathologic parameters, radiologic data, treatment, and follow-up related features of the patients were recorded. Results: 53 patients (3.8%) had IBTR after BCS within a median follow-up of 70 months. The mean age was 45.7 years (range, 27-87 years), and 22 patients (41.5%) were younger than 40 years. 33 patients (62.3%) had true recurrence (TR) and 20 were classified as new primary (NP). The median time to recurrence was shorter in TR group than in NP group (37.0 (6-216) and 47.5 (11-192) months respectively; p = 0.338). Progesterone receptor positivity was significantly higher in the NP group (p = 0.005). The overall 5-year survival rate in the NP group (95.0%) was significantly higher than that of the TR group (74.7%, p < 0.033). Multivariate analysis showed that younger age (<40 years), large tumor size (>20 mm), high grade tumor and triple-negative molecular phenotype along with developing TR negatively affected overall survival (hazard ratios were 4.2 (CI 0.98-22.76), 4.6 (CI 1.07-13.03), 4.0 (CI 0.68-46.10), 6.5 (CI 0.03-0.68), and 6.5 (CI 0.02- 0.80) respectively, p < 0.05). Conclusions: Most of the local recurrences after BCS in our study were true recurrences, which resulted in a poorer outcome as compared to new primary tumors. Moreover, younger age (<40), large tumor size (>2 cm), high grade, triple negative phenotype, and having true recurrence were identified as independent prognostic factors with a negative impact on overall survival in this dataset of patients with recurrent breast cancer. In conjunction with a more intensive follow-up program, the role of adjuvant therapy strategies should be explored further in young patients with large and high-risk tumors to reduce the risk of TR.