Characteristics and outcomes of patients with multifocal/multicentric and unifocal breast cancer.

Purpose: The clinical behavior and outcome of multifocal (MF) and multicentric (MC) breast tumors are not well characterized. The purpose of this study was to compare the prognosis of MF/MC tumors with unifocal (UF)tumors and its correlation with other pathological characteristics and patient outcomes.
Methods: Eighty-three patients with MC/MF breast cancer and 501 with UF breast cancer treated at the Surgical Clinic Nis were studied. We compared MC/MF and UF breast cancer patients with respect to demographics, tumor characteristics- adjuvant systemic therapy, local recurrence-free survival (LRFS) and overall survival (OS).
Results: There was no significant statistical difference between the two groups with respect to mean age at diagnosis, tumor grade, nodal status, estrogen receptor status, lymphovascular invasion (LVI) and adjuvant systemic therapy. The MC/MF group had more patients with modified radical mastectomy and the UF group had more patients with breast-conserving surgery. Cox multivariate regression analysis showed that the regional lymph node metastases and LVI were the most important predictors of 5-year OS rate. During this period, locoregional recurrence was registered in 29 (5.78%) patients in the UF group and in 5 (6.02%) patients in the MF/MC group (p=0.48). No statistically significant differences in the 5-year LRFS and OS between the two groups were noticed.
Conclusion: The prognostic value of MF/MC disease is still not well known, although some studies have suggested that it is associated with a worse prognosis. This study showed no statistically significant difference in the 5-year LRFS and OS between UF and MF/MC groups.