Multifocality and multicentricity in breast cancer and survival outcomes

The clinicopathological characteristics and the prognostic significance of multifocal (MF) and multicentric (MC) breast cancers are not well established. MF and MC were defined as more than one lesion in the same quadrant or in separate quadrants, respectively. The Kaplan–Meier product limit was used to calculate recurrence-free survival (RFS), breast cancer-specific survival (BCSS), and overall survival (OS). Cox proportional hazards models were fit to determine independent associations of MF/MC disease with survival outcomes. Of 3924 patients, 942 (24%) had MF (n = 695) or MC (n = 247) disease. MF/MC disease was associated with higher T stages (T2: 26% versus 21.6%; T3: 7.4% versus 2.3%, P