Objectives: Multifocal/multicentric breast cancers have been comprehensively studied and their outcomes have been compared with unifocal tumors. We evaluated the impact of multifocality and multicentricity on the disease-free survival (DFS) and overall survival of breast cancer patients and tried to analyze the correlation between multifocality/multicentricity (M/M) and other prognostic factors.
Material and methods: Between 1994 and 2009, we analyzed retrospectively 697 breast cancer patients. Multicentric and multifocal breast cancer were defined as the presence of 2 or more invasive tumor foci within the different quadrants of the same breast or within a same quadrant of the breast, respectively. M/M and other prognostic factors were evaluated using univariate and multivariate analyses.
Results: Multifocal/multicentric tumors were seen in 107 (15.4%) of the 697 breast cancer patients. pT and pN stage were related with the presence of multifocal/multicentric tumors. As tumor size increased and the number of axillary lymph nodes metastasis increased, the incidence of M/M increased significantly (P=0.003 vs. P=0.02, respectively). Overall, the median DFS time of patients with multifocal/multicentric tumors was significantly worse than that of the unifocal tumors (55 vs. 137 mo, P<0.001). Multivariate analysis showed that the presence of M/M was the most important prognostic factor for DFS (P=0.001, hazard ratio (HR): 0.33; 95% confidence interval (CI), 0.18-0.58), as were pN stage and extracapsular extension of the tumor (P=0.01, HR: 1.74; 95% CI, 1.13-2.69) (P=0.03, HR: 1.9; 95% CI, 1.04-3.47, respectively). M/M were not also statistically significant prognostic factors in breast cancer for overall survival (P=0.06).
Conclusions: M/M imparts an unfavorable prognosis on the DFS of breast cancer patients in comparison to unifocal tumors and the presence of multifocal/multicentric tumors were associated with advanced pT and pN stages.