The aim of this study was to investigate whether multifocality (MF) is a factor that has significant effect on overall survival when controlling for known prognostic factors. A cohort of 929 breast cancer patients operated between 1985 and 1990 was investigated. Of these, 158 (17%) patients had MF tumors and 771 had unifocal tumors. To investigate whether MF is an independent prognostic factor for overall survival in breast cancer, a Cox regression model was applied. Only tumor size, positive lymph nodes, histologic grade and receptor status had a significant effect on overall survival in the multivariate analysis. We found a positive correlation between tumor size and MF and between the number of positive lymph nodes and MF. In conclusion, MF had no significant effect on overall survival besides that which can be explained by other prognostic factors.
Copyright 2003 Elsevier Ltd.