"NB: When staging such breast cancers, the convention is to report on the features of the largest tumour in terms of size and extension of the tumour."
"Multifocal breast cancer refers to two or more individual breast cancers diagnosed at the same time within the same quadrant of the same breast 1. There is, however, some heterogeneity in the way the term (as well as the term multicentric breast cancer) is used 4."