ABSTRACT
Observations from Clinicopathological Studies It is frequently reported that the majority of breast cancer relapses occur within the vicinity of the original tumor bed. In reality, there are confl icting data regarding the spatial pattern of ipsilateral breast tumor relapse, which does not always correspond closely to pathological fi ndings. This observation is
reviewed in detail by Mannino and Yarnold and is summarized here (1). Five prospective RCTs of breast conservation surgery with or without whole-breast radiotherapy, have reported a 76-90% “same site” spatial pattern of relapse (2-6). In contrast, the European Organization for Research and Treatment of Cancer (EORTC) boost versus no-boost trial reported a 42% rate of relapse outside the original tumor area following a median follow-up of more than 10 years (7). This discrepancy in the spatial pattern of recurrence within RCTs could possibly be explained by differences in the defi nition of “same site” relapse. For example, the EORTC reported these relapses as within the tumor bed or scar, whereas other studies used different defi nitions such as the index quadrant or some arbitrary distance from the tumor bed/scar.
