Breast cancer: the dilemma of local recurrence

Local recurrence following surgery for breast cancer has long been considered a grave sign. Recent controlled trials indicate that breast and axillary recurrences can behave in an innocent fashion and, in many cases, contribute no risk to patient survival. Thus far there is no biological explanation for the remarkable finding. It is suggested here that patients vary widely in their defense against metastasizing tumor cells, and that the level of resistance is quite stable throughout one's life. Natural killer (NK) cells may contribute significantly to this role of immune protection. From these two assumptions an hypothesis is fashioned which attempts to reconcile the different perceptions of locally recurrent breast cancer.