This quasi-prospective study of 2163 women attending a breast-screening clinic for a routine medical check-up indicates that certain types of coping strategies and personality dispositions predispose some women to an increased risk of developing breast cancer following the occurrence of a major life-event such as bereavement or other loss-related event. Regular exposure to stress situations appears to reduce the risk of a malignancy; experiencing a single, major life event was found to be potentially much more damaging, particularly if the individual was unable to externalize her emotions and obtain appropriate help and counselling.