Cancer-related beliefs and health behavior change among breast cancer survivors and their first-degree relatives.

It is unclear why some cancer survivors and their relatives are motivated by the (personal or vicarious) cancer experience to make positive health behavior changes while others are not. Consistent with Leventhal's Commonsense Model, we hypothesized that breast cancer survivors and their first-degree relatives (FDRs) would change behaviors they believed: (1) had caused the survivor's cancer or (2) could prevent a future cancer incidence. Sixty-five breast cancer survivors (stages 0-III) and 33 FDRs were recruited. Assessments occurred within three months of the survivor completing treatment (i.e. all surgery, chemotherapy, and radiation) and again three months later. Findings indicate that survivors who believed that unhealthy diet, insufficient exercise, or alcohol consumption contributed to their cancer were more likely to modify the relevant behavior. Likewise, survivors were more likely to implement healthy changes they believed would ward off a recurrence. Findings were similar when data from FDRs was added to the sample. Thus, healthy lifestyle changes after a personal (and possibly a vicarious) cancer diagnosis are tied to whether individuals believe changes can affect cancer outcomes. Given the role of health behavior change in reducing medical risks, these findings have important implications for maintaining the health of cancer survivors.