Cortisol levels and responses to mammography screening in breast cancer survivors: a pilot study.

OBJECTIVE: The purpose of this study was to compare baseline levels of salivary cortisol, diurnal cortisol slopes, and cortisol reactivity to a mammogram in breast cancer survivors and women without a history of cancer.
METHODS: Participants were 33 breast cancer survivors (3-5 years postdiagnosis) and 21 women with no history of cancer who were scheduled for a routine follow-up mammogram. The first assessment occurred for 3 consecutive days 1 month before the mammogram, and the second assessment occurred on the day before, the day of, and the day after the mammogram. On each of these days, women completed questionnaires and collected saliva samples 6 times/day.
RESULTS: Results indicated that breast cancer survivors had higher levels of cortisol at baseline than controls. There were no group differences in diurnal slopes in cortisol concentration or cortisol responses to wakening. There were group differences in cortisol responses to the mammogram: In breast cancer survivors, cortisol levels decreased from the 3-day baseline period to the 3-day period around the mammogram, whereas in the control subjects mean daily cortisol levels increased around the mammogram. Among cancer survivors, there were no significant associations between cortisol measures and general stress ratings, although there were some associations with specific psychological responses to mammography.
CONCLUSIONS: Results of this pilot study indicate that breast cancer survivors show elevated levels of basal cortisol and suppressed cortisol response to a cancer-related stressor several years after completing treatment. Future research is needed to understand whether these patterns of hypothalamic-pituitary-adrenal functioning are a result of physiologic stress associated with cancer treatment or disease process, psychological stress associated with fear of recurrence, or a combination of both.