Gables, FL. Hormonal treatment (HT) for advanced prostate cancer (APC) often results in side effects that can compromise quality of life (QOL). Limited work has evaluated the efficacy of psychosocial interventions among men undergoing treatment for APC. The current study evaluated the effects of a 10-week telephone-delivered and group-based Cognitive Behavioral Stress Management (CBSM) intervention on coping strategies, QOL and cortisol regulation among APC survivors undergoing HT. CBSM strategies included stress awareness, relaxation training, cognitive restructuring, and enhancing coping, social support and communication skills with an emphasis on managing treatment-related compromises in QOL. The HP condition involved delivery of health promotion information (e.g., benefits of proper diet, physical activity) with no therapeutic or interactive component. Participants (N=83) were randomized to either CBSM or a health promotion (HP) control condition and were assessed at two time points (T1; baseline, and T2; about 12 weeks post-randomization into the CBSM or HP conditions). The mean age was 70.0 years (SD=9.5) and the sample was ethnically diverse (66% White, 18% Black, 12% Hispanic, 4% Other). Participants had undergone an average of 19.1 months (SD=17.4) of HT. Measures included the Expanded PC Index Composite (EPIC) for treatment-related symptoms and QOL; the COPE Inventory (COPE); Measure of Current Status (MOCS) for perceived stress management skills and salivary cortisol. Analyses were conducted using repeated-measures group by time ANOVAs, controlling for relevant covariates. Participation in the CBSM intervention condition, relative to the HP control condition, was associated with improvements in disease-specific (i.e., urinary and bowel function) and general QOL, adaptive coping strategies, stress management skills and cortisol regulation (all p's<.05). Several mediation models were tested where coping and other stress management strategies were hypothesized to mediate the relationship between group condition and QOL. Both greater acceptance (p<.05) and less denial (p<.01) coping were found to be significant mediators of intervention-related improvements in QOL but did not mediate the effect of the intervention on cortisol regulation. These results suggest that participation in a telephone based CBSM intervention may be effective in improving general and disease-specific QOL, stress management skills and cortisol regulation. over time (p<.0001). Prostate cancer patients had significantly lower levels of anxiety, insomnia, fatigue and pain (ps<.001 or less) compared to patients with other types of cancer, but no significant differences were found across cancer stages over time. Patients having received chemotherapy were those displaying the greatest levels of insomnia and fatigue (ps<.05 or less), whereas patients treated by surgery only (no radiation or hormone therapy, or chemotherapy) were those displaying the lowest levels of anxiety and insomnia (ps<.001 or less) over time. In summary, cancer patients reported an overall decrease in depression, anxiety and insomnia symptoms, stable fatigue and an increase in pain over the 18-month period following surgery. Results also revealed some differences across cancer sites and treatment regimens received. Further longitudinal studies are needed in order to identify additional factors associated with changes in cancer-related symptoms over time.