8505 Background: Yoga, an ancient Indian science, incorporates stress-reduction techniques that include regulated breathing, visual imagery, and meditation, as well as various postures that may be useful for cancer patients. Methods: A yoga program was developed that including loosening and breathing exercises, postures, alternate nostril breathing, a deep relaxation technique, and meditation for patients with breast cancer who were undergoing radiotherapy. Women participated in bi-weekly classes during their 6 weeks of radiation treatment. Sixty-one women with breast cancer were randomly assigned to either the yoga program or to a waitlist control group. Patients completed measures of intrusive thoughts and avoidance behaviors (Impact of Events Scale: IES), depressive symptoms (CES-D), sleep disturbances (Pittsburgh Sleep Quality Index), fatigue (BFI), and quality of life (SF-36) at baseline, 1 week, and 1 and 3 months after the last radiation therapy. We report on the outcomes 1 week after the end of radiotherapy. Results: The average age of the women was 52, 3% stage 0, 28% stage I, 43% stage II, and 26% stage III, 48% had undergone breast-conserving surgery, and 75% had received chemotherapy prior to starting radiotherapy. Analysis of covariance, controlling for baseline, revealed that the yoga group had significantly better SF-36 physical function scores (adjusted means: yoga 81.8 vs. control 68.6, P < 0.01), significantly higher SF-36 general health scores (adjusted means: yoga 78.3 vs. control 67.9, P < 0.03), marginally better SF-36 social functioning scores (adjusted means: yoga 85.3 vs. control 76.0, P > 0.1), significantly lower levels of sleep-related daytime dysfunction (adjusted means: yoga 0.5 vs. control 1.2, P < 0.04), and marginally lower levels of fatigue (adjusted means: yoga 1.9 vs. control 3.1, P < 0.06) than the control group. There were no other group differences on the SF-36 subscales or for the CES-D or IES scores. Conclusions: The results indicated that the yoga program was associated with statistically and clinical significant improvements in aspects of quality of life. No significant financial relationships to disclose.