Purpose: Cognitive behavioral stress management (CBSM) is an empirically-validated group-based psychosocial intervention. CBSM is related to decreased self-reported indicators of psychological adversity during breast cancer treatment and greater disease-free survival (DFS) vs. a control condition. This study examined relationships between CBSM, DFS, and a potential biobehavioral pathway linking these variables in breast cancer patients through a gene expression composite representing the leukocyte conserved transcriptional response to adversity (CTRA). Design: Women with stage 0-IIIb breast cancer completed questionnaires and provided blood samples post-surgery. Participants were randomized to 10-week group-based CBSM or a psychoeducation control group and followed at 6 months, 12 months, and median 11 years. In total, 51 participants provided blood data for longitudinal analyses (CBSM n = 28; Control n = 23). Mixed model analyses examined CBSM effects on 6-12 month changes in CTRA expression (53 indicator genes representing pro-inflammatory, anti-viral and antibody production signaling). Cox regression models assessed the relationship between 6 and 12 month changes in CTRA expression and 11-year DFS. Results: Patients randomized to CBSM showed attenuated 6-12 month change in CTRA gene expression, whereas patients randomized to control showed increased CTRA expression (p = 0.014). Average DFS was 5.92 years (SD= 3.90). Greater 6-12 month CTRA increases predicted shorter 11-year DFS controlling for covariates (p = 0.007). Conclusions: CBSM attenuated CTRA gene expression during the initial year of breast cancer treatment. In turn, greater increases in CTRA gene expression predicted shorter long-term DFS. These findings identify a biobehavioral oncology pathway to examine in future work. (C) 2016 Elsevier Ltd. All rights reserved.