Colorectal cancer adjuvant chemotherapy trends among a nonelderly veteran cohort at a southern veterans health administration

BACKGROUND: For patients with high‐risk stage II or stage III colorectal cancer (CRC), adjuvant chemotherapy (AC) improves survival, yet use varies substantially across medical oncology settings. AIM: Utilization of guideline concordant CRC AC was assessed at a Veterans Health Administration (VHA) facility to determine quality improvement initiatives. METHODS AND RESULTS: The study was a retrospective review of CRC surgeries from January 1, 2000 to December 31, 2015 at a South Regional VHA. Inclusion criteria consisted of pathologic high‐risk stage II or stage III CRC, with exclusion for age ≥80, age ≥75 hospitalized with major co‐morbidity in the prior year, and death or discharge to hospice within 30 days of the index surgery. The primary predictor was year‐group; partitioned 2000–2005, 2006–2010, 2011–2015 to account for changes in NCCN high risk stage II definitions. Primary outcome was AC receipt. Secondary outcome was reason for chemotherapy omission. Among 180 eligible surgeries (121 colon and 59 rectal cancers), patients were mostly male (96%), white (79%) and with median age 64 years. Overall, 117 (65%) received AC. Compared to 2000–2005, patients undergoing surgery between 2011 and 2015 were less likely to receive AC (odds ratio 0.35; 95% confidence interval [CI] 0.14–0.82), due to more patients declining AC (27% vs. 6%, p < .01) in the NCCN eligible cohort (N = 180), and (32% vs. 8%, p < .01) in an analysis of patients who completed appointments and had AC recommended by providers (N = 146). CONCLUSIONS: Survival benefitting AC decreased over time among a nonelderly Veteran cohort eligible for AC. Evaluating care decisions and trends within other VHA facilities and outside the VHA are warranted.