Complementary and Alternative Medicine Use: Impact on Survival among Patients with Gastrointestinal Cancers.

BACKGROUND: A subset of patients uses complementary and alternative medicine (CAM) despite advances in gastrointestinal (GI) cancer treatment. Given that the impact of CAM utilization on survival remains not well defined, we sought to identify predictors of CAM use, as well as characterize the association of CAM on long-term survival among adults with GI cancer. METHODS: Using 2010-2019 National Cancer Database data, GI cancer patients were identified and categorized based on receipt of traditional therapy, CAM only, combination CAM plus traditional therapy, or no treatment. Multivariable Cox and logistic regression models were used to identify predictors of CAM use and estimate associations with overall survival. RESULTS: Among 1,526,482 patients, 1,215,841 (79.6%) individuals received traditional therapy, 310,251 (20.3%) received no treatment, 197 (<0.1%) received CAM alone, and 193 (<0.1%) received combination CAM plus traditional therapy. Compared with traditional therapy, CAM alone (adjusted hazard ratio [aHR], 1.86; 95% CI, 1.37-2.51) and no treatment (aHR, 1.68; 95% CI, 1.66-1.70) were associated with higher mortality, whereas combination therapy was not (aHR, 1.00; 95% CI, 0.78-1.27). CAM use was strongly associated with pancreas (adjusted odds ratio [aOR], 10.22; 95% CI, 5.76-18.12) and liver cancer (aOR, 10.09; 95% CI, 5.11-19.90). DISCUSSION: Across GI cancer types, survival differed by treatment category with higher mortality observed among patients who used CAM alone. CAM use varied by cancer type, race, care setting, and stage. These findings can help inform patient-centered discussions in GI oncology care relative to CAM.