Survival rate of patients with combined hepatocellular cholangiocarcinoma receiving medical cannabis treatment: A retrospective, cohort comparative study.

Background: Cholangiocarcinoma (CCA) incidence in Northeastern Thailand is very high and a major cause of mortality. CCA patients typically have a poor prognosis and short-term survival rate due to late-stage diagnosis. Thailand is the first Southeast Asian country to approve medicinal cannabis treatment, especially for palliative care with advanced cancer patients. Methods: A retrospective cohort study compared survival among 491 newly diagnosed advanced CCA patients between September 2019 and June 2021. Of these, 404 received standard palliative pain management (ST), and 87 received medicinal cannabis treatment (CT). Patients were enrolled from four tertiary hospitals and two secondary hospitals in five provinces of Northeast Thailand. Cumulative survival was calculated by the Kaplan-Meier method, and independent prognostic factors were analyzed using Cox regression. Results: For ST patients, follow-up time was 790 person-months, with a mortality rate of 48.35/100 person-months. For CT patients, follow-up time was 476 person-months, with a mortality rate of 10.9/100 person-months. The median survival time after registration at a palliative clinic was 0.83 months (95% CI: 0.71-0.95) for ST and 5.66 months (95% CI: 1.94-9.38) for CT. Multivariate analysis showed CT was significantly associated with prolonged survival (HRadj = 0.28; 95% CI: 0.20-0.37; p < 0.001). Conclusions: The medical cannabis increased overall survival rates among CCA patients. In this retrospective cohort, Medicinal cannabis treatment was associated with more prolonged survival among advanced CCA patients in Northeastern Thailand. While this association remained significant after multivariable adjustment, unmeasured or residual confounding factors may have influenced the observed outcomes. Although the association remained significant after adjustment, unmeasured or residual confounders may have influenced outcomes. Further prospective studies are warranted to confirm these findings and explore potential mechanisms.