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Observational Study
. 2026 Feb;33(2):1370-1380.
doi: 10.1245/s10434-025-18552-7. Epub 2025 Oct 24.

Cannabis, Pain, and Complications: A Prospective Analysis of Cannabis Use, Opiate Consumption, and Postoperative Outcomes following Cancer-Related Abdominal Surgery

Elliott J Yee  1 , Michael J Kirsch  1 , Owen S Miller  2 , Cristina Sempio  3 , Jacquelyn Bainbridge  2 , Jost Klawitter  3 , Uwe Christians  3 , Helen Madsen  3 , Martin D McCarter  1 , Ana L Gleisner  1 , Ramakrishna Gumidyala  3 , Emily Lindley  4 , Michelle Adkins  2 , Nicole Semmler  2 , Camille L Stewart  5
Affiliations
Observational Study

Cannabis, Pain, and Complications: A Prospective Analysis of Cannabis Use, Opiate Consumption, and Postoperative Outcomes following Cancer-Related Abdominal Surgery

Elliott J Yee et al. Ann Surg Oncol. 2026 Feb.

Abstract

Background: Cannabis use is increasing and is of particular interest to patients with cancer. There is no prospective data regarding its impact on perioperative outcomes. We asked how chronic usage of cannabis compounds (cannabinoids) impacted postoperative pain, opiate use, and complications after abdominal surgery for the treatment of cancer.

Patients and methods: This was a single center prospective observational cohort study conducted from 9/2021-3/2024 of patients 21+ years old, undergoing abdominal surgery for the treatment of cancer, and either chronic cannabinoid users (≥1x/week for last 3 months) or non-users (for the last year). Plasma cannabinoids were measured preoperatively on the day of surgery.

Results: Of 223 patients screened, 64 subjects completed enrollment (24 chronic cannabinoid users, 40 non-users). Most were male (67%) and underwent an open abdominal surgery (75%). 41% developed complications, 23% of which were severe (grade 3+) complications. Chronic users with detectable cannabinoid levels had significantly higher pain scores, which persisted in multivariable analysis. Chronic users also received significantly more morphine milligram equivalents (MME) (8-hours postoperatively: 28.8 vs 9.8, p=0.036, during the total hospitalization: 273 vs 202.1, p=0.046, prescribed: 150 vs 100, p=0.047, taken through POD30: 67.5 vs 5, p=0.03). Differences in MME prescribed and taken postoperatively persisted in multivariable analysis. Chronic users had fewer overall complications (5/23 (22%) vs 21/41 (51%), p=0.025), but similar frequency to non-users for severe complications (2/23 (8.7%) vs 4/41 (9.8%), p=0.33).

Conclusions: Chronic cannabinoid use increased postoperative pain and MME use for patients undergoing abdominal surgery for the treatment of cancer, but did not increase complications. Further study regarding preoperative cannabinoid cessation and use of cannabinoids for postoperative pain is warranted.

Keywords: Cancer; Cannabis; Complications; Pain; Surgical oncology.

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References

    1. Kenyon J, Liu W, Dalgleish A. Report of objective clinical responses of cancer patients to pharmaceutical-grade synthetic cannabidiol. Anticancer Res. 2018;38(10):5831–5. - DOI - PubMed
    1. Compton WM, Han B, Jones CM, Blanco C, Hughes A. Marijuana use and use disorders in adults in the USA, 2002–14: analysis of annual cross-sectional surveys. Lancet Psychiatry. 2016;3(10):954–64. - DOI - PubMed
    1. Denial of Petition To Initiate Proceedings To Reschedule Marijuana; Proposed Rules and Applications To Become Registered Under the Controlled Substances Act To Manufacture Marijuana To Supply Researchers in the United States: Policy Statement. Department of Justice DEA. 2016
    1. Stewart C, Fong Y. Perioperative cannabis as a potential solution for reducing opioid and benzodiazepine dependence. JAMA Surg. 2020. https://doi.org/10.1001/jamasurg.2020.5545 . - DOI - PubMed
    1. Klawitter J, Sempio C, Mörlein S, et al. An atmospheric pressure ionization MS/MS assay using online extraction for the analysis of 11 cannabinoids and metabolites in human plasma and urine. Ther Drug Monitor. 2017;39(5):556. - DOI

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