Medical cannabis use in oncology and associated outcomes: A scoping review

Natural and synthetic cannabinoids are being used worldwide to treat various symptoms in cancer patients. This study aims to map the therapeutic benefits and adverse effects associated with the use of cannabis-based drugs in these outcomes.

Following Joanna Briggs Institute guidelines a scoping review was conducted. The study protocol was available in the Open Science Framework public repository. An extensive search strategy involving databases like Cochrane Library, Embase, CINAHL, Medline/PubMed, Lilacs, Google Scholar, and Open Gray for gray literature analysis was executed by a skilled librarian. The inclusion criteria were primary studies (observational and randomized) that evaluated the efficacy and safety of cannabinoids in cancer patients. The review encompassed studies of diverse designs, publication years, and types, as long as they addressed cannabinoids' impact in oncology.

Twenty-nine (82.86%) out of total of 35 were randomized and 6 (14.14%) were non-randomized. About 57.1% of studies utilized registered products as interventions, with THC being the most natural cannabinoid cited in variable doses and administration routes. Moreover, 62.85% of studies specified the cancer types (breast, lung, sarcomas, hematological and reproductive system), while only one study detailed cancer staging. The evaluated outcomes encompassed nausea and vomiting (77.14%), appetite (11.43%), pain (8.57%), and tumor regression (2.86%) across different proportions of studies.

Cannabinoids show promise in managing pain, emesis, and anorexia/cachexia linked to cancer progression. New randomized clinical trials with a larger number of participants and observational studies on long-term safety are crucial to affirm their medicinal utility for cancer patients unresponsive to conventional drugs.