Cannabinoid consumption among cancer patients receiving systemic anti-cancer treatment in the Netherlands

Purpose: Despite the inconclusiveness regarding health effects of cannabinoids among cancer patients, studies from non-European countries suggest that the medical-intended consumption of such products by this patient group is significant. The current study analyses cannabinoid usage among oncology patients receiving systemic treatment in the Netherlands. Methods: The current study included adult patients receiving intravenous systemic therapy at Maastricht Comprehensive Cancer Centre, for a solid malignancy. Participants were asked to complete an anonymous questionnaire including questions on demographic variables, clinical variables and cannabinoid consumption. Results: A total of 153 patients with solid cancer were included in this study. Almost 25% reported usage of cannabinoids for medical purposes, with 15% of the patients currently using the substance. Additionally, 18% of non-users considered future medical usage. In 48% of the cases, consumption was reported by the oncologist. The proposed anti-cancer effect was reported by 46% of the users as motivation for consumption. Current users were mainly palliative patients and 54% of the users were undergoing immunotherapy. Intention of treatment and type of therapy were predictive factors for consumption. Cannabinoid-oil was the most frequently used way of consumption. Conclusion: This study underlines the high number of cannabinoid users among oncology patients in the Netherlands in presumed absence of clinical guidance. It highlights the essence of a pro-active role of the clinician, assessing cannabinoid usage and educating the patients on the most recent evidence regarding its potential benefits and risks. Further studies on clinical decision making and efficacy of cannabinoids are recommended, to improve clinical guidance.