Testicular germ cell tumours (TGCTs) are the most common malignancy among young men, and their rapidly increasing incidence suggests a role for modifiable risk factors. The role of increasingly prevalent cannabis use, particularly during developmental periods before biological maturation, in TGCT etiology remains unclear.
The association between cannabis use in adolescence and early adulthood and TGCT was assessed in a nationwide hospital-based case-control study in France (454 cases, 670 controls). Exposure was characterized by timing and frequency, including persistent use. Weekly-equivalent exposure scores were used to approximate exposure-response. Conditional logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs), overall and by histological subtype.
Cannabis use was not consistently associated with TGCT risk overall. Associations varied by timing and histological subtype. Early adulthood daily use was associated with increased TGCT risk overall (OR baseline=1.50, CI 1.02-2.19) and with seminoma (OR baseline=2.02, CI 1.22, 3.33; OR adjusted=1.93, CI 1.13-3.31), adjusted for tobacco, alcohol, and education. Exposure-response was observed in early adulthood (p-trend = 0.046), particularly for seminoma (p-trend = 0.016). Weekly use across 12-25 years was associated with increased TGCT risk (OR adjusted=1.85, CI 1.11-3.07), with similar patterns for seminoma (OR adjusted=2.29, CI 1.09-4.79). No associations were observed in adolescence or for non-seminoma.
Findings support an effect of cannabis use during early adulthood on TGCT risk with significant dose-response relationships and stronger associations for daily use, particularly for seminoma; however, subtype results require cautious interpretation and independent confirmation.
European journal of cancer (Oxford, England : 1990). 2026 Jul 09 [Epub ahead of print]
Astrid Coste, Bayan Hosseini, Delphine Praud, Amina Amadou, Jeanne Perrin, Barbara Charbotel, Joachim Schüz, Béatrice Fervers, TESTIS study group
Department of Cancer Prevention and the Environment, Centre Léon Bérard, Lyon, France; Inserm UMR U1296, Radiations: Defense, Health, Environment, Lyon, France. Electronic address: ., Department of Cancer Prevention and the Environment, Centre Léon Bérard, Lyon, France; Inserm UMR U1296, Radiations: Defense, Health, Environment, Lyon, France. Electronic address: ., Department of Cancer Prevention and the Environment, Centre Léon Bérard, Lyon, France; Inserm UMR U1052, Centre de Recherche en Cancérologie de Lyon, Lyon, France. Electronic address: ., Department of Cancer Prevention and the Environment, Centre Léon Bérard, Lyon, France; Inserm UMR U1296, Radiations: Defense, Health, Environment, Lyon, France. Electronic address: ., Laboratory of Reproductive Biology-CECOS, Clinical-Biological Centre of Assisted Reproductive Medicine, Hopitaux Universitaires de Marseille, Marseille, France. Electronic address: ., UMRESTTE, UMR T 9405, IFSTTAR, Lyon 1 University, Eiffel University, Lyon, France. Electronic address: ., Environment and Lifestyle Epidemiology Branch, International Agency for Research on Cancer, World Health Organization, Lyon, France. Electronic address: ., Department of Cancer Prevention and the Environment, Centre Léon Bérard, Lyon, France; Inserm UMR U1052, Centre de Recherche en Cancérologie de Lyon, Lyon, France. Electronic address: .