Cannabis Use Among Cancer Patients Rose at the Same Rate as the General Population Regardless of State Laws | Research

The takeaway

Cannabis use increased 55-60% between 2013 and 2019 among both cancer patients and the general population, with state legalization policies not uniquely driving use among cancer patients.

Cancer patients, oncologists, and policymakers evaluating medical cannabis program effectiveness.

Cancer patient cannabis use: 6.6% to 10.6% (2013-2019)

What the researchers found

Cannabis use prevalence among people with a cancer diagnosis rose from 6.6% in 2013 to 10.6% in 2019 (approximately 60% increase), mirroring the 11.8% to 18.6% increase in the general population. The trends were similar regardless of whether states had illegal, medical-legal, or non-medical legal cannabis policies.

Why it matters

The finding that cancer patients are not using cannabis at higher rates in legal states challenges the assumption that medical legalization primarily benefits patients with serious illnesses. Instead, cannabis use trends among cancer patients simply reflect broader population trends.

The numbers in context

Cancer patients: 6.6% (2013) to 10.6% (2019), approximately 60% increase. General population: 11.8% to 18.6%, approximately 58% increase. Highest prevalence in non-medical legal states for both groups. Similar trends across all policy categories.

How the study worked

Analysis of five waves of the nationally representative PATH Study (2013-2019). Past-year cannabis use prevalence was compared between those with and without cancer diagnoses, stratified by state cannabis policy status. Demographic and policy correlates were examined.

What this study cannot tell us

PATH Study self-report may undercount cannabis use. Cancer diagnosis was self-reported and could not be verified. The study period ends in 2019, before the most recent wave of legalizations. Cancer type, stage, and treatment status were not examined.

How to read the evidence

Nationally representative longitudinal data from the PATH Study with five waves of assessment. Strong population-level evidence for trends, though self-reported diagnoses and use introduce uncertainty.

When this study was published

Published in 2025 with PATH Study data from 2013-2019.

The bigger picture

Medical cannabis laws were originally justified as providing access for patients with conditions like cancer. This study suggests that cancer patients are not disproportionately affected by policy changes; their use simply mirrors broader societal trends. This raises questions about whether current medical cannabis programs are effectively reaching their intended patient populations.

Questions still open

If cancer patients are not using cannabis more in legal states, are medical cannabis programs serving their intended purpose? Are there barriers preventing cancer patients from accessing medical cannabis that track with broader population access?

Common questions

Are cancer patients using cannabis more because of legalization?

Not uniquely. Cancer patients showed the same rate of increase as the general population, and the trends were similar across states regardless of legal status. This suggests broader cultural shifts rather than policy-driven access.

Is cannabis use among cancer patients a concern?

It depends on context. Some cancer patients use cannabis for symptom management with potential benefits. However, at a population level, the study did not examine whether cannabis use was helpful or harmful for cancer outcomes.

Read the original research

Trends in cannabis use among those with and without a cancer diagnosis according to state-level cannabis policy: findings from the PATH Study, Waves 1-5 (2013-2019).

Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer, 33(7), 560

View on PubMed ↗Publisher’s paper ↗

Citation

Martin, Connor D; Rivard, Cheryl; Kasza, Karin; Case, Amy A; Hansen, Eric; Goniewicz, Maciej L; O'Connor, Richard J; Hyland, Andrew; Smith, Danielle M. (2025). Trends in cannabis use among those with and without a cancer diagnosis according to state-level cannabis policy: findings from the PATH Study, Waves 1-5 (2013-2019).. Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer, 33(7), 560. https://doi.org/10.1007/s00520-025-09617-0