A new review of scientific literature found that cannabinoids “enhance the efficacy of chemotherapy” and showed “consistent anti-tumor effect”.
In a study published in Pharmaceuticals, researchers conducted a meta-analysis based on preclinical data to investigate the link between cannabinoid treatments and cancers of different types.
Researchers at Semmelweis University and the University of Pécs said their work “provides the most comprehensive systematic synthesis to date of preclinical evidence regarding the antitumor effects of cannabinoids across a wide spectrum of cancer models.”
Cannabis compounds are “promising as adjuncts to oncotherapy” in particular for glioblastoma, breast cancer and ovarian cancer.
The study’s authors noted that “additional supporting evidence” was available in prostate and lung cancer.
According to the study, “Glioblastoma is the tumor type that has the most reproducible data base.”
The use of cannabis as an adjunct to oncological treatments is gaining momentum. There are relatively consistent signs, particularly for glioblastoma (brain cancer) and breast tumor models.
CBD, which is non-intoxicating, “proved to have the widest and most favorable profile of all the cannabinoids in this analysis. This was due to its consistent antitumor properties and well-documented clinical safety.”
A study of animal glioblastoma models proved the most compelling, with data showing that subjects receiving cannabinoid therapy saw reduced tumor volume by an average of −980.58 mm³ compared with the control group.
For the breast cancer model, cannabinoids were associated with reduced tumor volume of −402.64 mm³ on average. When combined with the chemotherapy medication doxorubicin, the average tumor volume decrease was −1295.19 mm³ compared with doxorubicin on its own.
The researchers did note that, unlike CBD “THC produces highly variable effects”, so benefits from the therapy may not “be universal.”
The latest scientific research on the use of cannabinoids to treat cancer is presented here.
For example, another recent systemic review concluded that studies “consistently show” that the CBD is a potential “anticancer agent across different cancer types”—and that effect applies to dogs as well as humans.
A similar analysis showed that CBD “holds substantial promise as an anti-tumor agent” in addition to its other anti-inflammatory properties.
Scientists explored CBD’s effect on many types of cancer—including some of the most aggressive ones, such as glioblastoma, which affects the brain. The researchers also found that CBD can suppress the growth of cancers such as breast, colorectal and ovarian, and even prostate.
In 2025, a paper published in the journal Pharmacology & Therapeutics, assessed a range of clinical and preclinical findings that the efficacy of chemotherapy drugs can be enhanced by medical marijuana.
In a sign of greater acceptance of medical applications of cannabis, President Donald Trump’s choice to serve as the next White House drug czar has called medical marijuana a “fantastic” treatment option for seriously ill patients and said she doesn’t object to legalization, even if she might not personally agree with the policy.
Also last year, a study found that “patients with cancer using cannabis report significant improvements in cancer-related symptoms.”