Groundbreaking Meta-Analysis Reveals Compelling Evidence for Cannabis in Easing Cancer Symptoms

Cancer Playbook and WHOI have analyzed data from over 10,000 peer-reviewed studies and have published largest research review on medical cannabis and its effects on cancer-related symptoms in Frontiers in Oncology.

The meta-analysis has revealed a striking 3:1 ratio of studies showing cannabis is effective versus ineffective in treating cancer symptoms. This level of scientific consensus is rare in biomedical research and even rivals or surpasses that of many FDA-approved drugs.

Key findings from the meta-analysis are as follows-

• Cannabis reduced cancer cell proliferation

• It inhibited metastasis, limiting cancer spread

• It increased apoptosis (natural cancer cell death)

• It has a profound anti-inflammatory effect, a critical factor since inflammation is linked to over 80% of the world’s most debilitating chronic diseases

“We expected controversy. What we found was overwhelming scientific consensus,” said Ryan Castle, Head of Research at Whole Health Oncology Institute. “This is one of the clearest, most dramatic validations of medical cannabis in cancer care that the scientific community has ever seen.”

Though this study is based on peer-reviewed work, Cancer Playbook makes the case that research can only paint part of the picture. By building on a dual foundation of research and patient experience, Cancer Playbook is redefining cancer support. The platform blends cutting-edge research with Patient Reported Outcomes (PROs), crowdsourcing real-world data from people living with cancer.

“The science matters. But so does the patient,” said Castle. “We are trying to support whole human beings, and that starts by listening to them.”

The significance of PROs is growing rapidly in modern medicine, as traditional clinical trials measure biological responses but often overlook what the patient is actually going through. PROs fill that gap, turning subjective experiences-like pain, fatigue, or emotional distress-into scientifically valid data. This is especially critical when looking at treatments like cannabis, where personal experience plays such a pivotal role in perceived and measurable benefit.

“Too often, people turn to cannabis as a last resort. We believe it should be part of the conversation from day one,” said Jim Gerencser, Founder of Cancer Playbook. “Refer to us at Cancer Playbook first as you weigh conventional treatment options. Don’t wait until traditional options have been exhausted. Whether or not you choose cannabis, we offer a fuller picture of what’s possible-one rooted in evidence, experience, and a belief that patients should be at the center of their own care. This platform was built for patients, by patients, backed by the best data in the world.”

Reference:

Ryan D. Castle, James Marzolf, Meta-analysis of medical cannabis outcomes and associations with cancer, Frontiers in Oncology, https://doi.org/10.3389/fonc.2025.1490621.