A lung cancer patient who refused conventional treatments in favour of CBD oil has piqued the curiosity of doctors in the UK after her tumour began to shrink.

While it is unclear why her condition improved, the lead author of the case report published in The BMJ has called for more research into CBD oil and its treatment potential.

Lead author Dr Kah Ling Liew, from The Princess Alexandra Hospital respiratory department, told Gizmodo: “Of course we are unable to confirm causation from this single case; however, spontaneous regression in such cases is extremely rare. The only difference in this case was the ingestion of the CBD oil.”

The woman in her 80s first presented to her GP in February 2018 with a persistent cough. After many tests, she was diagnosed with non-small cell lung carcinoma in July that year.

After declining conventional treatment, her doctors decided to take a ‘watch and wait’ approach by carrying out regular CT surveillance. 

Cannabinoid Oil In Laboratory - Medical Cannabis Australia - Cannabiz

Unbeknown to her medical team, the patient was self-administering CBD oil orally two-to-three times daily from August 2018 onwards. She made no other changes to her lifestyle and diet and continued to smoke. 

Regular CT scans were carried out over the following two-and-a-half years at intervals of three to six months. The scans showed the lung cancer to be shrinking, with the initial lesion — 41mm in June 2018 — reducing by 76% to 10mm by February 2021.

When questioned by doctors, the patient disclosed her CBD use. 

On further investigation, the doctors discovered she was taking oil that contained 19.5% THC, 20.5% CBD and 23.8% THCA, and had been advised by her dealer not to take it with hot food or drink. 

While the case study authors cannot confirm that the patient’s use of CBD oil caused her tumour to shrink, they conclude that the potential for cannabinoids to be used to augment conventional primary cancer treatments justifies further research. 

Dr Liew noted the woman is still alive and, as of her most recent check-up this year, the cancer doesn’t seem to be making a comeback and is now so small that the scans used to track it can no longer measure its size. 

She added: “CBD/THC deserves further study as a primary form or adjunct for cancer treatment as [it] seems to be minimally invasive. Of course, even if CBD/THC could help treat some people’s cancer, the authors wouldn’t expect it to be a panacea… given how different an individual cancer can be from another. There will not be a single treatment that works for every form of cancer.”

“Clinicians need to be aware that their patients may be taking non-conventional and unlicensed treatments without their knowledge, and it is always important to consider a patient’s choices when discussing treatment options.”

Hannah Adler

Hannah is a communications professional and early-career researcher in the disciplines of health communication and health sociology. She is a PhD student at Griffith University currently writing a...