Marijuana Use Popular Among Patients With Cancer

Nausea, lack of appetite and anxiety are a few of the cancer-related side effects that patients can experience. To ease the burden, many of them may turn to medical marijuana, which is legal in 29 states and Washington, D.C.

A recent study conducted by researchers at the Seattle Cancer Care Alliance in Washington state, where medical and recreational marijuana use is legal, examined the popularity of cannabis in this population.

Among 926 patients surveyed, where the median age was 58, 66 percent had previously used marijuana. Further, 24 percent used it in the last year and 21 percent in the past month.

Please briefly explain the study's findings.

CURE spoke with study author Steven A. Pergam, M.D., M.P.H., Associate Member, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, about what the findings could mean in the broader sense of health care.We found that close to one-quarter of patients with cancer who responded to our survey used cannabis. Those that reported active use came from a broad spectrum of patients across all age ranges and types of cancer.

Patients used cannabis primarily for physical symptoms such as pain, nausea and to help increase appetite, but, interestingly, also used it frequently for symptoms such as coping with their illness, to deal with stress or to manage depression.

Patients with cancer who completed the survey were interested in learning more about cannabis during their treatment, regardless of active use.

Were you surprised to see these results?

Finally, and perhaps most importantly, although patients wanted to get information about cannabis use during their cancer treatment from their providers, they were more likely to get this information from non-scientific sources.Yes and no. We expected there to be a lot of interest, but at the same time we didn't have any idea what the frequency of use might be.

We anticipated that patients would report using cannabis for nausea or as an appetite stimulant, as these symptoms are where cannabis is most frequently purported in the lay press and online forums to provide benefits.

The frequency for which patients reported using cannabis for symptoms such as dealing with stress, coping with their illness and depression was unexpected.

Why are patients drawn to using recreational marijuana?

Despite a lack of scientific evidence, more than a quarter of patients thought that cannabis was helping to treat their cancer. This indicates a need to better educate patients.There are lots of reasons patients might choose cannabis. This is particularly challenging to answer, as decisions that are made around cancer are often very personal and likely vary between patients.

Our data suggests, however, that only a small percentage of patients used cannabis for recreational reasons. Most used it to help manage their symptoms.

The surveys were taken by patients in Washington, where medical and recreational use of marijuana is legal. Do you expect findings to be very different in places where it is not legalized?

What kind of overreaching message can these findings present to the medical community?

Without data from other sites around the country, this is hard to speculate. We would like to see additional studies that attempt to replicate our findings, because we don't know if these data reflect national trends or a snapshot in a community where recreational cannabis is more readily available.We hope that these data drive providers to start asking their patients about cannabis use. It is imperative that providers engage in these conversations, no matter if it is in a state with legalized recreational or medical cannabis, or in those places where the drug remains illegal.

Cancer providers have an opportunity to help patients make informed decisions, and to avoid potential risks that might be associated with use. If we don't ask patients about cannabis, we might miss these opportunities.

In those with very weakened immune systems, such as patients with leukemia or those undergoing a bone marrow transplant, I actively discourage patient use because of the potential increased risk of fungal pneumonia. That is in contrast to a patient in palliative care, where the benefits may outweigh the risk.

What further research needs to be conducted?

It is important for patients to understand that not all cancers and treatments are the same. By discussing their use or interest in cannabis with their providers, their cancer team can help them to make more informed decisions.We want others to replicate our study in different centers. Future studies that focus on cancer providers’ perceptions of cannabis use among their patients are also important, so that we can help tailor educational tools about cannabis and cancer for those that care for these complex patients.

Eventually, I also hope to see more rigorous clinical trials aimed at addressing the potential risks and benefits of marijuana in cancer care. The more data we have the better we will be able to educate and protect our patients.