Cancer Patients School Clinicians About Marijuana

Role Reversal in Colorado

Nick Mulcahy

June 10, 2019

CHICAGO — Ashley Glode, PharmD, a pharmacist in the gastrointestinal clinic at the University of Colorado Cancer Center, Anshutz, says marijuana is not a taboo topic in her state, where medical use was approved in 2000 and recreational use in 2012.

Cancer clinicians at the center regularly have discussions regarding patients' use of marijuana, and patients also often ask about usage.

However, Glode discerned a pattern in the conversations: "A lot of staff say they just don't feel comfortable answering patients' questions or aren't sure what to say to patients."

The 35-year-old assistant professor of clinical pharmacy and her colleagues wondered how this was playing out in other clinics across the state.

So, they partnered with a survey expert at the university, constructed a poll to be answered anonymously, and distributed it via the Rocky Mountain Oncology Society, an American Society of Clinical Oncology (ASCO) regional affiliate, as well as through their network of referring practitioners.

Here at the ASCO 2019 Annual Meeting, Glode and her team reported the results: although nearly 75% of oncology clinicians in Colorado believe marijuana provides a medical benefit to cancer patients, 55% also said they were not comfortable recommending it for cancer-related symptoms.

Glode interpreted the beliefs of a large swath of 172 respondents: "Marijuana's important, but I'm not sure how to do it."

The survey's "most surprising" finding, Glode told Medscape Medical News, was about how oncology providers receive information about medical marijuana. Most commonly, it's from patients (68.4%).

Traditional sources of information for healthcare professionals lagged behind, per the survey: other providers (53.2%), medical journals (51.5%), and lectures (43.9%). "They're teaching us," Glode said about cancer patients and marijuana.

We aren't the ones studying marijuana. Dr Ashley Glode

That's role reversal, she suggested. "We aren't the ones studying marijuana. We aren't the experts. They are."

In effect, it is individualized medicine, said Glode: "Patients are trying different things and figuring out what works."

For example, cancer patients inform clinicians of their marijuana product choices and about how they felt before and after they took it with regard to disease- and treatment-related symptoms. "They bring in the wrappers of old edibles to help you," she said, referring food-based marijuana products such as brownies. Patients also recommend certain dispensaries on the basis of experience; medical marijuana patients fill their prescriptions at dispensaries, not pharmacies, because under federal law, marijuana is classified as a schedule I drug.

To some extent, cancer clinicians have become "conduits" for patients to pass along information to other patients, said Glode.

Cancer patients are filling an information vacuum, she suggested.

That idea was reinforced by Mellar Davis, MD, Geisinger Medical Center, Danville, Pennsylvania, who moderated a panel on cannabis at the ASCO annual meeting and told Medscape Oncology that "there are no guidelines that direct physicians on how or when to use [marijuana]."

The idea that patients are teaching physicians about marijuana for cancer did not faze Brooke Worster, MD, medical director, Neu Center for Supportive Medicine and Cancer Survivorship, Thomas Jefferson University, Philadelphia, Pennsylvania.

Patient and family advocates and political sentiment — not physicians or their professional groups — have generated the legislative changes on medical cannabis, said Worster, who was asked for comment.

"Most patients will tell you that their physicians aren't even willing to talk about cannabis," she added.

Worster and colleagues conducted a survey of more than 200 physicians of all specialties in the Philadelphia area, and more than 90% of them said they felt mostly or completely uneducated about cannabis. "This needs to change!" she told Medscape Medical News in an email.

Physicians need to adjust their attitudes, suggested Worster, who gave a talk at the ASCO meeting about the potential risks and benefits of cannabis use in older (aged 70+) cancer patients.

"Cannabis will never mirror the rigorous process that any other pharmaceutical interventions follow, so physicians need to embrace and support data and research behind its use, side effects, and contraindications," she said.

Why Patients Are the Researchers

The Colorado survey respondents, who included a mix of oncologists, oncology nurses, pharmacists, and advanced practice providers, such as physician assistants, said their main concerns about recommending medical marijuana were as follows:

  • uncertain dosing (83%)

  • limited knowledge of available products; where to buy (73.1%)

  • interactions with other medications (64.9%)

  • legal issues/liability concerns (56.1%)

  • limited evidence of effectiveness (46.2%)

"The big take-away message from the survey is that there is a need for education and research," said Glode.

Research is happening slowly — but not always in the traditional mode — at the University of Colorado.

Owing to a legal prohibition against having patients ingest marijuana on campus, researchers interested in evaluating the pharmacokinetics of the drug have gotten "creative," said Glode.

For example, at the University of Colorado, Boulder, physicians from the school's Cancer and Health: Research on Marijuana Edibles (CHROME) project are studying stage 3 and 4 cancer patients who use cannabis to treat symptoms. The patients all go to a single dispensary and purchase a specific edible product.

The research team has a "mobile laboratory" — a van that drives to the study patients' homes. The team conducts four blood draws in the van after the patients have ingested marijuana in their home. Patients also undergo brief cognitive tasks and take quick surveys in the van.

These are not optimal research conditions, suggested Glode.

Meanwhile, cancer patients stream into clinics throughout the University of Colorado system and regularly report on their symptoms and how medical marijuana does or doesn't help. It's a steady accumulation of "n-of-1" studies, said Glode.

There is not a lot of research about marijuana for cancer patients by academics, she observed.

"We've been brainstorming about having a symposium here in Colorado, but the issue is, who do you have come and talk?," said Glode.

In lieu of academic experts, the University of Colorado personnel have considered inviting marijuana dispensary staff and asking: "What do you tell patients?"

Glode has served as a consultant to Heron Therapeutics. A coauthor has financial ties to multiple pharmaceutical companies. Worster has disclosed no relevant financial relationships.

American Society of Clinical Oncology (ASCO) 2019: Abstract 10511. Presented June 1, 2019.

Follow Medscape's Nick Mulcahy on Twitter

For more from Medscape Oncology, follow us on Twitter


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.