There is a tremendous amount of interest in the use of cannabis to treat cancer. Over the past two decades, hundreds of studies have investigated the antitumor properties of cannabinoids with promising results. Unfortunately, we are lacking critical human research that answers the questions of which specific cancers respond to cannabis, which cannabinoids to use, what dose to use and what duration of treatment is needed to achieve survivorship.
As a pediatrician who also specializes in medical cannabis treatment, I am often asked to see children who are suffering with advanced cancers. Parents seek cannabis medicine to help their children with relief of symptoms from the adverse side effects of chemotherapy and radiation. In some cases, having been told the cancer treatment is not working, parents are desperate to find a cure. I teach parents what we know and what we don’t know about cannabis use in cancer patients and in children, knowing that they must have the data to make an informed decision.
Cannabinoids have been shown in animal studies to inhibit tumor growth, cause cancer cells to commit suicide, inhibit metastasis and inhibit angiogenesis (growth of new blood vessels). There is only one study in humans that used THC in nine patients with unresponsive glioblastoma multiforme. Human trials are prohibited in the US due to the Schedule I designation of cannabis.
Multiple animal studies tell us that cannabinoids have antiproliferative effects in various tumor cell lines including breast, prostate, skin, neural, bone, and thyroid. Lymphoma and leukemia cells have also responded to cannabinoids in the lab. Additionally cannabinoids have also been shown to enhance effects of certain chemotherapeutic agents. This growing evidence has triggered the use of cannabis to treat cancer in states with medical cannabis laws.
Although most reports of cancer “cures” are anecdotal, a case report from Canada of a 14-year-old girl with an extremely aggressive form of leukemia successfully documented a dose response to cannabis oil. Chemotherapy, radiation and bone marrow transplant were unsuccessful and physicians determined there was no further treatment available. The patient’s parents began treating her with untested concentrated cannabis oil. The patient started treatment with a blast cell count (leukemia cells) of 194,000 (there should be none). By Day 5 of the oil, her blast cell count grew to a dangerously high 374,000, however with continued administration of the oil, by Day 15 her blast cell count was down to 61,000. Additionally, the patient required less painkillers and had increased alertness. The lowest blast cell count noted was 300 on Day 39. Ultimately, the child succumbed to a bowel perforation that resulted from her severely debilitated health after 34 months of chemotherapy and radiation. During oil treatment, it was learned that blast cells increased if the oil was not taken three times/day or if a new batch was started, suggesting that longer dosing intervals and lower potency oil were less effective. This patient was not on other treatment while using cannabis and the blast cell count responded to adjustments in dosing frequency and dose potency.
I am currently taking care of a teenager who was diagnosed two years ago with osteosarcoma with lung metastasis. He was treated quite aggressively with chemotherapy and multiple surgeries. When his parents brought him to see me, he had lost a large amount of weight, was in terrible pain and was on palliative chemotherapy of gemcitabine. The oncologist reported to me that there was no further treatment available. The patient was started on a regimen of high dose THC and CBD oil sublingually, starting low doses and ultimately increasing to 1,000 mg cannabinoids/day divided in three doses with a 1:1 CBD:THC ratio with instructions to continue chemo. He immediately gained weight and stopped using opiates for pain. After three months of cannabis treatment, repeat bone and PET scans revealed no evidence of disease. The patient continued on cannabis treatment but due to development of anxiety, the CBD:THC ratio was adjusted to 3:1. After another three months of oil treatment, repeat radiological evaluation revealed no evidence of disease. It is now over 18 months since starting cannabis treatment and one year off chemotherapy. The cancer has not returned despite its aggressive metastatic nature. The patient is still on cannabis and is living his life normally. What is notable in this case is that research in mice with grafted pancreatic cancer cells showed that the gemcitabine’s ability to kill cancer cells was enhanced by the addition of cannabinoids. I believe that the synergy between the chemo and cannabinoids is the reason why this teenager is in remission and that continued use of cannabis has kept the cancer from returning.
Another patient, a toddler with leukemia, came to see me as he was suffering just about every side effect from chemo. He was losing weight rapidly, and was unable to eat due to severe mucositis, the mouth sores that result from chemo. He was terribly cranky, didn’t want to play and wasn’t sleeping. He started taking just a few drops of low-dose CBD and THC oil, and has been able to eat, sleep, play and gain weight. To quote his mother, “Chemo without cannabis and chemo with cannabis has been day and night for us. He is having a much easier time with the ongoing chemo treatment since cannabis oil was added.”
Cannabis treatment for children with cancer remains controversial, however, in cases of treatment-resistant cancers and severe side effects from treatment, cannabis must be a readily available option, especially since it is significantly less toxic than most cancer treatments. In addition to the antitumor effects, cannabis can enhance the effects of some chemotherapy while making the adverse effects tolerable. In my experience, I have seen patient survival extended. We must be careful with claims of “cancer cure” but if cannabis can be rescheduled from Schedule I to Schedule II, researchers can finally find the desperately needed answers and save many lives.
- Zogopoulos, Panagiotis, et al. “The antitumor action of cannabinoids on glioma tumorigenesis.” Histology & Histopathology 30 (2015).
- Guzman, M., et al. “A pilot clinical study of Δ9-tetrahydrocannabinol in patients with recurrent glioblastoma multiforme.” British journal of cancer 95.2 (2006): 197-203.
- Miyato, Hideyo, et al. “Pharmacological synergism between cannabinoids and paclitaxel in gastric cancer cell lines.” Journal of Surgical Research 155.1 (2009): 40-47.
- Nabissi, Massimo, et al. “Triggering of the TRPV2 channel by cannabidiol sensitizes glioblastoma cells to cytotoxic chemotherapeutic agents.” Carcinogenesis 34.1 (2013): 48-57.
- Donadelli, M., et al. “Gemcitabine/cannabinoid combination triggers autophagy in pancreatic cancer cells through a ROS-mediated mechanism.” Cell death & disease 2.4 (2011): e152
- Singh, Yadvinder, and Chamandeep Bali. “Cannabis extract treatment for terminal acute lymphoblastic leukemia with a Philadelphia chromosome mutation.” Case reports in oncology 6.3 (2013): 585-592.)
- Donadelli, M., et al. “Gemcitabine/cannabinoid combination triggers autophagy in pancreatic cancer cells through a ROS-mediated mechanism.” Cell death & disease 2.4 (2011): e152.
Originally published in Mary’s Cannabis Primer, a booklet by published by Alice O’Leary Randall.