While cannabis is certainly not an accepted form of treatment to eliminate or cure cancer, it has been shown to have some helpful properties. More randomized, controlled clinical studies are necessary to validate any claims in humans, and most studies are in vitro (test tube) or animal (rats) models. This is in part due to government restrictions on the research of cannabis that is allowed in our country, but this paradigm is changing and more research is now being allowed.
Numerous studies in mice and rats have shown that cannabinoids may inhibit tumor growth by causing cell death (apoptosis), blocking cell growth, and blocking the ability of tumor cells to get a blood supply to multiply (angiogenesis). Some lab studies have demonstrated that cannabinoids can kill cancer cells while protecting healthy cells.
A study in mice has shown that cannabinoids may protect against inflammation of the colon and thereby reduce the risk of colon cancer, and possibly aid in its treatment. Also, cannabinoids have been shown (delta-9-thc) to damage or kill hepatocellular carcinoma (liver cancer). Mouse models have also shown that it had an anti-tumor effect in non-small cell lung cancers, as well as breast and prostate cancer. Other studies show that it also may decrease the chance of bladder cancer by 40% in chronic users.
A study by the pulmonologist Donald Taskin from San Diego also demonstrates that in humans, cannabis smoking does not increase the risk of lung cancer. Although cannabis smoke has similar toxins as tobacco, the cannabinoids present offer a protective shield and can actually reduce the incidence of lung cancer in users compared to a control group. However, we always recommend vaporizing instead of combustion and smoking of cannabis.
Cannabidiol (CBD) has been shown to cause cancer cell death in breast cancer cells in lab models, and mouse models have shown that cannabinoids may lessen the growth, number, and spread of tumors.
A review of 34 studies also shows that in all but one study, cannabinoids can be effective in Glioma and Glioblastoma (brain cancer). A lab study has shown that CBD in conjunction with chemotherapy may make treatment for glioma more effective with higher cancer cell death without harming normal cells in rodent models.
For chemotherapeutic protocol for Glioma or GBM, THC has been shown to be an effective potentiator of temozolomide (the current standard chemotherapeutic agent) used to treat the disease. The combination of THC and temozolomide worked better at arresting tumor growth than either drug alone. Once again this was a study in laboratory rats, not humans, but still worth further trials and investigation.
Stimulating appetite - many animal studies have shown that delta-9-THC and other cannabinoids stimulate appetite and can increase food intake. This is important to allow normal nutrition and weight maintenance during cancer treatments. Especially important to allow patients with cancer of the head and neck to maintain health and weight during chemoradiation, most cancer patients universally suffer from lack of appetite and severe weight loss. This "wasting syndrome" or Cachexia, is benefitted tremendously thru the use of cannabis during cancer treatments and is well recognized. It simply allows the patient to eat more readily and fully, and not suffer the nutritional deficits associated with lack of eating and appetite suppression.
Pain Relief - cannabinoid receptors have been studied in the brain, spinal cord, and peripheral nerve endings thru-out the body to understand the mechanism of pain relief. These receptors also possess anti-inflammatory effects that play a role in pain relief. Animal studies have indicated that cannabinoids may prevent nerve pain, numbness, tingling, swelling, and muscle weakness caused by some types of chemotherapy.
Nausea and vomiting - one of the side effects of chemotherapy that occurs routinely is nausea and vomiting. Typically standard drugs are given to mitigate this effect, either along with the chemo, or several days after the chemo is administered. However, some of these agents have adverse or objectionable side effects and are not totally effective. Standard of care now dictates that drugs like AMEND or equivalent be used at the time of chemo injection, but this does not remain effective 2 days later when most side effects occur. Cannabis has been used with a high degree of success in this regard and should be routinely available and offered for all patients receiving chemotherapy. Just a few puffs of the vapor or smoke from cannabis almost cause instant relief... this is perhaps one of the most beneficial uses in cancer, in addition to weight gain and staying nourished.
Anxiety and sleep - the use of proper strains of medicinal cannabis, the correct dosage, and suitable ingestion technique can result in a reduction in the anxiety that many cancer patients logically have as a result of their diagnosis or treatment. However, please be advised that if used improperly, or too high a dose, it may also increase anxiety, so caution is recommended here. Also, it has been shown to be an effective agent for insomnia and can help promote sleep in cancer patients who use it correctly. Initially, stimulation may be expected by the use of cannabis, but after a time period of generally 1-2 hours, it can cause sleepiness and sedation and allow you to fall asleep more readily. Edibles may be particularly beneficial in this respect, due to their long action and stronger effect. However, they must be ingested and conditions do not always permit oral ingestion due to nausea and vomiting.