Cancer is the single leading cause of death worldwide and was responsible for 7.6 million deaths in 2008. While research in this field of medicine continues to be actively pursued, the death toll from cancer is projected to reach 13.1 million by 2030.
Among the many forms of deadly cancer, pancreatic cancer remains one of the most common and difficult to treat. On the other hand, growing interest in the cancer-fighting abilities of cannabinoids – compounds found in medical marijuana – has resulted in an accumulation of positive evidence that can no longer be ignored.
What is Pancreatic Cancer?
Pancreatic cancer affects an organ of the digestive system known as the pancreas. Pancreatic cancer is one of the most aggressive forms of cancer and is the fourth most common cause of cancer-related death in the United States.
The reason why pancreatic cancer is so deadly is because of its rapid rate of metastasis – the spreading of cancer to other areas of the body. Upon diagnosis, 85% of patients already show signs of metastasis, commonly in the lymph nodes, liver and lungs. As a result, surgical interventions are considered in only 15 to 20% of pancreatic cancer cases. Even still, more than 80% of patients who undergo surgery fail to survive for longer than 5 years following the procedure.
Chemotherapy is the most common treatment for the vast majority of patients who do not qualify for surgery. However, life expectancy is even worse in patients who undergo chemotherapy treatment, averaging to only about one year.
Due to the poor survival rates of patients with pancreatic cancer, researchers continue to search for unique ways of treating this deadly disease.
How Can Marijuana Help?
Emerging evidence has identified the endocannabinoid system as a promising target for cancer research, based on studies which show that cancer cells exhibit higher levels of cannabinoid receptors as well as studies which show that cannabinoids possess unique cancer-fighting properties.
Among the growing body of cancer research involving the endocannabinoid system, research on pancreatic cancer seems to be very limited. In our review of the scientific literature, we were only able to identify 2 studies that directly investigated the role of cannabinoids in pancreatic cancer.
The first study was published in 2006 by a team of Spanish researchers, who found that cannabinoids – including natural and synthetic versions of THC – were able to reduce the growth of tumors in two different animal models of pancreatic cancer. Interestingly, the study found that while cannabinoids were able to induce apoptosis (cell death) of tumor cells, normal pancreatic cells were left unaffected.
The study also found that cannabinoids were able to inhibit the spreading of pancreatic cancer not only to nearby tissues such as the spleen, but also to more distant tissues such as the liver, diaphragm, stomach and intestine. As a result, the researchers suggest that cannabinoid treatment could reduce pancreatic cancer metastasis, which is perhaps the most deadly aspect of this cancer.
The second study involving cannabinoids and pancreatic cancer was published in 2008 by a team of German researchers. The researchers used samples of human tissue instead of animal models, which were obtained from patients who underwent pancreatic surgery.
The study was able to confirm that cannabinoid receptors were overexpressed in pancreatic cancer cells, which suggests that activity of the endocannabinoid system may be upregulated in cases of pancreatic cancer. On the other hand, the researchers failed to identify higher levels of endocannabinoids – such as anandamide or 2-AG – in pancreatic tissue samples, although they speculated that local concentrations of endocannabinoids might still be altered.
The study also found an interesting correlation between cannabinoid receptors – specifically CB1 receptors – and pain. The results showed that patients with higher levels of CB1 receptors experienced less cancer-related pain, which is directly in line with evidence of the strong pain-reducing effects of medical marijuana. On the other hand, patients with higher levels of CB1 receptors also had lower rates of survival – a finding that the researchers had more difficulty explaining.
Overall, both studies concluded that research on cannabinoids in the treatment of pancreatic cancer shows promise and should be further pursued, despite largely unfounded fears of the negative side-effects associated with medical marijuana.
“…natural cannabinoids had been used by many societies until their prohibition at the beginning of the last century due to their addictive potential. However, the potential for addiction and psychotropic side effects seems to be by far overestimated, especially for patients with malignant tumors, for whom pain control, stable weight and quality of life are the main measures of medical therapy.”
“In conclusion, results presented here show that cannabinoids exert a remarkable antitumoral effect on pancreatic cancer cells in vitro and in vivo due to their ability to selectively induce apoptosis of these cells… These findings may help to set the basis for a new therapeutic approach for the treatment of this deadly disease.”