Medical cannabis is comparatively well established in cancer treatment: Cannabinoids relieve pain, nausea, and loss of appetite. Recent studies also suggest that pharmaceutical cannabis may be helpful in combating tumor diseases.
Cancer incidence in Europe: facts and figures
Cancer is one of the most common diagnoses in Western societies: every year, around 2.7 million people in the European Union develop cancer, and an estimated 1.4 million sufferers die from it. The trend is rising due to the aging population. The most common tumor disease in men is prostate cancer, followed by colon and lung cancer. In women, breast cancer is diagnosed most frequently, followed by lung and colon cancer. In many cases, cancer survival depends on the timing of detection.
In general, the earlier a cancer is detected and treated, the better the prognosis. In addition, the chances of cure differ for certain types of cancer .
How is cancer treated?
The therapy of a tumor disease is very individual and depends on the type of cancer, the localization of the tumor, the course of the disease as well as the general condition of the affected person. A so-called curative cancer therapy always has the goal of curing the patient.
The most important treatment options for cancer:
- Radiation therapy
- (Anti-) hormone therapy
- Bone marrow or stem cell therapy
- Antibody therapy/immunotherapy
- Special drugs against tumor cells
How do cannabinoids help with cancer?
Medical cannabis is already regularly used in cancer therapy. One of its main uses is to relieve tumor pain as well as side effects of chemotherapy such as vomiting, loss of appetite, and sleep disturbances .
A recent study from Israel showed that the “total burden of cancer symptoms” was reduced after six months of therapy with cannabinoids.
The cancer patients involved in the study reported both reduced pain symptoms and a reduced need for opiates, nonsteroidal analgesics, or antidepressants. Sufficiently long therapy with pharmaceutical cannabis, in this case in the form of well-tolerated cannabis oils, seems to be important .
Overview: Cannabis in breast cancer
An anonymous online survey from the USA shows how widespread (self-)therapy with cannabis already is among breast cancer patients: 42 percent of a total of 612 breast cancer patients regularly used cannabis to relieve their symptoms such as pain, insomnia, anxiety, stress, and nausea and vomiting .
The majority of participants used cannabinoids during acute cancer treatment – mostly in the form of cannabis-containing edibles, liquid tinctures (liquids), or smoked or vaporized cannabis flowers.
Alarming: cannabis often obtained via unsafe or illegal sources
Rather critical is the high procurement of cannabis via unregulated sources such as the black market, family, or friends. In addition, many of those affected lack reputable sources of information: Only twelve persons sought medical advice on the use of cannabis for therapeutic purposes.
It is also interesting to note that almost half of the respondents believe that cannabinoids not only relieve unpleasant symptoms, but also have a causal effect on their disease.
Can pharmaceutical cannabis fight cancer?
Preclinical studies on animals and cancer cells suggest that cannabinoids can indeed fight cancer, i.e., act as anticarcinogens. For example, THC and CBD appear to enhance the effects of anticancer drugs (cytostatics) .
Similar evidence is provided by a study from the United Kingdom published in 2021: it was observed that CBD and the cytostatic drug temozolomide enhanced each other in the treatment of patients with recurrent glioblastoma (malignant brain tumor). As a result, the one-year survival rate was higher in the study group treated with the two agents than in the placebo group .
Medical cannabis helps cancer patients on multiple levels. While cannabinoid therapy to alleviate the unpleasant side effects of chemotherapy is already well established, research on the causal treatment of tumor diseases is still in its infancy. However, recent studies point to the anticarcinogenic potential of pharmaceutical cannabis.
The procurement of cannabis through unregulated sources such as the black market is widespread. Therefore, better education of patients and their caregivers is important.
 Bundesministerium für Gesundheit. (2023, January 23). Krebs. https://www.bundesgesundheitsministerium.de/themen/praevention/gesundheitsgefahren/krebs.
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