Controversial Link between Cannabis and Anticancer Treatments-Where Are We and Where Are We Going? A Systematic Review of the Literature

Surgery-Related Considerations in Treating People Who Use Cannabis: A Review

Importance

Cannabis use has experienced substantial growth. Many patients treated by otolaryngologists are using cannabis in various forms, often without the knowledge of the treating surgeon. These cannabinoid substances have various systemic effects, and it is critical for otolaryngologists to recognize how cannabis use may contribute to a patient's care.

Observations

Cannabis use has effects that contribute to every phase of a surgeon's care. Preoperative counseling for tapering use may prevent increased rates of adverse effects. Care with anesthesia must be observed due to increased rates of myocardial ischemia, higher tolerance to standard doses, and prolonged sedation. Although results of studies are mixed, there may be an association with cannabis use and postoperative pain, nausea, and vomiting. Postoperative wound healing may be improved through the use of topical cannabinoids. Significant drug-drug interactions exist with cannabis, most notably with several common anticoagulant medications. Care should be exercised when managing medications for people who use cannabis. While many people who use cannabis consume it infrequently, a substantial population has developed cannabis use disorder, which is associated with increased morbidity and mortality postoperatively. Screening for cannabis use disorder is important and can be done through short screening tools.

Conclusions and Relevance

Patients who use cannabis may require special attention regarding preoperative counseling and workup, intraoperative anesthesia, postoperative pain management, nausea, wound healing, and drug-drug interactions. As patient use continues to increase, otolaryngologists will find an increasing need to remain up to date on how cannabis use contributes to patient care.

Cannabis use and patient-reported outcomes among patients at a comprehensive cancer center

BACKGROUND

Patients with cancer report increasing rates of cannabis use, often to manage symptoms and toxicities. The efficacy and safety of cannabis, however, for some use cases remains unclear. To better understand characteristics of patients with cancer who report using cannabis, we examined data from a cannabis use survey of among patients with cancer seen at a National Cancer Institute-Designated Cancer Center.

METHODS

In late 2021, patients with cancer (N = 1608) treated between July 2017 and December 2019 provided cannabis use data. Additional data were obtained from medical records data and routine patient-reported outcomes collected for clinical purposes. Univariable analyses and multivariable regression analyses were conducted to identify correlates of cannabis use at different stages in the cancer care trajectory.

RESULTS

Rates of self-reported cannabis use by patients with cancer were 59% before cancer diagnosis and 47% after diagnosis. Longitudinal rates of cannabis use were 29% for no cannabis use, 23% before diagnosis, 12% after diagnosis, and 35% for both before and after diagnosis. Demographic factors associated with cannabis use included age, sex, race, and educational achievement. Tobacco use and binge drinking were associated with higher odds of cannabis use. Cannabis use was also associated with greater self-reported interference with physical functioning due to pain and interference with social functioning due to health problems.

CONCLUSIONS

We found high rates of cannabis use among patients with cancer, both before and after their cancer diagnosis. Future studies should further investigate psychosocial factors associated with cannabis use among patients with cancer as well as psychosocial outcomes among patients with cancer using cannabis.

Cannabis and Cannabinoids in Adults With Cancer: ASCO Guideline

PURPOSE

To guide clinicians, adults with cancer, caregivers, researchers, and oncology institutions on the medical use of cannabis and cannabinoids, including synthetic cannabinoids and herbal cannabis derivatives; single, purified cannabinoids; combinations of cannabis ingredients; and full-spectrum cannabis.

METHODS

A systematic literature review identified systematic reviews, randomized controlled trials (RCTs), and cohort studies on the efficacy and safety of cannabis and cannabinoids when used by adults with cancer. Outcomes of interest included antineoplastic effects, cancer treatment toxicity, symptoms, and quality of life. PubMed and the Cochrane Library were searched from database inception to January 27, 2023. ASCO convened an Expert Panel to review the evidence and formulate recommendations.

RESULTS

The evidence base consisted of 13 systematic reviews and five additional primary studies (four RCTs and one cohort study). The certainty of evidence for most outcomes was low or very low.

RECOMMENDATIONS

Cannabis and/or cannabinoid access and use by adults with cancer has outpaced the science supporting their clinical use. This guideline provides strategies for open, nonjudgmental communication between clinicians and adults with cancer about the use of cannabis and/or cannabinoids. Clinicians should recommend against using cannabis or cannabinoids as a cancer-directed treatment unless within the context of a clinical trial. Cannabis and/or cannabinoids may improve refractory, chemotherapy-induced nausea and vomiting when added to guideline-concordant antiemetic regimens. Whether cannabis and/or cannabinoids can improve other supportive care outcomes remains uncertain. This guideline also highlights the critical need for more cannabis and/or cannabinoid research.Additional information is available at www.asco.org/supportive-care-guidelines.

Pain management for post-treatment survivors of complex cancers: a qualitative study of opioids and cannabis

Aim: We aimed to understand experiences with opioids and cannabis for post-treatment cancer survivors. Patients & methods: We conducted seven focus groups among head and neck and lung cancer survivors, using standard qualitative methodology to explore themes around 1) post-treatment pain and 2) utilization, perceived benefits and perceived harms of cannabis and opioids. Results & conclusion: Survivors (N = 25) experienced addiction fears, stigma and access challenges for both products. Opioids were often perceived as critical for severe pain. Cannabis reduced pain and anxiety for many survivors, suggesting that anxiety screening, as recommended in guidelines, would improve traditional pain assessment. Opioids and cannabis present complex harms and benefits for post-treatment survivors who must balance pain management and minimizing side effects.

Tetrahydrocannabinol and Cannabidiol for Pain Treatment-An Update on the Evidence

In light of the current International Association for the Study of Pain (IASP) clinical practice guidelines (CPGs) and the European Society for Medical Oncology (ESMO) guidelines, the topic of cannabinoids in relation to pain remains controversial, with insufficient research presently available. Cannabinoids are an attractive pain management option due to their synergistic effects when administered with opioids, thereby also limiting the extent of respiratory depression. On their own, however, cannabinoids have been shown to have the potential to relieve specific subtypes of chronic pain in adults, although controversies remain. Among these subtypes are neuropathic, musculoskeletal, cancer, and geriatric pain. Another interesting feature is their effectiveness in chemotherapy-induced peripheral neuropathy (CIPN). Analgesic benefits are hypothesized to extend to HIV-associated neuropathic pain, as well as to lower back pain in the elderly. The aim of this article is to provide an up-to-date review of the existing preclinical as well as clinical studies, along with relevant systematic reviews addressing the roles of various types of cannabinoids in neuropathic pain settings. The impact of cannabinoids in chronic cancer pain and in non-cancer conditions, such as multiple sclerosis and headaches, are all discussed, as well as novel techniques of administration and relevant mechanisms of action.

Cannabinoids in anesthesia and chronic pain: Where do we stand?

Cannabis derivatives have been conventionally employed globally for their curative and restorative properties for various ailments. However, its recreational use and consequent legal restrictions have substantially cramped its scientific research. An emerging interest regarding the profound therapeutic potential of cannabinoids has been observed among clinicians. Despite a rich cultural background, high-quality research on cannabinoids is lacking in the Indian scenario. This review readdresses the challenges on this front and brings an insight into the current status of cannabinoids and their utility in scientific exploration. Cannabinoids have a significant medicinal value in various clinical disorders. Its use so far has been based on scarce resources and corroborations, as evidence-based substantiation is limited. Through this review article, we emphasize the remarkable role enacted by cannabinoids in the treatment of various clinical disorders and an utterly significant need to formulate stringent research methodologies to promote its systematic investigation.

Cannabis Use among Cancer Survivors: Use Pattern, Product Type, and Timing of Use

Despite growing interest in the use of cannabis for the treatment of cancer-related symptoms, there are limited studies that have assessed the use pattern, type, and mode of delivery of cannabis products used by cancer survivors. This study describes the current state of the use pattern, product type, and mode of delivery of cannabis used by cancer survivors. This was a cross-sectional study of cancer survivors from 41 U.S. states who received treatment at the largest NCI-designated comprehensive cancer center. The weighted prevalence of the use patterns, product types, and modes of delivery of cannabis used by cancer survivors was estimated. A total of 1886 cancer survivors were included in the study, with 915 (48% [95% CI: 45-51]) reporting ever using cannabis. Of survivors who had ever used cannabis, 36% (95% CI: 33-40) were current users. Among survivors who reported cannabis use after diagnosis, 40% used cannabis during and after cancer treatment, 35% used cannabis during treatment, and 25% used cannabis after completing their cancer treatment. Additionally, 48% of survivors reported an increase in cannabis use since cancer diagnosis. The commonest types of cannabis products used by cancer survivors were dry leaf cannabis (71%), cannabidiol (CBD) oil (46%), and cannabis candy (40%). Moreover, cancer survivors frequently used baked goods (32%), creams and gels (21%), and tinctures (18%). Furthermore, among ever users, the predominant mode of use was cannabis inhalation/smoking (69%) compared to eating/drinking (59%). More so, the common mode of inhalation/smoking of cannabis products were rolled cannabis cigarettes (79%), pipes (36%), water pipes (34%), vaporizers or vapes (14%), and e-cigarette devices (14%). A substantial number of cancer survivors use cannabis during cancer treatment, with increased use following cancer diagnosis. The forms and modes of delivery of cannabis varied among survivors, with most survivors inhaling or smoking cannabis. There is a need to educate healthcare providers (HCPs) and survivors on current evidence of cannabis use and strengthen cannabis regulatory frameworks to optimize benefits and minimize adverse events from cannabis use during cancer treatment.

Cannabinoids as multifaceted compounds

Since ancient times, Cannabis and its preparations have found various applications such as for medical, recreational and industrial purposes. Subsequently the 1930s, legislation in many countries has restricted its use due to its psychotropic properties. More recently, the discovery of endocannabinoid system, including new receptors, ligands, and mediators, its role in maintaining the homeostasis of the human body and the possible implication in various physiological and pathophysiological processes has also been understood. Based on this evidence, researchers were able to develop new therapeutic targets for the treatment of various pathological disorders. For this purpose, Cannabis and cannabinoids were subjected for the evaluation of their pharmacological activities. The renewed interest in the medical use of cannabis for its potential therapeutic application has prompted legislators to take action to regulate the safe use of cannabis and products containing cannabinoids. However, each country has an enormous heterogeneity in the regulation of laws. Here, we are pleased to show a general and prevailing overview of the findings regarding cannabinoids and the multiple research fields such as chemistry, phytochemistry, pharmacology and analytics in which they are involved.