Assessing Benefits and Harms of Medical Cannabis and Cannabinoid Use in Breast Cancer Patients During and After Treatments

Breast cancer patients represent fast-growing medical cannabis and cannabinoid (MCC) users in this country; a recent survey indicates that about 42% of breast cancer patients use MCC to alleviate treatment-related symptoms, and many of these patients do not discuss their use with their oncologists. Despite being considered safe and well-tolerated, MCC may result in potential interactions with cancer treatments, adverse reactions, and tumor progression. Unfortunately, despite the increase in MCC use, research on its health effects, including the potential benefits and harms, remains limited. Therefore, we propose a prospective cohort study of breast cancer patients to address gaps in knowledge and build evidence of the types of products in use, frequency, dosage of use, and the benefits and harms of MCC use during and after cancer treatment. Our central hypothesis is that MCC may improve treatment-related symptoms and clinical outcomes in some patients by targeting the inflammasome/inflammatory pathway. Therapeutic strategies targeting inflammasome may prevent treatment-related symptoms and improve clinical outcomes. We will test a new paradigm that the inhibition of inflammasome-mediated inflammatory responses by MCC plays a role in its biological effects. We plan to enroll 600 breast cancer patients (300 MCC users and 300 non-MCC users) and collect data on patient characteristics, treatment plans, clinician-reported outcomes, adverse reactions, and patient-reported outcomes. We will monitor MCC use through in-person visits and technology-based assessments such as smartphone and sensor-based measurement bursts. We will also collect blood samples for MCC quantitation/characterization and inflammasome/inflammatory biomarkers. Aim 1 will evaluate the benefits and harms of MCC in breast cancer patients during and after treatment. Aim 2 will elucidate whether inflammasome/inflammatory biomarkers mediate the benefits and harms of MCC in breast cancer therapies and other medications used. Aim 3 will investigate how MCC product characteristics impact benefits and harms (Aim 1) and inflammasome and inflammatory biomarkers (Aim 2). Leveraging our promising preliminary data, state-of-the-art high-throughput technologies, and a multidisciplinary research team with complementary expertise, we are well-positioned to conduct this study and address the scientific knowledge gaps surrounding the benefits and harms of MCC in breast cancer patients. We will provide scientific evidence on the impact of MCC on breast cancer patients during and after treatments, the biological effects of MCC during treatments, potential interactions between MCC and cancer therapies and other medications, and the types and patterns of MCC use that present the best benefits/harms ratio. Our results will be of great value to physicians and cancer patients, as they will inform decision-making regarding MCC to enhance therapies, improve quality of life, and minimize adverse effects. If funded, we will work closely with the coordinating center and NCI in sharing assessment measures and disseminating study findings.