Clinical Takeaway
Topical cannabis balms were tested in a randomized trial for postmenopausal breast cancer patients experiencing joint pain and stiffness caused by aromatase inhibitor therapy. The study evaluated whether this approach was practical and safe to use in this population. Results provide early evidence on whether cannabinoid-based topical treatments may help patients stay on their prescribed hormone-blocking medications by reducing musculoskeletal discomfort.
#16 A Randomized, Open-Label Trial to Assess Feasibility and Tolerability of Topical Cannabis Balms for the Treatment of Aromatase Inhibitor-Associated Musculoskeletal Syndrome (AIMSS).
Citation: Zylla Dylan et al.. A Randomized, Open-Label Trial to Assess Feasibility and Tolerability of Topical Cannabis Balms for the Treatment of Aromatase Inhibitor-Associated Musculoskeletal Syndrome (AIMSS).. Cannabis and cannabinoid research. 2026. PMID: 41467893.
Design: 5 Journal: 1 N: 0 Recency: 3 Pop: 2 Human: 1 Risk: -2
This study addresses a significant clinical gap by evaluating topical cannabis as a potential treatment for AIMSS, a prevalent adverse effect that compromises medication adherence in approximately two-thirds of women receiving adjuvant aromatase inhibitor therapy for breast cancer. Improved tolerability of AIs through cannabinoid-based interventions could enhance treatment compliance and ultimately improve oncologic outcomes in this patient population. The feasibility and safety data from this trial may establish a foundation for larger efficacy studies and inform clinical decision-making regarding symptom management in AI-treated breast cancer survivors.
Quality Gate Alerts:
- Preclinical only
Methodological Considerations:
- Open-label design — placebo effect not excluded
Abstract: INTRODUCTION: Aromatase inhibitors (AIs) are commonly used for postmenopausal women with hormone receptor-positive breast cancer. Nearly two-thirds of women on AIs have arthralgias, joint stiffness, and/or bone pains referred to as aromatase inhibitor-induced musculoskeletal syndrome (AIMSS), leading to poor adherence. Preclinical and clinical data suggest topical cannabinoids can reduce inflammation in arthritis. MATERIALS AND METHODS: We conducted a randomized trial assessing feasibility, tolerability, and preliminary efficacy of topical cannabis for women with stage 1-3 breast cancer experiencing AIMSS. Women were randomized 1:1 to cannabidiol (CBD) vs. delta-9-tetrahydrocannabinol (THC) balms. The balm was applied three times daily to hands for 2 weeks, followed by a 2-week extension with the balm of their choice. Modified Score for the Assessment and Quantification of Chronic Rheumatoid Affectations of the Hands (M-SACRAH), brief pain inventory, and skin toxicity measures were captured weekly. RESULTS: A total of 21 women completed the study over 14 months. The mean age was 54, 86% White, 43% received adjuvant chemotherapy, and 48% reported no lifetime cannabis use. Compliance was high, with 71% continuing an additional 2 weeks and 86% of weekly surveys completed. We found 86% of participants reported improvement in M-SACRAH from baseline to week 2 with a higher percentage of the THC balm group reporting a >50% improvement (50% vs. 18%). Minor skin irritation was reported by 24%, and one patient discontinued balm due to “greasy” texture. CONCLUSIONS: Conducting a randomized trial of topical cannabis using state-approved dispensaries is feasible. Both THC and CBD balms are well tolerated. Placebo-controlled trials are needed to determine if balms can reduce AIMSS severity in breast cancer survivors.
💊 This feasibility trial addresses a genuine clinical gap: nearly two-thirds of women on aromatase inhibitors experience significant musculoskeletal symptoms that compromise treatment adherence for their cancer therapy, and topical cannabinoids offer a theoretically rational approach given anti-inflammatory mechanisms in preclinical models. However, the open-label design without placebo control substantially limits our ability to distinguish genuine drug effects from expectancy effects, which are particularly potent in pain conditions, and the absence of standardized cannabinoid dosing and formulations across trial sites raises questions about generalizability and reproducibility. Additionally, we lack clarity on whether observed tolerability translates to meaningful symptom improvement or sustained medication adherence, and long-term safety data for topical cannabis in this population remains sparse. If future blinded, adequately powered trials demonstrate efficacy, topical cannabinoid balms could offer women with AIMSS a non-systemic option to manage symptoms while maintaining adherence to cancer therapy, but we should counsel patients that current evidence