Complementary Medicine in Oncology: A Dual-Perspective Examination of Patient Use and Clinician Attitudes

Use of complementary and alternative medicine (CAM) among cancer patients has increased, yet limited research has examined how patient behaviors, clinician perspectives, and communication patterns intersect within the same clinical environment. This scoping review examines the prevalence and types of CAM used by cancer patients, evaluates oncologists' knowledge and attitudes toward CAM, and identifies communication factors shaping disclosure and clinical decision-making in conventional oncology care.

Following PRISMA-ScR guidelines, this review included peer-reviewed studies assessing CAM use among adult cancer patients, clinician perspectives, or patient-physician communication. Eligible studies included surveys, observational studies, systematic reviews, and clinical reports.

Included studies demonstrated that approximately 40% of cancer patients reported using CAM, with common modalities including herbal products, nutraceuticals, probiotics, and mind-body therapies. Non-disclosure rates varied considerably, with many patients refraining from discussing CAM use because of concerns about negative provider reactions or limited consultation time. On the clinician side, key barriers included limited formal training in CAM and uncertainty regarding the quality of supporting evidence. Evidence also demonstrated communication gaps and discordance between patient motivations and clinician concerns related to treatment safety and herb-drug interactions.

CAM use remains prevalent in oncology and is shaped by patient beliefs, cultural factors, and clinical communication. Variability in study methods and definitions limits cross-study comparisons. Enhancing clinician education, fostering open communication, and conducting institutional assessments may improve the safe and informed integration of CAM into oncology practice.