Complementary and alternative medicine and the risk of delayed diagnosis and treatment for cancer patients: a systematic review and meta-analysis

Complementary and alternative medicine (CAM) use is widespread among cancer patients, and has been linked to delayed conventional care, often leading to late-stage presentation. This study aimed to synthesize current evidence on the association between CAM use and delays in cancer diagnosis and treatment. The literature search using Pub- Med and Google Scholar with search terms “delay,” “diagnostic delay,” “treatment delay,” “complementary and alternative medicine,” and “cancer” was conducted. Included studies focused on assessing CAM use as a factor associated with diagnostic or treatment delay among cancer patients. It was found that the duration of diagnostic and treatment delays ranged from 14 days to 4 months. Herbal medicine and homeopathy were the most commonly reported CAM modalities. Pooled analysis showed that CAM use was associated with higher diagnostic delay [OR = 2.12 (95% CI 1.59–2.83)] and treatment delay [OR = 2.00 (95% CI 1.03–3.90)], but the small number of studies and patients limits the results of heterogeneity analysis. These findings highlight the need for healthcare providers to discuss CAM use with patients and to strengthen early detection and timely initiation of therapy.