The use of complementary and integrative therapies as adjunct interventions during radiotherapy: a systematic review

Literature supporting the efficacy of complementary and integrative medicine (CIM) alongside radiotherapy is fragmented with varying outcomes and levels of evidence. This review summarizes the available evidence on CIM used with radiotherapy in order to inform clinicians. A systematic literature review identified studies on the use of CIM during radiotherapy. Inclusion required the following criteria: the study was interventional, CIM therapy was for human patients with cancer, and CIM therapy was administered concurrently with radiotherapy. Data points of interest were collected from included studies. A subset was identified as high-quality using the Jadad scale. Fisher’s exact test was used to assess the association between study results, outcome measured, and type of CIM. Overall, 163 articles met inclusion. Of these, 68 (41.7%) were considered high-quality trials. Articles published per year increased over time (p < 0.01). Frequently identified therapies were biologically based therapies (47.9%), mind-body therapies (23.3%), and alternative medical systems (13.5%). Within the subset of high-quality trials, 60.0% of studies reported a favorable change with CIM while 40.0% reported no change. No studies reported an unfavorable change. Commonly assessed outcome types were patient-reported (41.1%) and provider-reported (21.5%). Rate of favorable change did not differ based on type of CIM (p = 0.90) or outcome measured (p = 0.24). Concurrent CIM may reduce radiotherapy-induced toxicities and improve quality of life, suggesting that physicians should discuss CIM with patients receiving radiotherapy. This review provides a broad overview of investigations on CIM use during radiotherapy and can inform how radiation oncologists advise their patients about CIM.