Published online Jun 10, 2016. doi: 10.5306/wjco.v7.i3.275
Peer-review started: January 15, 2016
First decision: February 2, 2016
Revised: February 11, 2016
Accepted: March 22, 2016
Article in press: March 23, 2016
Published online: June 10, 2016
Processing time: 144 Days and 0.6 Hours
Curcumin is widely reported to have remarkable medicinal - and antineoplastic - properties. This review details curcumin’s relationship with radiotherapy (RT), principally as a radiosensitizer for various malignancies and a radioprotector for normal tissues. First, examples of radiosensitization are provided for various cancers: Pediatric, lymphoma, sarcoma, prostate, gynecologic, pancreas, liver, colorectal, breast, lung, head/neck, and glioma. It is not the purpose of this article to comprehensively review all radiosensitization data; however, high-quality studies are discussed in relationship to currently-controversial RT questions for many cancers, and thus the importance of developing a natural radiosensitizer. Attention is then shifted to radioprotection, for which supporting research is discussed for the following RT toxicities: Dermatitis, pneumonitis, cataractogenesis, neurocognition, myelosuppression, secondary malignancies, and mucositis/enteritis. Though there is fewer data for radioprotection, the overall quality of clinical evidence is higher, and small clinical trials implicating the efficacy of curcumin for RT toxicities (vs placebo/current therapies) are also detailed. Though the overall level of evidence for curcumin as a radiosensitizer and radioprotector is low, it must be recognized that risks of adverse effects are exceedingly low, and clinicians may need to judge the yet-unproven rewards with low toxicity risks.
Core tip: The Indian spice curcumin (turmeric) has been widely reported, largely in the preclinical realm, to offer many health - including antineoplastic - benefits. Though this article is not meant as a summative review of all studies of curcumin and radiotherapy, selected studies will be discussed that demonstrate curcumin to be a radiosensitizer of many types of tumor cells. Furthermore, data illustrating curcumin as a radioprotector of normal organs - including clinical studies - are also described. It is a sincere hope that these promising results can lead to curcumin use in cancer patients, either on or off a clinical protocol.