Lin, L. C., Que, J., Lin, L. K., & Lin, F. C. (2006). Zinc supplementation to improve mucositis and dermatitis in patients after radiotherapy for head-and-neck cancers: a double-blind, randomized study. International Journal of Radiation Oncology, Biology, Physics, 65, 745–750.

To determine whether zinc supplementation can accelerate the healing of mucositis and dermatitis after radiation therapy (RT).

There were two randomized groups:  the experimental (group A) received 25 mg of zinc three times per day and the control (group B) received the placebo (n = 48).

The principle researcher was blinded. Evaluation and grading of mucositis and dermatitis was performed weekly during treatment andtwo weeks after completion of RT, including the weekends.

• The sample was comprised of 97 patients (86% male, 14% female).
• Mean (standard deviation) age was 50 years (11 years) in group A and 51 years (11 years) in group B.
• Patients had head and neck cancer.
• The daily fraction was 180 t–200 cGy in five weekly fractions. Interruption was greater than three days.
• Of the patients, 59% were receiving concurrent chemotherapy.

Chi-Mei Foundation Medical Center Tainan, Taiwan, China

The study was a randomized, double-blind, placebo-controlled trial.

Radiation Therapy Oncology Group (RTOG) scores for dermatitis

• Group A had less interruption, and more patients completed treatment. Zinc supplementation use did not show much benefit in the patients who received concurrent chemotherapy.
• Survival curve analysis showed that grade 2 (p = 0.014) and grade 3 (p = 0.0092) dermatitis was less prevalent and occurred later in patients receiving zinc supplementation.
• No significant difference was found in the two weeks following treatment completion and resolution of dermatitis.

Oral zinc supplementation may delay the onset and reduce the severity of radiodermatitis.

The treatment design for the timing of the study was standard practice; it is not certain if one could correlate the study information to modern treatment delivery.