Williams, M. S., Burk, M., Loprinzi, C. L., Hill, M., Schomberg, P.J., Nearhood, K., … Eggleston, W. D. (1996). Phase III double-blind evaluation of an aloe vera gel as a prophylactic agent for radiation-induced skin toxicity. International Journal of Radiation Oncology, Biology, Physics, 36, 345–349.

To determine if aloe vera gel can prevent the development of radiodermatitis in patients undergoing breast radiation therapy (RT).

In both studies, gels were applied twice a day starting within three days of RT initiation. Each patient received instruction on skin care. Patients were stratified by age groups:  younger than 45 years, 45 to 60 years, and older than 60 years.

• Study 1 included 194 patients.  
• Study 2 included 108 patients. 
• Patients were younger than 45 years (21.5%), 45 to 60 years (35%), or older than 60 years (43.5%). 
• All patients were women. 
• Patients had breast cancer.
• Patients were not receiving concomitant chemotherapy, and there were no scars or ulcers in the treatment field.

Two studies were reported:  a randomized, double-blind, controlled trial of aloe versus placebo gel and a randomized trial of aloe versus no treatment.

• Patients were rated by an MD/RN on scale of 0 (normal) to 3 (moist desquamation and/or ulceration).
• Patients self-rated on the same scale and completed questionnaires at the start and weekly until one month post RT. 
• Kaplan-Meier curves and log rank test were used to compare treatment arms.
• Severity scores were compared using Wilcoxon test.
• Spearman rank correlation coefficients were calculated to compare maximum severity.

• Study 1:  Mean severity score in aloe versus placebo gel was 1.9 and 1.9 by patient judgment. Mean severity score in aloe versus placebo gel was 1.5 versus 1.6 as judged by a healthcare provider. No significance was found.
• Study 2: Mean severity score in aloe versus no treatment was 1.9 versus 2 by patient judgment. Mean severity score in aloe versus no treatment was 1.7 versus 1.5 as judged by a healthcare provider. No significance was found.

The study does not support the hypothesis that aloe vera gel can decrease RT-induced dermatitis.

• The study lacked interrater reliability.
• The study did not use a valid or reliable scale.
• Patients were able to use other treatments, such as hydrocortisone or domeboro if they had skin problems, so it is not clear if confounding treatments were given.
• No skin care regimen log was used to determine adherence.