Schneider, F., Danski, M.T., & Vayego, S.A. (2015). Usage of Calendula officinalis in the prevention and treatment of radiodermatitis: A randomized double-blind controlled clinical trial. Revista da Escola de Enfermagem da USP, 49, 221–228. 

To compare Calendula officinalis with essential fatty acids (EFAs) for the prevention and treatment of radiodermatitis among people with head and neck cancers

• Active control arm: EFAs
• Experimental arm: Calendula officinalis
• A pharmacy compounded the treatments and placed them in bottles.
• Radiation oncology nurses applied 10 ml of treatment on gauze after radiation therapy. Participants reapplied treatment 12 hours later.

• N = 51 total, n = 27 (control), n = 24 (Calendula)  
• MEAN AGE: EFA group: 60.44 years (SD = 10.53), Calendula group: 62.38 years (SD = 12.71)
• MALES (%): Not reported, FEMALES (%): Not reported, but the study included males and females. Most participants were male.
• KEY DISEASE CHARACTERISTICS: Head and neck cancers
• OTHER KEY SAMPLE CHARACTERISTICS: All patients were treated with Colbalt-60.

• SITE: Single site    
• SETTING TYPE: Not specified    
• LOCATION: Radiotherapy department, Curitiba, Parana, Brazil

PHASE OF CARE: Active antitumor treatment

Prospective, random assignment, double-blind, controlled clinical trial

Radiation Therapy Oncology Group (RTOG) scale for skin toxicity

The proportion of grade 2 radiodermatitis was significantly higher in the EFA group ascompared to the Calendula group (p = 0.012). The EFA group’s Kaplan-Meier survival curve was consistently lower (i.e., fewer survivors) than the Calendula group curve at every point of the survival curve (p = 0.00402). In patients receiving concurrent chemo/radiation therapy, grade 2 dermatitis was more frequent in the EFA group, with grade 1 dermatitis more frequent in the Calendula group (p = 0.0179).

Calendula was more efficacious than EFAs for the prevention and treatment of radiation-induced skin toxicity among individuals with head and neck cancers.

• Small sample (< 100)
• Risk of bias (sample characteristics)
• Measurement/methods not well described
• Findings not generalizable
• Subject withdrawals ≥ 10%
• The authors did not provide a table listing the demographics of the sample.
• The participants in the EFA arm were more likely to be orally fed than those in the Calendula arm (92.59% versus 70.83%).
• The authors reported using chi-square, the Fisher and G Williams test for categorical variables, and Mann-Whitney U and Wilcoxin tests for quantitative variables. However, the authors reported numerous percentages, a few p values, and a Kaplan-Meier curve in the article.
• The authors used “a team of trained researchers” but did not address inter-rater reliability.
• The control product (EFAs: sunflower oil, 1% vitamin A, 0.2% vitamin E, and 5% caprylic acid) and the experimental product (Calendula: 4% Calendula oil, 1% vitamin A, and liquid Vaseline) were compounded by the hospital pharmacy. This helped maintain double-blinding but made it more difficult to compare these results with studies conducted by Pommier (2004) and Sharp (2013) because the Calendula products differ in each of the studies.
• More than 50% of the control group and 42% of the experimental group members withdrew before the end of the study.

These results neither negate nor support the current Oncology Nursing Society's Putting Evidence into Practice (PEP) guidelines for the use of Calendula in radiodermatitis.