Ask an answerable question (PICO)：
Radiation dermatitis (RD) is one of the common side effects of radiation therapy for breast cancer patients. It not only causes skin damage but also results in discomfort, which significantly affects the patients’ quality of life. Therefore, the prevention of radiation dermatitis is an important issue. In clinical practice, creams and petroleum jelly are used to prevent the incidence of radiation dermatitis. Calendula officinalis, a commonly seen medicinal plant in Taiwan, is known for its high safety and accessibility. Thus, this study employs an empirical approach to further investigate the preventive effects of Calendula officinalis cream on radiation dermatitis.
The Method and Analysis of Literature Review：
Formulation of PICO question based on the empirical steps. Does the use of Calendula officinalis cream in breast cancer patients undergoing radiation therapy lead to lower in the incidence of radiation dermatitis and pain compared to other ointments?. Medical Subject Heading (MeSH term) and natural language (free-text) were employed. In this study, the “P” was breast cancer patients receiving radiation therapy, the “I” was Calendula officinal or Marigold or Potmarigold, and the “O” was the incidence rate of radiation dermatitis and pain. Electronic databases including Cochrane Library, PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, and Airiti Library were searched, with the literature search conducted up until December, 2022. Inclusion criteria encompassed randomized controlled trial articles in English, while duplicated and articles not aligning with the PICO framework in terms of subject and abstract were excluded. Ultimately, three randomized controlled were selected for quality appraisal and a meta-analysis was conducted using Review manage 5.4 software.
Critical Appraisal：
Literature analysis and evidence grading according to CASP (Critical Appraisal Skills Programme) 2020 Randomized Controlled Trial Standard Checklist, as well as The Oxford 2011 Level of Evidence from the Oxford Centre for Evidence-Based Medicine, were conducted. Three articles, with a combined of 746 breast cancer patients who undergoing radiation therapy were included. The evidence level was classified as Level 2. The CASP checklist items satisfied ranged from 5 to 11, indication a moderated quality of evidence. The risk of bias was determined to be low, and the recommendation level was categorized Grade B. The integrated results revealed that the application of Calendula officinalis cream on breast cancer patients undergoing radiation therapy did not show statistically significant difference in the incidence rate of Grade 2 or higher radiation dermatitis according to the Radiation Therapy Oncology Group (RTOG) classification when compared to other creams (p =.43). Significant pain reduction was observed in only one of the three studies, while the remaining two studies did not reach statistical significance. Due to lack of consistent evidence, conclusion recommendations for use cannot be provided.
Results, Conclusions and Recommendations：
Synthesizing the results of the three randomized trials, it was found that the application of Calendula officinalis cream on breast cancer patients undergoing radiation therapy did not exhibit statistically significant differences in the prevention of Grader 2 or higher radiation dermatitis occurrence and pain when compared to three ethanolamine cream or Essex moisturizing cream and moisturizing lotion with glycerol. The evidence level for all three RCTS was categorized as Level 2 with a low risk of bias, and a recommendation strength of Grade B, suggesting against routine use. Additionally, there is insufficient evidence to support the use of 5-10% Calendula officinalis cream as a preventive intervention for radiation dermatitis in breast cancer patients. Further rigorous research designs are needed to confirm the preventive effects of Calendula officinalis cream on radiation dermatitis in patients with other cancers who undergoing radiation therapy.
林采蓉 沈桂芬 
