Mometasone furoate effect on acute skin toxicity in breast cancer patients receiving radiotherapy: a phase III double-blind, randomized trial from the North Central Cancer Treatment Group N06C4.

Purpose: A two-arm, double-blind, randomized trial was performed to evaluate the effect of 0.1% mometasone furoate (MMF) on acute skin-related toxicity in patients undergoing breast or chest wall radiotherapy.

Methods And Materials: Patients with ductal carcinoma in situ or invasive breast carcinoma who were undergoing external beam radiotherapy to the breast or chest wall were randomly assigned to apply 0.1% MMF or placebo cream daily. The primary study endpoint was the provider-assessed maximal grade of Common Terminology Criteria for Adverse Events, version 3.0, radiation dermatitis. The secondary endpoints included provider-assessed Common Terminology Criteria for Adverse Events Grade 3 or greater radiation dermatitis and adverse event monitoring. The patient-reported outcome measures included the Skindex-16, the Skin Toxicity Assessment Tool, a Symptom Experience Diary, and a quality-of-life self-assessment. An assessment was performed at baseline, weekly during radiotherapy, and for 2 weeks after radiotherapy.

Results: A total of 176 patients were enrolled between September 21, 2007, and December 7, 2007. The provider-assessed primary endpoint showed no difference in the mean maximum grade of radiation dermatitis by treatment arm (1.2 for MMF vs. 1.3 for placebo; p = .18). Common Terminology Criteria for Adverse Events toxicity was greater in the placebo group (p = .04), primarily from pruritus. For the patient-reported outcome measures, the maximum Skindex-16 score for the MMF group showed less itching (p = .008), less irritation (p = .01), less symptom persistence or recurrence (p = .02), and less annoyance with skin problems (p = .04). The group's maximal Skin Toxicity Assessment Tool score showed less burning sensation (p = .02) and less itching (p = .002).

Conclusion: Patients receiving daily MMF during radiotherapy might experience reduced acute skin toxicity compared with patients receiving placebo.