Phase II Study of the Effectiveness of the Germinated Wheat-derived Rigenase Plus Polyhexanide in the Prophylaxis for Hypofractionated Radiation-induced Acute Skin Toxicity in Breast Cancer

Background/Aim: To assess the efficacy of the wheat extract rigenase plus the antiseptic polyhexanide spray in preventing and reducing the incidence of grade 2-3 acute radiation-induced skin toxicity (RIST) in patients undergoing adjuvant hypo-fractionated radiotherapy to the breast for cancer.

Patients and Methods: Three hundred and twenty-four patients participated in this study, enrolled in 15 centers in Southern Italy. Rigenase/polyhexanide was applied twice a day, starting on the first day and ending two weeks post-radiotherapy. Patients underwent weekly skin assessments throughout radiotherapy and at 2-4 weeks after treatment. Outcome measures were assessed using the Common Toxicity Criteria of the National Cancer Institute RIST criteria.

Results: In most cases, RIST was observed after three weeks of radiotherapy. Grade 2 skin toxicity was recorded in 24% of patients, starting from week 2 with a peak at week 3. Grade 3 was observed starting from week 2 with a peak at week 3 where it was recorded in 4.5% of patients. The incidence of grade 2 and 3 progressively declined and disappeared by week 8. The median perceived benefit among patients and treating physicians differed significantly. All patients well tolerated treatment with rigenase/polyhexanide without meaningful side-effects. Twenty-one patients (0.06%) complained of light pruritus and two stopped rigenase/polyhexanide after 1 and 2 weeks.

Conclusion: Patients treated with adjuvant hypo-fractionated radiotherapy for breast cancer developed grade 2 RIST in slightly less than a quarter of cases with the use of rigenase/polyhexanide. No treatment delays or withdrawals were observed because of RIST. The tolerance was excellent.