Matrixyl-containing Thêta-Cream shows no skin-protection advantage over dexpanthenol in breast radiotherapy

Breast cancer patients undergoing radiotherapy after breast-conserving surgery routinely develop acute radiation dermatitis, ranging from erythema and elevated skin temperature to desquamation. Standard prophylaxis relies on emollient agents such as dexpanthenol-containing lotions, but skin reactions remain a significant source of morbidity and treatment interruption. Thêta-Cream was proposed as an improved prophylactic formulation, combining CM Glucan, Hydroxyprolisilan C, and the palmitoyl peptide Matrixyl — ingredients purported to support skin-barrier integrity and modulate the inflammatory cascade. Phase II studies suggested the cream might reduce acute radiation side effects, prompting this direct head-to-head comparison against the established standard of care.

A prospective randomized study enrolled 20 breast cancer patients who had undergone breast-conserving surgery and were beginning adjuvant radiotherapy. Patients were randomized to apply either Thêta-Cream (containing CM Glucan, Hydroxyprolisilan C, and Matrixyl) or Bepanthol lotion (dexpanthenol) throughout their treatment course. Acute skin toxicity was assessed at 0, 30, and 50 Gy using a modified RTOG scoring system across defined skin areas of the breast. Secondary endpoints included patient satisfaction with the skin-care regimen (rated on a 0–10 scale), technical assistant ratings of skin mark quality, and blinded ranking of anonymized breast photographs at 50 Gy by independent investigators.

Across all individual toxicity parameters and their summed scores within defined breast skin areas, no differences in median or range were detected between the Thêta-Cream and Bepanthol groups. Maximum toxicity in both groups averaged moderate erythema, mild elevation of skin temperature, and no desquamation — outcomes that were statistically indistinguishable between arms.

Blinded independent ranking of anonymized breast photographs taken at 50 Gy confirmed that side effects were judged as equal between groups.

Noteworthy safety signals emerged exclusively in the Thêta-Cream arm: one suspected allergic reaction and two cases requiring resimulation (necessitating workflow interruption) were reported, with none occurring in the Bepanthol group. Mild itchiness and sporadic efflorescences were observed more frequently in Thêta-Cream users. Patient satisfaction was high in both groups, averaging 1.25 on a 0–10 scale (lower = better), indicating broad acceptability of either regimen. A trend toward worse skin marks — relevant for radiation targeting accuracy — was noted in Thêta-Cream users.