Radiotherapeutic bandage for the treatment of squamous cell carcinoma of the skin

Introduction: Squamous cell carcinoma (SCC) is the second most common form of skin cancer in the United States. The efficacy of a pharmaceutically elegant radiotherapeutic bandage, previously described by us for application against SCC of the skin, was tested for the first time in vivo using a subcutaneous SCC mouse model and a therapeutically relevant radiation dose. Methods: Female athymic nude mice were injected with human Colo-16 SCC cells subcutaneously and after eight days (average tumor volume: 35 ± 8.6 mm³) received no treatment, or were exposed to non-radioactive or radioactive (92.5 ± 18.5 MBq) bandages for approximately 1 h (n = 10 per group). After treatment, tumors were measured over fifteen days, tumor volume ratios (TVRs) compared and histopathology performed. Results: Fifteen days after treatment, the TVR of the radioactive bandage treatment group was 3.3 ± 4.5, while TVRs of the non-radioactive bandage treatment and no treatment control groups were 33.2 ± 14.7 and 26.9 ± 12.6, respectively. At the time of necropsy, there was mild focal epidermal hyperplasia surrounding a small area of epidermal ulceration in the radioactive bandage group. No other examined tissue (i.e., muscle, liver, kidney, lung, spleen and heart) showed significant lesions. Conclusions: Our radiotherapeutic bandage exhibits promising efficacy against SCC of the skin in a mouse model. It can be individually tailored for easy application on tumor lesions of all shapes and sizes, and could complement or possibly replace surgery in the clinic.