Therapeutic results of a novel enzyme-targeting radiosensitization treatment, Kochi oxydol-radiation therapy for unresectable carcinomas II, in patients with stage I primary breast cancer.

Linac-based stereotactic radiotherapy has little effect on the majority of advanced neoplasms. Therefore, the novel radiosensitizer Kochi oxydol-radiation therapy for unresectable carcinomas (KORTUC) II, which contains hydrogen peroxide and sodium hyaluronate, was developed. The effectiveness of KORTUC II for the treatment of chemotherapy-resistant supraclavicular lymph node metastases, recurrent breast cancer and stage IV primary breast cancer has previously been demonstrated. The present study evaluated the safety and efficacy of KORTUC II for patients with stage I primary breast cancer. A total of 15 patients (age range, 40-76 years) were enrolled. The injection of 3 ml of KORTUC II agent was initiated from the sixth radiotherapy fraction and was performed twice a week, under ultrasonographic guidance. The therapeutic effects were evaluated by PET-CT and/or MRI examinations prior to and following KORTUC II treatment. All patients exhibited complete responses and the overall survival rate was 100% after a follow-up period of five years. The mean duration of follow-up at the end of March 2015 was 53 months. Based on these results, KORTUC II treatment exhibited marked therapeutic effects with satisfactory treatment outcomes and an acceptable extent of adverse events.