Boron neutron capture therapy as new treatment for clear cell sarcoma: Trial on different animal model

•BNCT with the use of l-BPA was applied for three human clear cell sarcoma (CCS) cell lines.•BNCT trial was performed on a newly established intramuscularly CCS-bearing animal model.•A significant decrease of the tumor-volume was seen by single BNCT with the use of l-BPA.•A multiple BNCT application would be required for controlling the growth of any residual tumors.

Clear cell sarcoma (CCS) is a rare malignant tumor with a poor prognosis. In our previous study, the tumor disappeared under boron neutron capture therapy (BNCT) on subcutaneously-transplanted CCS-bearing animals. In the present study, the tumor disappeared under this therapy on model mice intramuscularly implanted with three different human CCS cells. BNCT led to the suppression of tumor-growth in each of the different model mice, suggesting its potentiality as an alternative to, or integrative option for, the treatment of CCS.