High Efficacy of Preoperative Low-Dose Radiotherapy with Sanazole (AK-2123)‎ for Extraskeletal Ewing's Sarcoma: A Case Report

Abstract EN

Extraskeletal Ewing's sarcoma is a rare soft tissue tumor that is morphologically indistinguishable from Ewing's sarcoma of bone.

We report a case of extraskeletal Ewing's sarcoma with several systemic problems.

A 69-year-old man presented with a 5-month history of a rapidly enlarging mass in the right thigh.

Because preoperative radiotherapy with sanazole (AK-2123) contributed the tumor mass reduction down to 40% in size, the tumor was successfully resected with clear surgical margins and repaired with a musculocutaneous flap.

The high efficacy of pre-operative low-dose radiotherapy with sanazole was histologically confirmed that the resected tumor specimen involved no viable tumor cells and showed 100% necrosis.

Based on clinical outcomes in this case, the combined modality of pre-operative low-dose radiotherapy with hypoxic cell radiosensitizer and adequate surgical resection might provide for the useful clinical application of extraskeletal Ewing's sarcoma treatment.