Impressive response and longterm survival in a patient with metastatic extraskeletal myxoid chondrosarcoma treated with radiotherapy and trabectedin: a synergistic activity

Abstract

The extraskeletal myxoid chondrosarcoma (EMC) is a rare malignant accounting for less than 3% of soft tissue tumors. EMC is considered an intermediate aggressive neoplasm with a slow-growing and indolent clinical course. Nevertheless, local recurrence is frequent and distant metastases arise in about 50%-90% of cases. For these patients therapeutic options are scarce due to the poorly sensitivity of EMC to cytotoxic chemotherapy and targeted therapy. We report the case of a caucasian adult man with bulky locoregional and mediastinal disease resistant to antracyclinbased chemotherapy and targeted therapy. Then, a third line chemotherapy with trabectedin was used obtaining temporary disease stabilization. Due to arising of symptoms and modest increase of lesions, radiotherapy was added with four consecutive treatments on right gluteal mass, large right and left paravertebral lesions, and mediastinal bulky disease, respectively. Rapidly, near complete regression of masses was noted. After 41 months from metastasis and 28 after beginning of chemotherapy with trabectedin and complementary radiotherapy, the patient is in good clinical conditions and the disease under control. In our experience, radiotherapy is a valid option in metastatic ECM and when associated with trabectedin a potent synergistic effect could be obtained.