• condrosarcoma mesenchimale
• chemioterapia
• sarcoma

MCS is an ultra-rare sarcoma marked by the presence of HEY1-NCOA2 fusion and characterized by a poor prognosis in the advanced phase. Data on the activity of systemic agents in mesenchymal chondrosarcoma (MCS) are only retrospective and limited to case reports or small and heterogeneous series. They
report a median progression-free survival (m-PFS) to anthracycline-based regimens of approximately 6 months, while a longer disease control was seen in the 3 patients (pts) from different series treated with trabectedin. This is to report on the results of an Italian, multicentric, retrospective study of the activity of cytotoxic chemotherapy in pts affected by MCS.
Pts of any age with a centrally reviewed pathological diagnosis of MCS treated with anthracycline-based regimens and/or high-dose ifosfamide and/or trabectedin within the Italian Sarcoma Group centers between 2000 and 2022 were retrospectively reviewed. Response was assessed retrospectively by a dedicated radiologist of each participating center by RECIST v1.1. PFS and overall survival (OS) were estimated by Kaplan-Meier method.
Duration of response (DoR) was calculated from the date of best response to the date of first evidence of progression for pts with complete response (CR) and partial response (PR).
Our retrospective study confirmed that anthracycline-based regimens are active in MCS with a m-PFS of 7 months in the advanced phase.
Trabectedin, although with no dimensional responses and in a small number of cases, obtained a prolonged disease control. On this basis, a confirmatory phase II single arm trial with trabectedin in mesenchymal chondrosarcoma is just started within the Italian Sarcoma Group.