Desmoplastic Small Round Cell Tumor Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: Results of a Phase 2 Trial

Desmoplastic small round cell tumor (DSRCT) is a rare sarcoma that primarily affects adolescents and young adults. Patients can present with many peritoneal implants. We conducted a phase 2 clinical trial utilizing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) with cisplatin for DSRCT and pediatric-type abdominal sarcomas. A prospective cohort study was performed on 20 patients, who underwent CRS-HIPEC procedures, with cisplatin from 2012 to 2013. All patients were enrolled in the phase 2 clinical trial. Patients with extraabdominal disease and in whom complete cytoreduction (CCR0-1) could not be achieved were excluded. All outcomes were recorded. Fourteen patients had DSRCT, while five patients had other sarcomas. One patient had repeat HIPEC. Patients with DSRCT had significantly longer median overall survival after surgery than patients with other tumors (44.3 vs. 12.5 months, p = 0.0013). The 3-year overall survival from time of diagnosis for DSRCT patients was 79 %. Estimated median recurrence-free survival (RFS) was 14.0 months. However, RFS for patients with DSRCT was significantly longer than for non-DSRCT patients (14.9 vs. 4.5 months, p = 0.0012). Among DSRCT patients, those without hepatic or portal metastases had longer median RFS than those with tumors at these sites (37.9 vs. 14.3 months, p = 0.02). In 100 % of patients without hepatic or portal metastasis, there was no peritoneal disease recurrence after CRS-HIPEC. Complete CRS-HIPEC with cisplatin is effective in select DSRCT patients. DSRCT patients with hepatic or portal metastasis have poorer outcomes.