A case of long-term survival of metastatic desmoplastic small round cell tumor treated with multimodal therapy.

Desmoplastic small round cell tumor (DSRCT) is a rare, aggressive and malignant tumor that predominantly affects young males. No standard therapy is currently available for patients with DSRCT and the prognosis remains extremely poor. In this study, we report a thought-provoking DSRCT case. A 24-year-old male was admitted to our hospital with a chief complaint of hematemesis. Computed tomography revealed a retrovesical mass with a splenic hilar tumor, multiple lung and liver tumors and marked lymph node swellings. The source of hematemesis was gastric varices caused by the compression of the splenic vein by a splenic hilar tumor. The patient was provided with a histological diagnosis of DSRCT based on needle biopsy from the liver tumors and the pelvic mass was thought to be the primary lesion. This is a long-term survival case of metastatic DSRCT treated with multimodal therapy including 15 courses of multiagent chemotherapy, radiation therapy for the hepatic portal region using 42.5 Gy, and four instances of therapeutic endoscopy. The prolonged progression-free survival period (15 months) obtained following chemotherapy suggests the chemosensitive feature of the disease. We used a modified P6 regimen (cyclophosphamide, pirarubicin, vincristine, ifosfamide and etoposide) and a modified PAVEP regimen (cyclophosphamide, pirarubicin, etoposide and cisplatin) to decrease severe adverse events and to improve the completion rate of chemotherapy. DSRCT is an aggressive but chemo-sensitive disease, and continuous chemotherapy using an appropriate regimen with possible supportive care is essential for long-term survival. This case report may represent a treatment option for this rare disease.