Intraabdominal desmoplastic small round cell tumor: results of ifosfamide-based chemotherapy

Intraabdominal desmoplastic small round cell tumor (IDSRT) is a rare neoplasm, which is malignant and typically occurs in young adults. Although IDSRT is chemotherapy-sensitive, most cases do not achieve a complete response (CR). Even if some cases achieve a CR, they often relapse and result in poor prognosis. We report two cases of IDSRT, in a 24-year-old man and a 23-year-old man, who were treated with ifosfamide-based chemotherapy. Case 1, a 24-year-old man, presented with an abdominal mass, and the diagnosis of the biopsy specimen at laparoscopy was IDSRT. He received 7 courses of ifosfamide-based chemotherapy, which obtained a partial response (PR). He had no surgical resection, except for the biopsy procedure, and he underwent a total of 21 courses of chemotherapy. He died 36 months after diagnosis because of tumor regrowth and peritoneal bleeding. Case 2, a 23-year-old man, whose biopsy material allowed a diagnosis of IDSRT, was treated with 18 courses of chemotherapy, using ifosfamide, that resulted in a PR. This was followed by resection of the abdominal lesions, and he received an additional 2 courses of adjuvant chemotherapy. Four months after, completion of these 2 courses, the tumor recurred, and he died of diffuse pulmonary metastasis 36 months after diagnosis. This case report examines the results of ifosfamide-based chemotherapy in our two patients.