Intraabdominal desmoplastic small round cell tumor presenting as a gastric mural mass with hepatic metastases.

Purpose: An atypical case of childhood intraabdominal desmoplastic small round cell tumor (DSRCT) is presented.

Patient And Methods: An 11-year-old boy presented with progressive nausea and vomiting, abdominal pain, hepatomegaly, and an epigastric mass. Computed tomographic scanning as well as findings at gastroscopy and laparotomy revealed a large gastric mural tumor accompanied by multiple large intrahepatic masses. Histopathologic examination of biopsy samples revealed evidence of a polyphenotypic neoplasm diagnostic of DSRCT.

Results: Unlike most reported cases of DSRCT, no evidence of peritoneal involvement or ascites was detected. Despite an excellent initial response to multiagent chemotherapy, the patient eventually died of progressive tumor.

Conclusions: Though the radiographic and surgical findings in DSRCT usually suggest a mesenteric, peritoneal, or retroperitoneal site of tumor origin, this case demonstrates that intraabdominal DSRCT can present with a primary visceral lesion without evidence of peritoneal or mesenteric involvement or ascites. Combination chemotherapy using vincristine, doxorubicin, cyclophosphamide, cisplatin, and 5-fluorouracil may be of some benefit to patients with this rare tumor.