RESUMO
Desmoplastic small round-cell tumor is an uncommon, highly aggressive tumor with a predilection for pediatric age groups and young adults. It is very unusual in the elderly population. Although Agent Orange has been associated with soft-tissue sarcoma, an association with desmoplastic small round-cell tumor has not been reported. A 52-year-old male presented with abdominal distention, dyspnea, and a 9 kg weight loss. Prior history was significant for hepatitis C and diabetes. He was a Vietnam veteran and he admitted being exposed to Agent Orange. On physical examination, the abdomen was distended and tense. Computed tomography scan of the chest, abdomen and pelvis demonstrated extensive mediastinal and retroperitoneal adenopathy, diffuse omental masses and extensive pleural, intra-abdominal and pelvic ascites. Omental core needle biopsy was consistent with desmoplastic small round-cell tumor based on morphology and immunohistochemistry. He responded poorly to chemotherapy with high-dose cyclophosphamide, doxorubicin and vincristine and died 5 months after presentation secondary to neutropenic sepsis despite G-CSF support and antibiotics.