Desmoplastic small round cell tumor is a very rare malignancy. We report the case of a 26-year-old woman who suffered from dyspepsia and abdominal pain for 2 months. We performed an endoscopic biopsy of the duodenal mass and diagnosed her disease as desmoplastic small round cell tumor using immunohistochemical staining, fluorescence in situ hybridization, and reverse transcriptase polymerase chain reaction. Because the mass invaded the pancreas and superior mesenteric vein as well as duodenum and the disease was disseminated to liver and peritoneum, she received palliative chemotherapy using vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide. The maximal response to chemotherapy was stable disease. The patient expired 9 months after diagnosis.
Keywords: Chemotherapy; Desmoplastic small round cell tumor; Fluorescence in situ hybridization; Reverse transcriptase polymerase chain reaction.