Two young adults that presented with intra-abdominal desmoplastic small cell tumors (DSCT) without any evidence of a primary site are described. Both cases share the clinical characteristic features of this rare tumor which include predominant intra-abdominal location as initial presentation, nesting pattern of growth, intense desmoplastic reaction, immunohistochemical reactivity for epithelial, neural and muscle markers, and highly aggressive behavior. Aggressive chemotherapy with a cisplatin-containing regimen was the main therapy to our patients. Up to the present, both cases are alive with disease. The survival is 18 and 15 months from the initial diagnosis, respectively. Interestingly, one of the cases encountered an episode of cerebral infarction at the territory of the left middle cerebral artery 12 days after the first cycle of chemotherapy. This is a previously unrecognized manifestation for this tumor type. This causal relationship between chemotherapy and an acute vascular event is the most likely explanation for our patient's stroke.