this is a surgically proven small bowel carcinoid tumor. Where is the desmoplastic reaction? Who knows.

From the good AJR article: http://www.ajronline.org/content/182/3/559.full

On CT, a carcinoid tumor appears as an ill-defined mesenteric mass containing calcification in up to 70% of cases [26] (Fig. 4). The mesenteric mass appears to be spiculated with a stellate pattern [27] (Fig. 5). Occasionally, the tumor may appear cystic. The size of the mass can vary from 1 cm or less to several centimeters. Because of the mesenteric fibrosis and desmoplastic reaction, the mesenteric vessels may be involved, either directly as a result of encasement and narrowing or indirectly as a result of the secretion of neuroendocrine chemicals that can affect the vessel wall.