title: Intra-abdominal desmoplastic small round cell tumors: CT findings and clinicopathological correlations in 13 cases.
abstract: OBJECTIVE
  We report computed tomography (CT) findings in 13 patients with a primary abdominal desmoplastic small round cell tumor.
  
  
  METHODS
  13 cases (12 men, 1 woman, mean age=24.8 years) were found in our hospital database between 1991 and 2003. Clinical, CT and histopathological features were studied retrospectively.
  
  
  RESULTS
  Peritoneal involvement was the most common feature. In 10 cases, several lobulated peritoneal soft tissue masses (with a mean of four masses per patient) were seen. Two patients had diffused irregular peritoneal carcinomatosis without any distinct peritoneal masses. One patient had a solitary mass in the pelvic space. The main sites of peritoneal involvement were the pelvic space (n=7), omentum (n=5), retroperitoneal space (n=4), small bowel mesentery (n=3), paracolic gutter (n=2 on the right and n=1 on the left), transverse colon mesentery (n=1), peri-splenic space (n=1), peri-hepatic space (n=1). The soft tissue masses were often bulky (mean 6cm, range 1-28cm), lobulated and heterogeneous with hypodense areas (in 73% of cases). In six cases, moderate ascites was seen. In one case of pelvic involvement, unilateral hydronephrosis was seen. Adenopathies were present in seven cases at the time of the diagnosis (at intraperitoneal, retroperitoneal and pelvic sites in six patients and in the groin in one patient). Five patients had liver metastases (four lesions per case excepted one patient with 30 metastases). Associated thoracic metastases were seen in three patients. The diagnosis was confirmed with four CT-guided percutaneous biopsies.
  
  
  CONCLUSIONS
  Although CT features are nonspecific, the diagnosis of desmoplastic small round cell tumor may be suspected in young men with multiple bulky heterogeneous peritoneal soft tissue masses. Imaging is useful for staging and also to guide biopsies.
authors.affiliation: Department of Radiology, Institute Gustave Roussy, 39 Rue Camille Desmoulines, 94805 Villejuif Cedex, France.
authors.forename: Malik
authors.initials: M
authors.lastname: Chouli
authors.forename: Juliette
authors.initials: J
authors.lastname: Viala
authors.forename: Clarisse
authors.initials: C
authors.lastname: Dromain
authors.forename: Karim
authors.initials: K
authors.lastname: Fizazi
authors.forename: Pierre
authors.initials: P
authors.lastname: Duvillard
authors.forename: Daniel
authors.initials: D
authors.lastname: Vanel
mesh_terms: D000008:Abdominal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D000293:Adolescent; D000328:Adult; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D011860:Radiography, Abdominal; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods*