title: Magnetic resonance imaging findings of small round cell tumors of the ovary: a report of 5 cases with literature review.
abstract: OBJECTIVE
  To study the magnetic resonance imaging characteristics of the ovarian involvement of small round cell tumors.
  
  
  METHODS
  Magnetic resonance imaging findings were retrospectively reviewed in 5 patients seen at this institution and in 7 patients reported in the literature with ovarian small round cell tumors. Laterality, signal intensity, existence of hemorrhage, calcification, necrosis, septa, cerebroid appearance, and peripheral cysts were evaluated.
  
  
  RESULTS
  Seven patients had bilateral disease, and the others had unilateral disease. The signal intensity was low on T1-weighted imaging (T1WI) in all cases. Signal on T2-weighted imaging (T2WI) and the degree of contrast enhancement varied. No case showed hemorrhage or calcification. Only 1 case demonstrated necrosis. Septa were observed in 3 cases, and a cerebroid appearance was observed in 5 cases. Six patients of reproductive age had multiple small cysts at the periphery of the masses.
  
  
  CONCLUSIONS
  Despite the limited number of cases, peripheral small cysts in the large lobulated solid mass seemed to be a characteristic of the ovarian small round cell tumors in patients of reproductive age.
authors.affiliation: Department of Radiology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan. ytanaka@md.tsukuba.ac.jp
authors.forename: Yumiko Oishi
authors.initials: YO
authors.lastname: Tanaka
authors.forename: Kazumi
authors.initials: K
authors.lastname: Yamada
authors.forename: Akinori
authors.initials: A
authors.lastname: Oki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yoshikawa
authors.forename: Manabu
authors.initials: M
authors.lastname: Minami
mesh_terms: D000293:Adolescent; D000328:Adult; D018288:Carcinoma, Small Cell / Q000175:diagnosis*; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000175:diagnosis*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA