title: Gonadoblastoma and Turner syndrome.
abstract: OBJECTIVE
  The presence of a Y chromosome in the extrascrotal gonad of patients with intersex disorders has been associated with a high risk of GB and, potentially, GCT. Recently, modern sophisticated genotyping has revealed a subgroup of TS cases with a mosaic karyotype expressing a Y chromosome. We sought to evaluate this group of patients and address their risk of gonadoblastoma.
  
  
  METHODS
  We reviewed the records and genotyping of all females newly diagnosed with TS between 1990 and 2002 at Children's Hospital in Denver. All patients with TS and Y chromosome mosaicism underwent gonadectomy, and the specimens were evaluated for the presence of gonadoblastoma on histological analysis and to identify Y chromosome on genotyping.
  
  
  RESULTS
  A total of 192 girls with a clinical diagnosis of TS were identified between January 1990 and December 2002. Seven records were unavailable and 19 patients did not have karyotypic analyses available in the hospital charts. Of the remaining 166 patients 67 exhibited mosaic cell lines, of whom 8 had 45,X0/46,XY mosaic pattern and 59 had mosaic patterns without Y chromosomal elements. All 8 patients with Y mosaicism underwent uneventful laparoscopic gonadectomy on an outpatient basis. One patient observed to have bilateral dysgenetic gonads after gonadectomy was excluded from the study. Gonadoblastoma (bilateral 2 patients, unilateral 1) was detected in 3 of 7 patients (43%) with Y mosaicism.
  
  
  CONCLUSIONS
  In our series 4.8% of evaluable patients with TS carried a 45,X0/46,XY karyotype. Gonadoblastoma can be evident even at an early age in streak gonads with Y mosaicism and may be bilateral. We recommend prophylactic laparoscopic gonadectomy of streak gonads in patients with TS who carry a Y mosaic genotype, because fertility is not an issue, surgical morbidity is minor and there may be a high potential for malignant transformation of gonadoblastomas in this population.
authors.affiliation: Department of Urology, University of California, San Francisco, San Francisco, California 94143-0738, USA. wbrant@urol.ucsf.edu
authors.forename: William O
authors.initials: WO
authors.lastname: Brant
authors.forename: Ashok
authors.initials: A
authors.lastname: Rajimwale
authors.forename: Mark A
authors.initials: MA
authors.lastname: Lovell
authors.forename: Sharon H
authors.initials: SH
authors.lastname: Travers
authors.forename: Peter D
authors.initials: PD
authors.lastname: Furness
authors.forename: Mathew
authors.initials: M
authors.lastname: Sorensen
authors.forename: Siam
authors.initials: S
authors.lastname: Oottamasathien
authors.forename: Martin A
authors.initials: MA
authors.lastname: Koyle
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D018238:Gonadoblastoma / Q000150:complications*; D006801:Humans; D010051:Ovarian Neoplasms / Q000150:complications*; D014424:Turner Syndrome / Q000150:complications*