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Gonadoblastoma and Turner syndrome
William O Brant1, Ashok Rajimwale, Mark A Lovell
1Department of Urology, University of California, San Francisco, San Francisco, California 94143-0738, USA. wbrant@urol.ucsf.edu
The Journal of Urology
|April 8, 2006
Summary
Patients with Turner syndrome (TS) and Y chromosome mosaicism have a high risk of gonadoblastoma. Prophylactic gonadectomy is recommended due to the potential for malignant transformation in these streak gonads.
Area of Science:
- Genetics
- Gynecology
- Pediatrics
Background:
- Y chromosome presence in extrascrotal gonads is linked to gonadoblastoma (GB) and germ cell tumors (GCT).
- Mosaic karyotypes with Y chromosome expression are found in a subgroup of Turner syndrome (TS) cases.
Purpose of the Study:
- To evaluate the risk of gonadoblastoma in TS patients with Y chromosome mosaicism.
- To assess the clinical significance of Y chromosome mosaicism in TS.
Main Methods:
- Reviewed records and genotyping of females diagnosed with TS (1990-2002).
- Analyzed gonadectomy specimens for gonadoblastoma and Y chromosome presence in patients with Y mosaicism.
Main Results:
- Eight patients with TS exhibited a 45,X0/46,XY mosaic pattern.
- Gonadoblastoma was detected in 3 of 7 evaluable patients (43%) with Y mosaicism.
- Malignant transformation was observed even in early-stage streak gonads.
Conclusions:
- 4.8% of evaluable TS patients carried a 45,X0/46,XY karyotype.
- Prophylactic laparoscopic gonadectomy is recommended for streak gonads in TS patients with Y mosaic genotype.
- Early detection and removal are crucial due to high malignant transformation potential.
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