Genetic Causes of Rare Pediatric Ovarian Tumors.

BACKGROUND: Ovarian tumors in childhood and adolescence are distinguished from those that arise in adulthood by their histological subtype. These tumors may arise as the first manifestation of a cancer predisposition syndrome. Correct diagnosis of the syndrome may offer the possibility of surveillance for other members of the patients family. PURPOSE: To summarize current knowledge about paediatric ovarian tumors that may be associated with genetically defined cancer syndromes. Juvenile granulosa cell tumors occur in those with Ollier disease and Maffucci syndrome; they are caused by postzygotic IDH1 and IDH2 gene mutations. Sertoli-Leydig cell tumors usually arise in association with DICER1 syndrome, which is caused by germline DICER1 gene mutations. Sex cord tumors with annular tubules and Sertoli cell tumors may arise in patients with Peutz-Jeghers syndrome; this syndrome is caused by germline STK11 gene mutations. The majority of germ cell tumors develop in the context of gonadal dysgenesis. In XY gonadal dysgenesis, the presence of a Y chromosome material renders the patient at increased risk for developing gonadal malignancy. Characteristically, these patients develop gonadoblastoma, which has the potential to evolve into dysgerminoma and exhibit malignant behavior. Sex-chromosome aneuploidy syndromes or mutations in genes involved in gonadal development and differentiation may cause gonadal dysgenesis. Small cell carcinoma of the ovary of a hypercalcaemic type is usually caused by loss-of-function mutations in the SMARCA4 gene. CONCLUSION: Ovarian tumors are uncommon during childhood and adolescence. It is always necessary to consider gonadal dysgenesis or any of the inherited cancer syndromes. These patients require interdisciplinary care, careful noting of personal and family history, precise clinical examination, laboratory testing, and differential diagnosis by a clinician with a good knowledge of genetic syndromes. Expert pathological review may be required for correct diagnoses. This is necessary for appropriate management and to establish an association with hereditary cancer syndromes. The work was supported by the Ministry of Health of the Czech Republic - Conceptual Development of Research Organization, Faculty Hospital of Ostrava /2015. We thank to Lenka Foretová, M.D., Ph.D., (MMCI, Brno) and Radoslava Tomanová, M.D., (Institute of Pathology, University Hospital Ostrava) for rewarding advice, Mrs. Jana Němcová (Department of Medical Genetics, University Hospital Ostrava), Bc. Ludmila Stuchlá and Mrs. Lenka Zivčáková (Medical Library, University Hospital Ostrava) for help during manuscript preparation. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 10. 3. 2019 Accepted: 16. 4. 2019.