Dysgerminoma and gonadal dysgenesis: the need for a new diagnosis tree for suspected ovarian tumours.
PURPOSE
Diagnosis of dysgerminoma in the paediatric age group is uncommon, and most cases arise from dysgenetic gonads of 46, XY pure gonadal dysgenesis (PGD) patients. Bilateral gonadectomy is mandatory in these patients. So, the preoperative diagnosis of PGD is important in order to avoid multiple surgical procedures and delayed patient information in the case of a suspected 'ovarian' tumour. Our aim was to discuss preoperative clues that can lead to suspicion of dysgerminoma in the context of PGD.


MATERIALS AND METHODS
We reviewed the charts of six patients treated for dysgerminoma associated with 46, XY PGD. We focused on particularities of clinical and biological evaluations.


RESULTS
Median age at diagnosis was 11 years. Pubertal development was absent or incomplete even at late ages. Dysgerminoma was associated with gonadoblastoma foci in all cases. Tumoral marker profile was a normal alfafetoprotein level, a high lactate dehydrogenase level and normal or moderate human chorionic gonadotropin (βHCG) secretion, except for one patient who had a mixed tumour with notably a choriocarcinoma share (high βHCG). Follicle-stimulating hormone (FSH) level was very high in all patients tested and, interestingly, also in one prepubertal patient.


CONCLUSIONS
In the case of a suspected ovarian tumour, delayed pubertal development, moderate βHCG level and elevated FSH level are clinical and biological clues to a diagnosis of dysgerminoma in the context of PGD and should prompt karyotype analysis before surgery. Because FSH is an efficient indirect marker of this condition, we suggest including this analysis in the management of gonadal tumours.