We analyzed 72 patients with ovarian
sex cord-stromal tumors (OSCST) registered at the German Pediatric
Tumor Registry in Kiel over a 20-year period. Juvenile
granulosa cell tumors (JGCT, n=48) were the most frequent histological subtype. In addition, there were 14
Sertoli-Leydig cell tumors, 5 sclerosing stromal
tumors, 2 sex cord
tumors with annular tubules, 2
thecomas and 1
steroid cell
tumor. Stage according to FIGO (International Federation of Gynecologists and Obstetricians) was Ia in 39 patients, Ic in 17 patients, II in 3 patients and III in 1 patient (60 patients with complete data). Compared with adult
granulosa cell tumors, JGCT showed pronounced mitotic activity [mean 9.8 mitoses/10 high power field (HPF)], which was significantly higher than in other histological subtypes (2.7/10 HPF, P=0.001). Immunohistochemical analysis revealed frequent coexpression of
vimentin (positive in 52/52 examined
tumors),
cytokeratin (27/33), and
inhibin (19/20). Of patients, 12 with Ic or higher stage
tumors received adjuvant cisplatinum-based
chemotherapy. Event-free survival
at 10 years was 0.88 +/- 0.05 (38/43 patients with follow-up data). Outcome significantly correlated with stage and mitotic activity (<20 versus > or =20 mitoses/10 HPF: event-free survival 1.0 versus 0.48 +/- 0.05, P=0.0001). In conclusion, this analysis confirms that the majority of patients with OSCST present at low
tumor stage and that prognosis in these patients is excellent. Refractory
tumors are characterized by high proliferative activity. Therefore, histopathological evaluation substantially contributes to risk assessment in patients with OSCST and might be useful for
therapy stratification in prospective therapeutic protocols.