Clinicostatistical study of ovarian tumors of germ cell origin.

Ovarian tumors of germ cell origin consisted of 440 dermoid cysts, 5 struma ovariis, 3 immature teratomas (G1, G2), 2 carcinoids, 8 dysgerminoma, 3 yolk sac tumors, one choriocarcinoma, 4 dermoid cysts with malignant transformation, and one immature teratoma (G3) of a total of 1,387 ovarian tumors. The patients' mean ages ranged between 17.3 years to 31.9 years, but the mean ages of those with carcinoid and dermoid cyst with malignant transformation were 46.0 and 53.0 years, respectively. In dermoid cyst bilaterality was 17.3% and occurrence during pregnancy or puerperium was 19.6%. In benign tumors, torsion of pedicle and association with pregnancy or puerperium were frequent unlike common epithelial carcinoma, but ascites was rare. Abdominal tumor, pain and metromenorrphagia were the main symptoms, but abdominal distension was scarce with dermoid cysts. The rate of malignant transformation of dermoid cysts was 0.9% overall but 4.3% in patients over 40 years. The prognosis for borderline germ cell tumors was good.