This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gynaecological Disorders in Obs., Subject name: Gynaecology & Obstetrics
The most common pure germ cell cancer of the ovary is: 
Select and explain. 
A. Choriocarcinoma, B. Dysgerminoma, C. Embryonal cell tumor, D. Malignant teratoma
B: Dysgerminoma
Answer: B: Dysgerminoma 
Explanation: Ans. B. DysgerminomaDysgerminoma:a. It is the most common pure germ cell tumor of ovary.b. It corresponds to Seminoma.c. It is common under the age of 20.d. It is usually unilateral.e. It is neutral.f. It secrets placental alkaline phosphatase.g. It may be associated is hypoplasia or aplasia of part of genital tract.h. It is very radiosensitive.i. It is potentially malignant with malignancy rate of 30-50%.j. Endodermal sinus/yolk sac tumor is 2nd most common germ cell tumor.k. Embryonal cell tumor is rare.