Ovarian Tumors — Germ Cell

Which tumor marker is most specific and sensitive for monitoring dysgerminoma and yolk sac tumor of the ovary?

Immature teratoma of the ovary is graded based on the amount of immature neural tissue present. What is the defining feature of Grade 3 immature teratoma?

A 22-year-old unmarried woman from Delhi presents with a 3-month history of progressive abdominal distension and mild left lower abdominal pain. On examination, she appears anxious and has a palpable left adnexal mass. Serum β-hCG is 45,000 mIU/mL (normal <5), AFP is 8,500 ng/mL (normal <10), and LDH is elevated at 680 U/L. Pelvic ultrasound shows a 12 cm heterogeneous left ovarian mass with cystic and solid components. What is the most likely diagnosis?

A 16-year-old girl from Mumbai presents to the emergency department with acute severe left lower abdominal pain and nausea for 6 hours. On examination, she is in distress with a rigid, tender left lower abdomen and guarding. Pelvic ultrasound reveals a 15 cm left ovarian mass with internal hemorrhage and free fluid in the pelvis. Serum AFP is 2,200 ng/mL (normal <10), β-hCG is 12 mIU/mL (normal <5), and hemoglobin is 9.2 g/dL. Emergency left oophorectomy is performed. Histopathology shows sheets of cuboidal cells with hyaline globules, microcystic pattern, and areas of hemorrhage and necrosis. What is the most likely diagnosis?

A 22-year-old woman undergoes surgery for a right ovarian mass. Pathology shows a solid tumor with sheets of large, clear cells with central nuclei, resembling seminoma. No Schiller-Duval bodies or glandular differentiation is seen. Serum AFP and β-hCG are both negative. Which feature best distinguishes this dysgerminoma from yolk sac tumor?