Germ Cell Tumors PDF

## II. GERM CELL TUMORS A. 2nd most common type of ovarian tumor (15% of cases) B. Usually occur in women of reproductive age C. Tumor subtypes mimic tissues normally produced by germ cells. 1. Fetal tissue-cystic teratoma and embryonal carcinoma 2. Oocytes-dysgerminoma 3. Yolk sac-endodermal sinus...

## II. GERM CELL TUMORS A. 2nd most common type of ovarian tumor (15% of cases) B. Usually occur in women of reproductive age C. Tumor subtypes mimic tissues normally produced by germ cells. 1. Fetal tissue-cystic teratoma and embryonal carcinoma 2. Oocytes-dysgerminoma 3. Yolk sac-endodermal sinus tumor 4. Placental tissue-choriocarcinoma D. Cystic teratoma 1. Cystic tumor composed of fetal tissue derived from two or three embryologic layers (e.g., skin, hair, bone, cartilage, gut, and thyroid, Fig. 13.13) - Most common germ cell tumor in females; bilateral in 10% of cases 2. Benign, but presence of immature tissue (usually neural) or somatic malignancy (usually squamous cell carcinoma of skin) indicates malignant potential. 3. Struma ovarii is a teratoma composed primarily of thyroid tissue. E. Dysgerminoma 1. Tumor composed of large cells with clear cytoplasm and central nuclei (resemble oocytes, Fig. 13.14); most common malignant germ cell tumor 2. Testicular counterpart is called seminoma, which is a relatively common germ cell tumor in males. 3. Good prognosis; responds to radiotherapy 4. Serum LDH may be elevated. F. Endodermal sinus tumor 1. Malignant tumor that mimics the yolk sac; most common germ cell tumor in children 2. Serum AFP is often elevated. 3. Schiller-Duval bodies (glomerulus-like structures) are classically seen on histology (Fig. 13.15). G. Choriocarcinoma 1. Malignant tumor composed of cytotrophoblasts and syncytiotrophoblasts; mimics placental tissue, but villi are absent 2. Small, hemorrhagic tumor with early hematogenous spread 3. High β-hCG is characteristic (produced by syncytiotrophoblasts); may lead to thecal cysts in the ovary 4. Poor response to chemotherapy H. Embryonal carcinoma 1. Malignant tumor composed of large primitive cells 2. Aggressive with early metastasis