Seminoma

B.Sc (N) Pathology

1. SEMINOMA

2. It is the commonest malignant tumor of the testis. Incident age is between 25- 55 years. It is rare before puberty. Undescended testis is important causative factor

3. TYPES Classic seminoma Spermatocytic seminoma

4. CLASSIC SEMINOMA It constitutes about 90% Gross appearance: Testis is enlarged, bulky, solid, grey white. Smaller nodules appear separated from testicular tissue. Microscopic appearance Tumor tissue consists of cellular tissue and fibrous tissue

5. Tumor cell: The classis seminoma cell is large, round, polygonal, with clear cytoplasm and cell border. These cells have glycogen and stain positive with PAS stain. Nucleus is central, large, dark, hyperchromatic . 1-2 prominent nucleoli

6. Stroma : It is delicate and separates lobules of cellular tissue. It contains lymphocytic infiltration. 20% of tumors show granulomatious reaction

7. Anaplastic seminoma : It constitutes 5% of all seminomas . Features like increased mitotic activity, nuclear irregularity, frequent tumor giant cell do not change the course of disease. Clinical course: Classic seminoma and anaplastic seminoma have better prognosis than other germ cell tumor.

8. SPERMATOCYTIC SEMINOMA It comprises of 5% of all seminomas Occurs inpatients in 6 th decade of life It is bilateral in about 10% of patients. It is slow growing with excellent prognosis

9. Gross appearance: Size is variable, usually larger than classic seminoma . It is soft, yellow, gelatinous. Cut section: Sometimes shows mucoid cyst. Hemorrhage and necrosis is rarely seen Microscopic appearance: It consists of cellular elements, stromal tissue.

10. Tumor cells : It is of four types Medium sized cells: 15-18 μ m, round, abundant eosinophilic cytoplasm. These are predominant. Smaller cells :6-8 μ m, thin rim of eosinophilic cytoplasm.

11. Intermediate cells: size is intermediate. They are very few in number. Giant cells: it is scattered. It has either single large nucleus or multiple nuclei Clinical course: It has got excellent prognosis and do not contain lymphocytes