|Micrograph of a dysgerminoma, H&E stain.|
A tumor of the identical histology but not occurring in the ovary may be described by an alternate name: seminoma in the testis or germinoma in the central nervous system or other parts of the body.
Dysgerminoma accounts for less than 1% of ovarian tumors overall. Dysgerminoma usually occurs in adolescence and early adult life; about 5% occur in pre-pubertal children. Dysgerminoma is extremely rare after age 50. Dysgerminoma occurs in both ovaries in 10% of patients and, in a further 10%, there is microscopic tumor in the other ovary.
Abnormal gonads (due to gonadal dysgenesis and androgen insensitivity syndrome) have a high risk of developing a dysgerminoma. Most dysgerminomas are associated with elevated serum lactic dehydrogenase (LDH), which is sometimes used as a tumor marker.
Signs and symptoms
They are exceptionally associated with hypercalcemia. On gross examination, dysgerminomas present with a smooth, bosselated (knobby) external surface, and is soft, fleshy and either cream-coloured, gray, pink or tan when cut. Microscopic examination typically reveals uniform cells that resemble primordial germ cells. Typically, the stroma contains lymphocytes and about 20% of patients have sarcoid-like granulomas. Metastases are most often present in the lymph nodes.
hCG tumour markers are elevated in approximately 75% of cases.
Dysgerminoma characterized by uniform cells separated by fibrous septa with lymphocytes, H&E stain.
Low-power view of a dysgerminoma infiltrating the colonic wall, H&E stain.
Dysgerminomas, like other seminomatous germ cell tumors, are very sensitive to both chemotherapy and radiotherapy. For this reason, with treatment patients' chances of long-term survival, even cure, is excellent.
- Behtash N, Karimi Zarchi M (2007). "Dysgerminoma in three patients with Swyer syndrome". World J Surg Oncol. 5 (1): 71. doi:10.1186/1477-7819-5-71. PMC 1934908. PMID 17587461.
- "dysgerminoma" at Dorland's Medical Dictionary
- Nelson Textbook of Pediatrics, 18th ed. Chapter 553. Question 11, Gynecologic Problems of Childhood