Germ cell tumor

Germ cell tumor

High magnification micrograph of a seminoma, a type of germ cell tumor.

A germ cell tumor (GCT) is a type of neoplasm derived from germ cells. Germ cells are the reproductive cells of the body, and they are responsible for the production of spermatozoa in males and ova in females. Germ cell tumors can occur in the gonads (testes and ovaries) or in extragonadal sites such as the mediastinum, retroperitoneum, and the central nervous system.

Classification

Germ cell tumors are classified into two main types: seminoma and non-seminomatous germ cell tumors (NSGCTs).

Seminoma

Seminomas are a type of germ cell tumor that tend to grow slowly and are sensitive to radiation therapy. They are most commonly found in the testes but can also occur in extragonadal sites.

Non-seminomatous germ cell tumors

NSGCTs include a variety of tumor types such as embryonal carcinoma, yolk sac tumor, choriocarcinoma, and teratoma. These tumors tend to be more aggressive than seminomas and may require a combination of surgery, chemotherapy, and radiation therapy for treatment.

Epidemiology

Relative incidences of different types of testicular tumors.

Germ cell tumors are most commonly diagnosed in young adults, particularly between the ages of 15 and 35. They are more common in males than females, with testicular germ cell tumors being the most prevalent type in men.

Pathophysiology

Germ cell tumors arise from germ cells that fail to undergo normal differentiation and maturation. The exact cause of this abnormal development is not fully understood, but it is believed to involve a combination of genetic and environmental factors.

Clinical presentation

The symptoms of germ cell tumors vary depending on the location and type of the tumor. Testicular germ cell tumors often present as a painless mass in the testicle, while ovarian germ cell tumors may cause abdominal pain or swelling. Extragonadal germ cell tumors can cause symptoms related to the compression of nearby structures.

Diagnosis

Diagnosis of germ cell tumors typically involves a combination of imaging studies, serum tumor markers, and biopsy. Common tumor markers include alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (β-hCG), and lactate dehydrogenase (LDH).

Treatment

The treatment of germ cell tumors depends on the type, stage, and location of the tumor. Seminomas are often treated with radiation therapy, while NSGCTs may require chemotherapy and surgical resection.

Prognosis

The prognosis for germ cell tumors is generally favorable, especially when detected early. Seminomas have a high cure rate with appropriate treatment, and many NSGCTs can also be successfully treated.

Related pages

• Testicular cancer
• Ovarian cancer
• Teratoma
• Embryonal carcinoma