Childhood extracranial germ cell tumors (GCTs) are very heterogenous. The benefits and limitations of therapy are related to differences in histology. For example, pediatric GCTs, such as mature and immature teratomas, may not respond to chemotherapy.
Prognosis and appropriate treatment for extracranial GCTs depend on many factors, including the following:[1,2,3,4]
- Histology (e.g., seminomatous vs. nonseminomatous).
- Age (young children vs. adolescents).
- Stage of disease.
- Primary site of disease.
To maximize the likelihood of long-term survival while minimizing the likelihood of treatment-related long-term sequelae (e.g., secondary leukemias, infertility, hearing loss, and renal dysfunction), children with extracranial malignant GCTs need to be cared for at pediatric cancer centers with experience treating these rare tumors.
On the basis of clinical factors, appropriate treatment for extracranial GCTs may involve one of the following:
- Surgical resection followed by careful monitoring for disease recurrence.
- Initial surgical resection followed by platinum-based chemotherapy.
- Diagnostic tumor biopsy and preoperative platinum-based chemotherapy followed by definitive tumor resection.
For patients with completely resected immature teratomas at any location (even those with malignant elements) and patients with localized, completely resected (stage I) gonadal tumors, additional therapy may not be necessary; however, close monitoring is important.[6,7] The watch-and-wait approach requires scheduled serial physical examination, tumor marker determination, and primary tumor imaging to ensure that a recurrent tumor is detected without delay.
Surgery is an essential component of treatment. Specific treatments will be discussed for each tumor type.
Germinomas (testicular and mediastinal seminomas in males and ovarian dysgerminomas in females) are sensitive to radiation, but radiation therapy is rarely recommended. With the advent of effective chemotherapy, it became possible for patients to avoid the toxic effects of radiation.
Before effective chemotherapy became available, children with extracranial malignant GCTs had 3-year survival rates of 15% to 20% with surgery and radiation therapy,[8,9,10] although young boys with localized testicular tumors did well with surgical resection.[11,12] Cisplatin-based chemotherapy has significantly improved the outcome for most children and adolescents with extracranial GCTs; 5-year survival rates are now more than 90%.