Good Prognosis
        Nonseminoma
        Seminoma
Intermediate Prognosis
        Nonseminoma
        Seminoma
Poor Prognosis
        Nonseminoma
        Seminoma

Extragonadal germ cell tumors can be benign (teratoma) or malignant. The latter group can be divided into seminoma and nonseminoma germ cell tumors, which include embryonal carcinomas, malignant teratomas, endodermal sinus tumors, choriocarcinomas, and mixed germ cell tumors.

Extragonadal germ cell tumors occur much more commonly in males than in females [1] and are usually seen in young adults. They are aggressive neoplasms and can arise virtually anywhere, but typically the site of origin is in the midline (mediastinum, retroperitoneum, or pineal gland). Gonadal origin should be excluded by careful testicular examination and ultrasound. The diagnosis can be difficult and should be considered in any patient with a poorly defined epithelial malignancy, particularly young individuals with midline masses.[2,3]

An international germ cell tumor prognostic classification has been developed based on a retrospective analysis of 5,202 patients with metastatic nonseminomatous germ cell tumors and 660 patients with metastatic seminomatous germ cell tumors.[4] All patients received treatment with cisplatin-containing or carboplatin-containing therapy as their first chemotherapy course. The prognostic classification, shown below, was agreed on in early 1997 by all major clinical trial groups worldwide and should be used for the reporting of clinical trials' results of patients with extragonadal germ cell tumors.

• Testis/retroperitoneal primary

  and

• No nonpulmonary visceral metastases

  and

• Good markers - all of:
  • AFP less than 1,000 ng/mL

    and

  • hCG less than 5,000 iu/L (1,000 ng/mL)

    and

  • LDH less than 1.5 x upper limit of normal

56% of nonseminomas

5-year progression-free survival (PFS) rate of 89%

5-year survival rate of 92%

• Any primary site

  and

• No nonpulmonary visceral metastases

  and

• Normal AFP, any hCG, any LDH

90% of seminomas

5-year PFS rate of 82%

5-year survival rate of 86%

• Testis/retroperitoneal primary

  and

• No nonpulmonary visceral metastases

  and

• Intermediate markers - any of:
  • AFP 1,000 ng/mL or greater and 10,000 ng/mL or less

    or

  • hCG 5,000 iu/L or greater and 50,000 iu/L or less

    or

  • LDH 1.5 × N or greater and 10 × N or less

28% of nonseminomas

5-year PFS rate of 75%

5-year survival rate of 80%

• Any primary site

  and

• Nonpulmonary visceral metastases

  and

• Normal AFP, any hCG, any LDH

10% of seminomas

5-year PFS rate of 67%

5-year survival rate of 72%

• Mediastinal primary

  or

• Nonpulmonary visceral metastases

  or

• Poor markers - any of:
  • AFP greater than 10,000 ng/mL

    or

  • hCG greater than 50,000 iu/L (1,000 ng/mL)

    or

  • LDH greater than 10 × upper limit of normal

16% of nonseminomas

5-year PFS rate of 41%

5-year survival rate of 48%

No patients are classified as poor prognosis.

References

1. Mayordomo JI, Paz-Ares L, Rivera F, et al.: Ovarian and extragonadal malignant germ-cell tumors in females: a single-institution experience with 43 patients. Ann Oncol 5 (3): 225-31, 1994.  [PUBMED Abstract]
   
   
2. Greco FA, Vaughn WK, Hainsworth JD: Advanced poorly differentiated carcinoma of unknown primary site: recognition of a treatable syndrome. Ann Intern Med 104 (4): 547-53, 1986.  [PUBMED Abstract]
   
   
3. Hainsworth JD, Greco FA: Extragonadal germ cell tumors and unrecognized germ cell tumors. Semin Oncol 19 (2): 119-27, 1992.  [PUBMED Abstract]
   
   
4. International Germ Cell Consensus Classification: a prognostic factor-based staging system for metastatic germ cell cancers. International Germ Cell Cancer Collaborative Group. J Clin Oncol 15 (2): 594-603, 1997.  [PUBMED Abstract]