Bilateral primary germ cell testicular tumors. Report of four cases and review of the literature

Bilateral primary germ cell tumors of the testicle are rare. The last comprehensive review of the literature (1955) revealed a 1.6% incidence. However, during the past twenty years, cases have been reported more often, raising the questions of increased frequency due to prolonged survival following surgery and/or roentgen therapy for unilateral tumors. A search of the medical journals during the past two decades fails to show any increased frequency of bilaterality (1.56%). All general combinations of cell types may occur and the tumors may appear simultaneously or sequentially. Successive seminomas are seen more often followed in frequency by concurrent seminomas. Although 50% of the second primaries were diagnosed within five years, 3% of the patients developed the second tumor after 20 years, stressing the need for extended follow-up. Factors affecting the diagnosis, management and prognosis of bilateral testicular tumors are discussed. Four additional cases of bilateral germ cell tumors are described.