Long-term survival rates were correlated with selected clinical features in 479 patients with
embryonal carcinoma of the testis and 33 patients with
endodermal sinus tumor (infantile
embryonal carcinoma,
yolk sac tumor). In the period 1977 to 1982
embryonal carcinoma accounted for 26.8% of newly diagnosed
germ cell tumors and 43% of nonseminomatous
germ cell tumors entered in the Centralized
Cancer Patient Data System. Among patients with
embryonal carcinoma, over 80% were diagnosed in the 15-to-34 year age group. Seventy-four percent of the patients had metastatic disease at the time of diagnosis, and 50% of these had distant
metastases, attesting to the aggressiveness of
embryonal carcinoma and its tendency to early hematogenous spread. Despite the highly malignant nature of the
tumor, the overall 5-year survival rate with treatments used was an excellent, 88%. Survival was correlated with the extent of disease at the time of diagnosis; the 5-year actuarial survival rates for patients with localized, regional, and distant disease were 98%, 96%, and 74%, respectively.
Endodermal sinus tumor was uncommon (1.8% of all testicular
germ cell tumors), occurred predominantly in the younger age group (0-24 years), and in 50% of the cases was localized to the testis. The survival rate for the 33 patients with this form of
tumor was slightly worse than for the "adult form" of
embryonal carcinoma. The authors conclude that survival of patients with
embryonal carcinoma has greatly improved over the last decade as a result of improved methods for early detection of metastatic deposits and the effectiveness of newer
chemotherapies in the treatment of disseminated disease.