Prepubertal testicular germ cell tumors: 25-year experience in Taipei Veterans General Hospital.

BACKGROUND Due to the rarity of testicular tumors in the prepubertal population, adequate information about their biological course is difficult to document well in a single institution. The purpose of this study was to focus on prepubertal males in an attempt to evaluate clinical features and optimal management among various testicular germ cell tumors with long-term follow-up. METHODS We retrospectively reviewed the records of children younger than 12 years of age with primary testicular germ cell tumors between February 1981 and December 2005 at Taipei Veterans General Hospital. Thirty-four children were diagnosed with adequate clinical and pathologic data. The stage of the disease was determined according to the staging system used by the Children's Oncology Group. Mean follow-up time was 139 months (range, 2-283 months). RESULTS All of the 34 prepubertal patients were diagnosed initially with a painless scrotal mass. The mean age of the patients at diagnosis ranged from 6 months to 84 months (mean, 20.5 months). All patients underwent radical orchiectomy as an initial treatment. Twenty-nine (85.3%) patients had yolk sac tumors, and 5 (14.7%) had mature teratomas. Of the 29 patients with yolk sac tumor, 26 (89.7%) were diagnosed as stage I, 1 (3.4%) as stage III, and 2 (7.0%) as stage IV. Five (19.2%) of the 26 stage I yolk sac tumors progressed to metastasis after radical orchiectomy, and all of these 5 patients later received chemotherapy. One patient initially with stage III yolk sac tumor and 2 patients with stage IV yolk sac tumor were also treated with chemotherapy. Eventually, 1 patient with stage IV yolk sac tumor died due to tumor progression; the remaining 28 patients with yolk sac tumor all survived without tumor relapse after appropriate treatment. In the 5 patients with teratomas, there was no tumor relapse after radical orchiectomy with a mean follow-up time of 139.1 months. The 5-year survival rates for yolk sac tumor and teratomas were 96.5% and 100%, respectively. CONCLUSION The most common prepubertal malignant testicular tumor is yolk sac tumor, and the most common benign testicular tumor is teratoma. Children with testicular germ cell tumors have excellent long-term survival rates after appropriate treatment.