Complete surgical excision is effective treatment for children with immature teratomas with or without malignant elements: A pediatric oncology group/children's cancer group intergroup study

Purpose: To determine whether the 3-year event-free survival (EFS) of child ren with completely resected immature teratomas is greater than 85%. Patients and Methods: Patients with immature teratomas treated at Pediatric Oncology Group or Children's Cancer Group institutions were eligible. path ology was centrally reviewed to confirm diagnosis and tumor grading. Follow -up included physical examination, measurement of tumor markers (alpha feto protein and human chorionic gonadotropin), and imaging. All patients were m onitored for events, defined as tumor recurrence, second malignancy, or dea th. Results: Seventy-three children (median age, 7.8 years) with extracranial i mmature teratomas were enrolled on study. Primary tumor sites included ovar ian (n = 44), testicular (n = 7), and extragonadal(n = 22). However, on rev iew, 23 patients had foci of yolk sac tumor (n = 21) or primitive neuroecto dermal tumor (n = 2), whereas 50 herd pure immature teratomas, twenty-five patients had increased alpha fetoprotein (n = 18), human chorionic gonadotr opin (n = 5), or both (n = 2); nine had foci of yolk sac tumor on review. P athology review identified 23 patients with grade 1, 29 with grade 2, and 2 1 with grade 3 immature teratomas. With a median follow-up of 35 months, th e overall 3-year EFS was 93% (95% confidence interval, 86% to 98%), with 3- year EFS of 97.8%, 100%, and 80% for patients with ovarian, testicular, and extragonadal tumors, respectively. Only four of 23 patients with immature teratoma and malignant foci developed recurrence, suggesting that surgical resection followed by close observation are effective treatment, Overall, f ive patients had disease recurrence 4 to 7 months from diagnosis, and four (80%) are disease free after platinum-based therapy The fifth patient has r esidual tumor after cisplatin, etoposide, and bleomycin treatment requiring further therapy. Conclusion: Surgical excision is safe and effective treatment for 80% to 10 0% of children with immature teratoma. (C) 1999 by American Society of Clin ical Oncology.