Methods.31325 thyroid patients were operated in the St.-Petersburg Center of Endocrine Surgery and Oncology. Among them 18 (0.06%) cases of MEN were detected, including 8 (0.02%) children. The diagnosis of MEN-2 was confirmed by genetic investigation in all 8 children (3 girls, 5 boys) 4-18 years old. Genetic research confirmed Sippl’s syndrome in 7 children, Gorlin’s syndrome - in 1 10 years old girl.

Results and discussion.The reason for examination of 6 children was MEN identified in adult family members operated on for medullary carcinoma. In 2 cases genetic study was conducted after detection of medullary cancer in pediatric patients. Three patients operated on in childhood belonged to the same family, 5 members of which had syndrome MEH-2a in three generations. Multifocal medullary thyroid cancer with cervical metastases was detected in a girl with MEN-2b. Before surgery, 4 (50%) children did not have manifestations of medullary cancer. Microcarcinoma identified intraoperatively in 1 boy. Increase of the calcitonin and thyroid nodules were diagnosed in 4 cases. All 8 patients underwent thyroidectomy, in 7 cases - central lymphadenectomy. Lateral lymphadenectomy was performed in 2 cases, including 1 Gorlin’s syndrome. Histological examination showed normal thyroid in 2 children, C-cell hyperplasia - in 1, medullary cancer - in 5. Multifocal medullary cancer T4N1bM1 was revealed in the patient with MEN-2b. Parathyroid adenoma was removed in 1 child.

Conclusion.Thyroidectomy was prophylactic in only 3 children. Early thyroidectomy (under 5 years old) prevents the development of medullary cancer.