Differentiated thyroid carcinoma in children and adolescents: a 37-year experience in 85 patients.

UNLABELLED: This study reports on 85 differentiated thyroid carcinoma (DTC) (72 papillary, 13 follicular) patients, younger than 18 yr of age at the time of diagnosis, consecutively treated during the period 1958-1995.

METHODS: Follow-up (median: 111 mo, range 1-324 mo) consisted of clinical examination, serum thyroglobulin (Tg), 131I whole-body scintigraphy (whole-body scan) and other imaging procedures.

RESULTS: Forty-six patients had undergone total thyroidectomy, 38 partial thyroidectomy and 1 thyroid biopsy. In 47 patients, lymph-adenectomy was also performed. Five patients were treated after surgery by external radiotherapy, 59 by 131I therapy and 16 by both modalities. Iodine-131 therapy was successful in ablating thyroid remnants in 35/48 cases, lymph node metastases in 8/11 cases and lung metastases in 12/16 cases. Among the patients with scintigraphic-confirmed disappearance of lung metastases, serum Tg was still detectable in 10 cases, but continued to decrease spontaneously even without further therapeutic doses of 131I. All patients were still alive after a median period of 137 mo (range 5-444 mo). Six patients experienced a recurrence of the disease in the neck. Sixty-seven patients were free of disease, 3 had lymph node metastases, 4 lung metastases and 11 had detectable levels of Tg without demonstrable metastases. No impairment of female fertility or untoward genetic effects were noticed. One male patient, treated with 3.33 GBq of 131I, was infertile due to oligospermia. One case of gastric cancer and one of breast cancer occurred 8 and 19 yr, respectively, after 131I therapy.

CONCLUSION: Iodine-131 therapy is highly effective in reducing lung metastases, but undetectable levels of Tg are seldom achieved. Total thyroidectomy and 131I therapy is an effective and safe treatment for the majority of patients with DTC diagnosed in childhood or adolescence.