Papillary thyroid carcinoma of childhood and adolescence: a 30-year experience at the Istituto Nazionale Tumori in Milan.

BACKGROUND: Survival rates are reportedly excellent for papillary thyroid carcinomas (PTCs) in childhood/adolescence, despite their strong tendency to spread. The aim of this study was to verify this assumption in a single-institution series spanning a 30-year period with a very long follow-up. PROCEDURE: From 1968 to 2001, 74 cases of thyroid carcinoma were collected. The papillary histological type was confirmed in 42 cases with available slides; we recorded the sex, age at diagnosis, age of menarche, tumor side and size, TNM/pTNM classification, multicentricity, vascular invasion, type of surgery, post-operative complications, post-surgical therapies and outcome up to May 31, 2004. RESULTS: The female/male ratio was 2.2; pT4, pN1 and M1 cases were 52%, 95%, and 12% (four in lungs and one in bone), respectively. Total thyroidectomy was performed in 33 patients, hemithyroidectomy in 8, and a biopsy in 1 inoperable case. Nine patients (21%) relapsed, six in the cervical lymph nodes and three in the lungs. After a median follow-up of 189 months, all patients were alive, two of them with evidence of disease. Overall and progression-free survival curves were independent of sex, age, TNM/pTNM classification, or type of surgery. Overall survival was also independent of recurrence. CONCLUSIONS: Unlike its adult counterpart, PTC of childhood and adolescence is a cancer with a high frequency of spread, but an excellent outcome irrespective of sex, age at diagnosis, TNM/pTNM classification, type of surgery, recurrence. Since pediatric PTCs proved highly responsive to hormone manipulation, it is worth considering a different therapeutic approach from adult cases.