CHARACTERISTICS OF DIFFERENTIATED THYROID-CARCINOMA IN CHILDREN AND ADOLESCENTS WITH RESPECT TO AGE, GENDER, AND HISTOLOGY

BACKGROUND. Because of its rarity there have been only a few detailed studies on differentiated thyroid carcinoma (DTC) in children. The cur rent investigation was undertaken to assess the characteristics of DTC with respect to age, gender, and histology in children and adolescent s. METHODS. In a questionnaire-based survey, data from 114 children an d adolescents with DTC (age range, 3-18 years) was collected from 65 c linical institutions in Germany. Characteristics of 80 females and 34 males were evaluated and the influence of age, gender, histology, mult icentric growth, tumor stage, and lymph node involvement on distant me tastases was tested using multivariate discriminant analysis. Comparis on between groups was performed using the Student's t test and chi-squ are test. Correlation between incidence and age was assessed by linear regression analysis. RESULTS. The overall incidence of thyroid carcin oma in females was higher than in males, with a peak of female/male ra tio occurring at puberty. The incidence of DTC correlated with age in females < 16 years (correlation coefficient [r] = 0.84; P = 0.0006), w hich was more pronounced in children with papillary thyroid carcinoma (PTC) (r = 0.83; P = 0.006) but not in those with follicular thyroid c arcinoma (FTC) (r = 0.20; P = 0.16). FTC was associated with less adva nced disease (P = 0.009), fewer lymph nodes involved (P = 0.007), and fewer metastases (P = 0.02) compared with PTC. Males tended to have a higher risk for distant metastases. However, statistical analysis fail ed to reach a level of significance (P = 0.08). Multivariate analysis revealed tumor stage as the only powerful factor (P = 0.02) correlated with distant metastasis. CONCLUSIONS. The incidence of PTC shows a ma rked increase in females with the highest female/male ratio occurring at puberty, Childhood thyroid carcinoma frequently is associated with lymph node involvement, distant metastases, and extrathyroidal tumor i nfiltration. In children ETC appears to be less aggressive than PTC. A dvanced local-regional extension stage appears to be the most powerful factor influencing the risk for distant metastases in children. (C) 1 997 American Cnncer Society.