The ret/PTC mutations are common in sporadic papillary thyroid carcinoma of children and young adults

The ret/PTC rearrangements (PTC-1, PTC-3, and PTC-3) are characteristic of papillary thyroid cancer (PTC). In adults, PTC-1 is common and may be assoc iated with an aggressive clinical course. The incidence and significance of ret/PTC mutations are less well understood in children. We examined sponta neous PTC from 33 patients (23 females and 10 males) with a median age of 1 8 yr (range, 6-21 yr) and a median follow-up of 3.5 yr (range, 0-13.4 yr). The ret/PTC mutations were identified in 15 tumors (45%), including 8 PTC-1 (8 of 15, 53%), 2 PTC-P (2 of 15, 13%), 2 PTC-3 (2 of 15, 13%), and 3 13 d f 15, 20%) combined PTC mutations (PTC-1 and PTC-P). This distribution is s ignificantly different (P = 0.001, by chi(2) analysis) from that reported f or children with radiation-induced PTC. There was no correlation between th e presence or type of ret/PTC mutation and patient age, tumor size, focalit y, extent of disease at diagnosis, or recurrence. We conclude that ret/PTC mutations are 1) common in sporadic childhood PTC, 2) predominantly PTC-1, 3) frequently multiple, and 4) of different distribution than that reported for children with radiation-induced PTC.