Table 1.

Genetic alterations and exposure-related characteristics among cases of thyroid cancer developed after the Chernobyl accident in Ukraine

Genetic Alteration	Mutation frequency	I-131 dose, mean (Gy)	Age at exposure, mean (yr)	Age at surgery, mean (yr)	Time since exposure, mean (yr)
RET/PTC1	14 (22%)	1.04	6.4	23.6	16.9
RET/PTC3	8 (13%)	1.54	6.3	20.1	13.7
BRAF	9 (15%)	0.27	10.2	27.1	16.8
RAS *	5 (8%)	0.20	10.9	29.4	18.6
PAX8/PPARγ *	2 (3%)	0.62	12.2	25.8	13.5
No known mutation	25 (40%)	1.97	7.8	24.4	16.6
Total/overall	62 (100%)	1.27	8.1	24.6	16.5

^*One case was found to be positive for both NRAS mutation and PAX8/PPARγ rearrangement.