Ab. Schneider et al., THYROID-NODULES IN THE FOLLOW-UP OF IRRADIATED INDIVIDUALS - COMPARISON OF THYROID ULTRASOUND WITH SCANNING AND PALPATION, The Journal of clinical endocrinology and metabolism, 82(12), 1997, pp. 4020-4027
In 1974 we began a prospective study of a cohort of 4296 individuals e
xposed to therapeutic head and neck irradiation during childhood for b
enign conditions. To define the role of thyroid ultrasonography in fol
lowing irradiated individuals, we studied a subgroup of 54 individuals
. They all had been screened between 1974-1976 and had normal thyroid
scans and no palpable nodules at that time. Thyroid ultrasonography, t
hyroid scanning, physical examination, and serum thyroglobulin measure
ments were performed. One or more discrete ultrasound-detected nodules
were present in 47 of 54 (87%) subjects. There were a total of 157 no
dules, 40 of which were 1.0 cm or larger in largest dimension. These 4
0 nodules occurred in 28 (52%) of the subjects. Thirty (75%) of these
1.0-cm or larger nodules matched discrete areas of diminished uptake o
n corresponding thyroid scans. The 10 that did not match (false negati
ve scans for greater than or equal to 1.0-cm nodules) were the only no
dules of this size in 7 subjects. Of 11 nodules 1.5 cm or larger, only
5 were palpable. Serum thyroglobulin correlated to the number (P = 0.
04; r(2) = 0.10), but not the volume of the thyroid nodules (P = 0.07;
r(2) = 0.08). We conclude that thyroid nodules are continuing to occu
r and are exceedingly common in this irradiated cohort of individuals.
The results confirm that thyroid ultrasonography is more sensitive th
an physical examination and scanning. However, thyroid ultrasound is s
o sensitive and nodules so prevalent that great caution is needed in i
nterpreting the results.