16
Maternal Disorders
Table 2. ATA Sonographic Patterns and Estimated Risk of
Malignancy for Thyroid Nodules
(Adapted om ATA 2015 Guidelines with Permission)
Sonographic
Pattern Ultrasound features
Estimated
risk of
malignancy
FNA Size cutoff
(largest
dimension)
High suspicion Solid hypoechoic nodule or
solid hypoechoic component
of a partially cystic nodule with
one or more of the following
features: irregular margins
(infiltrative, microlobulated),
microcalcifications, taller than
wide shape, rim calcifications
with small extrusive so
tissue component, evidence of
extrathyroidal extension
>70–90% Recommend at
>1 cm
Intermediate
suspicion
Hypoechoic solid nodule
with smooth margins
without microcalcifications,
extrathyroidal extension, or
taller than wide shape
10–20% Recommend at
>1 cm
Low suspicion Isoechoic or hyperechoic
solid nodule, or partially
cystic nodule with eccentric
solid areas, without
microcalcification, irregular
margin or extrathyroidal
extension, or taller than wide
shape
5–10% Recommend at
>1.5 cm
Very low
suspicion
Spongiform or partially cystic
nodules without any of the
sonographic features described
in low, intermediate or high
suspicion patterns
<3% Consider at >2 cm
Observation
without FNA is
also a reasonable
option
Benign Purely cystic nodules (no solid
component)
<1% No biopsy
