Ultrasound sensitivity for thyroid malignancy is increased by real-time elastography: a prospective multicenter study.
BACKGROUND
Thyroid nodules are selected for biopsy on the basis of clinical and ultrasound (US) findings. Ultrasonography detects nodules at risk of malignancy, but its diagnostic accuracy does not rule out with certainty the possibility of cancer in lesions without suspicious findings.


OBJECTIVE
The objective of the study was to evaluate the diagnostic accuracy of real-time elastography (RTE) in thyroid nodules and to assess the improvement provided by combination of RTE, B-mode US, and color flow Doppler (CFD).


METHODS
This was a prospective multicenter study.


METHODS
A consecutive series of 498 thyroid nodules was blindly evaluated by US, CFD, and RTE before biopsy or surgery. Nodules were classified at RTE by four-class color scale. Patients with benign cytology underwent follow-up over 12 months, whereas patients with indeterminate, suspicious, or malignant cytology were surgically treated.


RESULTS
At follow-up, 126 nodules were malignant and 372 benign. RTE classes III-IV showed 81% sensitivity and 62% specificity. The presence of at least one US risk factor (hypoechogenicity, microcalcifications, irregular margins, intranodular vascularization, and taller than wide shape) had 85% sensitivity and 91% negative predictive value. When RTE was combined with US, the presence of at least one of the six parameters had 97% sensitivity and 97% negative predictive value, with an odds ratio of 15.8 (95% confidence interval 5.7-43.8).


CONCLUSIONS
RTE is a valuable tool for detecting malignant thyroid lesions with a sensitivity similar to traditional US and CFD features. By adding RTE evaluation, the sensitivity for malignancy of US findings is markedly increased and the selection of nodules that do not need cytology is made more reliable.
Section of Endocrinology and Diabetology, Ospedale Israelitico, 00148 Rome, Italy.
Pierpaolo
P
Trimboli
Rinaldo
R
Guglielmi
Salvatore
S
Monti
Irene
I
Misischi
Filomena
F
Graziano
Naim
N
Nasrollah
Stefano
S
Amendola
Sara Nazzarena
SN
Morgante
Maria Grazia
MG
Deiana
Stefano
S
Valabrega
Vincenzo
V
Toscano
Enrico
E
Papini
D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D003199:Computer Systems; D003937:Diagnosis, Differential; D054459:Elasticity Imaging Techniques / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D016606:Thyroid Nodule / Q000145:classification / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology