Management of isolated thyroid swellings: a prospective six year study of fine needle aspiration cytology in diagnosis.
OBJECTIVE
To audit the accuracy and impact on the frequency of operation of fine needle aspiration cytology of isolated thyroid swellings.


METHODS
Prospective analysis over six years of cytological predictions compared with histological findings.


METHODS
Thyroid clinic serving the Grampian region.


METHODS
395 Consecutive patients presenting with an isolated thyroid swelling, 307 of whom underwent surgical excision. Analysis was confined to a subgroup of 283 patients with satisfactory aspirates who were operated on.


RESULTS
The positive predictive value of aspiration cytology for detecting malignant disease was 100% and the sensitivity 83%. The sensitivity for the detection of neoplasia (frank malignancy together with follicular adenomas) was 76%. The specificity was 58% and the overall accuracy 69%. Recalculation of data in previous papers with strict criteria showed the accuracy of aspiration cytology to be variable and lower than is widely accepted. Since the introduction of aspiration cytology 21% fewer operations for isolated thyroid swellings have been performed.


CONCLUSIONS
As a basis of selection for surgical excision of isolated thyroid swellings according to prediction of neoplasia fine needle aspiration cytology is less reliable than is widely accepted. It is an adjunct to management rather than a definitive test, and negative cytological results do not exclude neoplastic disease. Further study should take account of the implications of repeated clinic attendances for review and aspiration as these may culminate in delayed surgical treatment.
Department of Surgery, University of Aberdeen, Foresterhill.
E L
EL
Cusick
C A
CA
MacIntosh
Z H
ZH
Krukowski
V M
VM
Williams
S W
SW
Ewen
N A
NA
Matheson
D001707:Biopsy, Needle; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013959:Thyroid Diseases / Q000175:diagnosis / Q000473:pathology; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery