Diagnostic efficacy of conventional as compared to liquid-based cytology in thyroid lesions: evaluation of 10,360 fine needle aspiration cytology cases.
OBJECTIVE
To evaluate the efficacy of thyroid fine needle aspiration cytology (FNAC) processed by liquid-based cytology (LBC) as compared to conventional smears (CS) in 10,360 consecutive cases in 3 reference periods.


METHODS
In 1997-1998, 2,394 FNACs had CS; in 2001-2002, 3,463 had both CS and LBC; and in 2004-2005, 4,503 had only LBC. Three arbitrary parameters of efficacy were chosen to compare the two different methods: rate of inadequacy (IR), rate of indeterminacy (INDR) and rate of malignancy (MR). In the same biennia 6,184 thyroidectomy specimens were examined.


RESULTS
IR was, respectively, 8.4% in 1997-1998, 18.4% in 2001-2002 and 13.3% in 2004-2005. MR was respectively 2.2%, 2.5% and 2.2%. INDR was 16.6% in 1997-1998, 23.3% in 2001-2002 and 15.9% in 2004-2005. In each biennium, respectively, 16.9%, 27.6% and 28% of malignant neoplasms were histologically diagnosed.


CONCLUSIONS
LBC was used as an alternative method in the cytologic diagnosis for the preoperative selection of thyroid neoplasms, decreasing indeterminate diagnoses without MR changes.
Rossi
Esther Diana
ED
Division of Anatomic Pathology, Catholic University of Sacred Heart, Rome, Italy.
Raffaelli
Marco
M
Zannoni
Gian Franco
GF
Pontecorvi
Alfredo
A
Mulè
Antonino
A
Callà
Cinzia
C
Lombardi
Celestino Pio
CP
Fadda
Guido
G
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle / Q000379:methods*; D002291:Carcinoma, Papillary / Q000175:diagnosis / Q000473:pathology; D002648:Child; D003584:Cytological Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012015:Reference Standards; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D055815:Young Adult