J Korean Soc Endocrinol.  1999 Mar;14(1):71-80.

The Diahnostic Value of Ultrasound-Guided Fine Needle Aspiration Cytology in the Thyroid Indedentaloma

• Choi YS
• Kwon K
• Kim SM
• Park YH
• Oh KS
• Seo JY
• Chun BK
• Chang HK

Abstract

BACKGROUND
The introductian of highly sensitive imaging techniques has made it possible to detect many nonpalpable nodules, or incidentaloma. Because these nodules are small sized or deep seated, the diagnostic approach is difficult with conventional methods but it is easy with ultrasound-guided fine needle aspiration (FNA). However, the role of ultrasound-guided FNA on the incidentalomas has been poorly evaluated, so we tried to assess the diagnostic value of high resolution ultrasound-guided FNA in the incidentalomas.
METHODS
One hundred forty-nine patients who underwent high resolution ultrasound-guide FNA for nonpalpable nodules that was smaller than 1.5 cm in diameter at Kosin Medical Center from June, 1996 to April, 1998 were included in the study. Ultrasound-guided FNA was performed with a 22-guage needle attached to 10 mL syringe with 10 MHz linear transducer in a free hand fashion. The aspirated materials were smeared and stained with Papanicolaou stain. For those who underwent surgery histopathologic diagnoses were compared to cytological diagnoses.
RESULTS
The mean age of the patients was 45 and most of them were middle aged. Male to female ratio was 1:11.4. Of 149 patients 16 were involutional change, 55 hyperplasia, 42 Hashimotos thyroiditis, 8 follicular neoplasm, 19 papillary carcinoma, 1 subacute thyroiditis, and 6 inadequate specimen. Of the 149 nodules, 123 cases were solid, 11 cystic, and 15 mixed. Malignant nodules were more frequent in the solid nodule, but there was no significant difference between each group. Ten of 93 cases (10.7%) measured less than 1 cm and nine of 56 cases (16.1%) between 1.0 cm to 1,5 cm were malignant nodules. The difference of incidence rate of malignant nodules between each group was not significant. The incidence of malignancy was 13.6% (12/88) in solitary nodule and 11.5% (7/61) in multiple nodules. The difference of incidence rate of malignant nodules between each group was not significant. Eighteen cases including 14 malignancies diagnosed by FNA underwent operation. Of those 13 were papillary carcinoma and 5 adenomatous goiter. Upon the correlation of ultrasound-guided FNA cytology with pathologic diagnosis, the sensitivity of ultrasound-guided FNA cytology in differentiating benign and malignant nodule was 92.3% and overall diagnostic accuracy was 80.0%. The obtainability of adequate cytologic specimen by ultrasound-guided FNA was 95.9%. No complication except pain was noted during this study.
CONCLUSION
High resolution ultrasound-guided FNA cytology may be useful for the diagnosis of thyroid cancer in the thyroid incidentalomas and also useful for early detection of recurrence of thyroid cancer .

MeSH Terms

Biopsy, Fine-Needle*
Carcinoma, Papillary
Diagnosis
Female
Goiter
Hand
Humans
Hyperplasia
Incidence
Male
Middle Aged
Needles
Recurrence
Syringes
Thyroid Gland*
Thyroid Neoplasms
Thyroid Nodule
Thyroiditis
Thyroiditis, Subacute
Transducers