Interpretation of the Paucicellular Thyroid Fine Needle Aspiration Biopsy Specimen:

Fine needle aspiration cytology of thyroid lesions and its correlation with histopathology in a series of 248 patients

Thyroid swellings are a significant clinical problem in the general population but majority of them are nonneoplastic and do not require surgery. The initial screening procedures include ultrasonography, fine needle aspiration cytology (FNAC) and radionucleotide scan. An initial screening test which will diagnose thyroid lesions accurately will help to avoid surgery in nonneoplastic conditions. The aim of the present study is to correlate the cytology findings with final histopathology. Two hundred and forty-eight cases of thyroid nodules which underwent FNAC followed by surgery were included in this study. The cytology diagnoses were classified into nondiagnostic/unsatisfactory, benign, atypia of undetermined significance/follicular lesion of undetermined significance, follicular neoplasm/suspicious for a follicular neoplasm, suspicious for malignancy and malignant. The fine needle aspiration diagnosis was compared with the histopathology diagnosis. In majority of cases the FNA diagnosis was in concordance with final histopathology. A high incidence of follicular variant of papillary carcinoma thyroid was detected in this study. The awareness of this entity and the search for fine nuclear details of papillary carcinoma can lead to proper identification of this category of tumors and thus help to avoid false negative and equivocal results. Fine needle aspiration cytology is a simple, cost effective, rapid to perform procedure with high degree of accuracy and is recommended as the first line investigation for the diagnosis of thyroid lesions.

Rapid on-site evaluation of fine needle aspiration specimens by cytology scientists: a review of 3032 specimens

OBJECTIVES

To determine: (1) the accuracy of cytology scientists at assessing specimen adequacy by rapid on-site evaluation (ROSE) at fine needle aspiration (FNA) cytology collections; and (2) whether thyroid FNA with ROSE has lower inadequacy rates than non-attended FNAs.

METHODS

The ROSE of adequacy for 3032 specimens from 17 anatomical sites collected over a 20-month period was compared with the final report assessment of adequacy. ROSE was performed by 19 cytology scientists. The report profile for 1545 thyroid nodules with ROSE was compared with that for 1536 consecutive non-ROSE thyroid FNAs reported by the same cytopathologists during the study period.

RESULTS

ROSE was adequate in 75% (2276/3032), inadequate in 12% (366/3032) and in 13% (390/3032) no opinion was rendered. Of the 2276 cases assessed as adequate by ROSE, 2268 (99.6%) were finally reported as adequate for assessment; eight specimens had adequacy downgraded on the final report. Fifty eight per cent of cases with a ROSE assessment of inadequate were reported as adequate (212/366), whereas 93% (363/390) with no opinion rendered were reported as adequate. The overall final report adequacy rate for the 3032 specimens was 94% (2843/3032). Confirmation of a ROSE of adequacy at reporting was uniformly high amongst the 19 scientists, ranging from 98% to 100%. The inadequacy rate for thyroid FNAs with ROSE (6%) was significantly (P < 0.0001) lower than for non-ROSE thyroid FNAs (17%). A significantly (P = 0.02) higher proportion of adequate ROSE thyroid specimens was reported with abnormalities, compared with non-ROSE thyroid collections.

CONCLUSIONS

Cytology scientists are highly accurate at determining specimen adequacy at ROSE for a wide range of body sites. ROSE of thyroid FNAs can significantly reduce inadequate reports.