Fine needle aspiration of thyroid nodules in a general teaching hospital setting performing moderate number of biopsies: outcome of indeterminate cytologic results

Abstract

Introduction: Our aim was to assess the usefulness of fine-needle aspiration cytologic biopsy (FNA) of the thyroid in our general teaching hospital with average health care facility performing moderate number of such procedures and to evaluate the outcome of Indeterminate Cytologic Results.
Material and methods: We studied on all consecutive patients referred for FNA of the thyroid nodule. All samplings were performed primarily by one endocrinologist performing moderate number of samplings and interpreted by one pathologist. Cytological findings were classified as malignant, histologic control recommended (suspicious or indeterminate), benign, and unsatisfactory.
Results: Four hundred and seventy six biopsies were performed. Patient acceptance of this procedure was good and no complication was encountered. 64/476 of samples were considered as insufficient (13.4%). Of the remaining samples (355 F, 57 M), 321 specimens (67.4%) were reported to be non-neoplastic lesions, including 251 (52.7%) colloid nodules, 39 (8.2%) hemorrhagic nodules and 31 (6.5%) cases of thyroiditis. A neoplastic nodule was confirmed in 91/476 of cases (19.1%), of which 14 were cytologically malignant (3.0%). Follicular lesions were identified in the remaining 77/476 cases (16.1%). Excluding 21 patients who were lost to follow-up, the remaining 56 patients (72.7%) were surgically followed up. Upon excision, benign lesions were diagnosed in 47/56 (83.8%), of which 32 lesions (57.1%) were follicular adenoma and 15 cases (26.7%) of colloid nodules. Malignancy was confirmed histopathologically in 9 cases (16.2%), including 4 follicular variant papillary carcinomas and 5 follicular carcinomas.
Conclusions: FNA is an inexpensive, safe, practical, well tolerated, and easily applied method, even in not fully-experienced hands and provides useful information. Based on our study findings, suspicious cytologic results (cytologically follicular neoplasms) are inconclusive and are associated with a remarkable chance of malignant involvement; hence surgical treatment is necessary for clarification. (Pol J Endocrinol 2008; 59 (5): 385-389)