Predictive Factors of Malignancy in Cytology of Indeterminate Follicular and Hürthle Cell Neoplasms of the Thyroid Gland

Abstract

The objective of the current study was to determine the risk of malignancy in patients with thyroid nodules with cytology of indeterminate follicular and indeterminate Hürthle cell neoplasm (HN). The cytologic diagnosis of follicular neoplasm (FN) or HN remains a diagnostic challenge. Often, surgery is recommended for such lesions. A retrospective analysis was performed on 80 patients who underwent thyroid surgery following a diagnosis of indeterminate FN and indeterminate HN in thyroid fine-needle aspiration biopsy. Sex; age; family history of thyroid cancer and radiation exposure; coexisting thyroid conditions, such as solitary nodule; multinodularity; cytologic diagnosis; sonographic features; type of surgical treatment; and histopathologic results were recorded. Of the 80 patients, 52 (65%) had FN on fine-needle aspiration biopsy cytology and 28 (35%) had HN. A total of 23 patients (28.7%) had primary thyroid cancers on surgical pathology, and 57 (71.3%) had benign diagnoses. Univariate analysis showed no differences between the benign and malignant groups by sex, nodule size, family history of thyroid cancer, history of radiation exposure, presence of solitary nodule or multinodularity in the nodular features. In multivariate binary logistic regression analysis, the factors that were statistically significant predictors of malignancy were microcalcification [odds ratio (OR), 10.9; 95% confidence interval (CI), 2.18–54.7; P = 0.004], being older than 45 years (OR, 4.2; 95% CI, 1.25–14.63; P = 0.02]. The independent predictors of malignancy in FN and HN are micorcalcification and being older than 45 years, the use of which may predict the risk of thyroid cancer.

Rate and Clinical Predictors of Malignancy in Thyroid Nodules with Indeterminate Cytology

“…The risk of malignancy is thought to be higher in these lesions compared to follicular neoplasms [12] . But this is challenged by others [13,14] . Hurthle cells can be found in different reactive, inflammatory, and neoplastic processes of the thyroid.…”

“…Common biopsy findings after thyroidectomy for cytologically indeterminate thyroid lesions include Follicular adenoma, adenomatoid hyperplasia, follicular carcinoma, follicular variant of papillary cancer, and classical papillary cancer [8,9,15] . The incidence of malignancy in cytologically indeterminate nodules ranges from 14% to 48.5% [8,9,13,15] . The incidence of malignancy in the present study was 22.4%; which is comparable with most of the reports.…”