Clinical Features Associated with an Increased Risk of Malignancy in Indeterminate Group by Find Needle Aspiration of Thyroid Nodules / 대한내분비학회지

ABSTRACT

BACKGROUND: The recommended management of patients who have cytologic diagnosis of indeterminate group by fine fine needle aspiration (FNA) in thyroid nodules is controversial. Our objective was to identify the incidence of malignancy through thyroidectomy in indeterminate group and clinical features associated with an increased risk of malignancy that might guide future practice. METHODS: We retrospectively reviewed the medical records of 222 patients who had cytologic diagnosis of indeterminate group by FNA in thyroid nodules at Seoul National University Hospital from Jan. 1990 to Aug. 1998. Patients characteristics and clinical features were compared between benign and malignant nodules classified as pathologic findings through thyroidectomy. RESULTS: The frequency of indeterminate group was 6% (222/3981) among patients underwent thyroid FNA. The frequency of malignant nodules was 47.4% (64/135) among 135 patients underwent thyroidectomy. Among clinical features, rapid increase in size (7.0% vs 20.3%, p=0.024), local symptoms such as dysphagia, hoarseness, pain (1.4% vs 15.6%, p=0.003), fixation (4.4% vs 35.7%, p<0.001), hard consistency(15.7% vs 59.7%, p<0.001) and irregular surface(6.3% vs 25.6%, p=0.001) were significantly more common in malignant nodules than in benign nodules. However, clinical features such as mean age of patients, male sex, presence of past history of benign thyroid disease, family history of benign thyroid disease, solitary nodule, presence of cervical lymph nodes, mean size of nodules and cold nodules by thyroid scan in malignant nodules were not significantly different from that in benign nodules. Among clinical features that were significantly more common in malignant nodules, fixation(p=0.042) and presence of local symptoms (p=0.043) were significantly independent risk factors predictive of malignancy. CONCLUSION: Its better to recommend thyroidectomy in patients with clinical features such as presence of local symptoms, fixed nodule and hard nodule in indeterminate group, in otherwise to decide treatment with repeated FNAs when clinical features such as patients symptoms and physical examinations of nodule change through regular follow-up.