Thyroid cancer in hyperthyroidism: Incidence rates and value of ultrasound-guided fine-needle aspiration biopsy in this patient group

Abstract

Three hundred and thirty-three hyperthyroidism cases were retrospectively investigated to provide information about the association between hyperthyroidism and thyroid cancer. There were 112 cases of toxic multinodular goiter (TMNG), 77 cases of toxic nodular goiter (TNG) and 144 cases of Graves' disease (GD). All nodules detected in GD patients, all nodules greater than 1 cm diameter in nodular goiter patients, nodules 5-10 mm size diameter if they had calcification were fine-needle biopsied (FNAB) under ultrasound guidance (US-guided), and a total of 612 such biopsies were performed. The biopsy samples were cytologically assessed as benign (no.=552; 90.2%), suspicious (no.=6; 1.1%), malignant (no.=13; 2.1%), or inadequate for diagnosis (no.=41; 6.7%). All patients with a biopsy diagnosis of malignant or suspicious nodules underwent surgery. Histological examination confirmed the diagnosis of thyroid cancer in all 13 (2.1%) patients with malignant FNAB findings. Papillary thyroid carcinoma (PTC) was identified in 2 patients with TMNG (%1.8), 5 with TNG (%6.5) and 5 with GD (%3.5). Metastatic follicular thyroid carcinoma (FTC) was identified in a patient with TNG. Thyroid malignancy (micro- or macrocarcinoma) was diagnosed pre-operatively in all 13 cases by US-guided FNAB. Thyroid cancer was diagnosed in 6 (5.5%) of the 109 nodules detected in the TNG group, 2 (0.44%) of the 452 nodules detected in the TMNG group, and 5 (9.8%) of the 51 nodules detected in the GD group. Two (2.6%) of the 77 functioning nodules in the TNG patients were malignant, but none of the 402 functioning nodules in the TMNG patients was malignant. In patients with hyperthyroidism, US-guided FNAB is useful for detecting thyroid cancer in nodules greater than 5 mm diameter before radioiodine therapy or surgery.

Thyroid Cancer in Patients with Hyperthyroidism

“…It is important to perform thyroid and neck US and US-guided FNAC prior to radioiodine therapy or thyroidectomy [ 16 ] , in order to detect thyroid cancer. US-FNAC should be focused on lesions, which appear suspicious by US features as stated by the Consensus of Society of Radiologists in Ultrasound [ 55 , 106 ] , and not on larger or clinical dominant nodules.…”

Role of Apparent Diffusion Coefficient Values in Differentiation Between Malignant and Benign Solitary Thyroid Nodules

“…The challenge of imaging thyroid nodules is to reassure most patients who have benign disease and to diagnose the minority of patients who will prove to have a malignancy. 5,6 Ultrasonography has been used in the assessment of the thyroid nodules as a primary imaging technique. 2,7,8 Currently, there is no single sonographic criterion that can reliably distinguish benign from malignant thyroid nodules.…”

ADC Values in Distinction of Benign and Malignant Thyroid Nodules

“…Most coomonly found benign nodules are adenomatous nodules and the remaining of them can be counted as adenomas, cysts and thyroiditis. 2,4,8,10 The frequency of malignant thyroid nodules relatively low and reported around 5%. In our study, the incidence of benign nodules was 70.2% and those of malignant ones was 29.8 %.…”

“…8,9 Nuclear scintigraphy has risk of radiation exposure and not all hot or hyperfunctioning nodules detected on scintigraphy are benign. 10,11 Malignancy risk for cold nodule is four times more common compared with a hot nodüle. 3,10 The importance of conventional magnetic resonance imaging (MRI) is evaluating the deep placed nodules and presence of distant metastases where USG might remain insufficient.…”

“…10,11 Malignancy risk for cold nodule is four times more common compared with a hot nodüle. 3,10 The importance of conventional magnetic resonance imaging (MRI) is evaluating the deep placed nodules and presence of distant metastases where USG might remain insufficient. DWI The aim of our study was to evaluate the role of ADC values in the differentiation of benign and malignant thyroid nodules using histopathological results obtained with surgery as a reference standard.…”