Malignancy risk of thyroid nodules with minimal cystic changes: a multicenter retrospective study

Purpose@#The aim of this multicenter study was to investigate the malignancy risk of minimally cystic thyroid nodules (MCTNs) using cyto-histopathologic diagnoses as the reference standard. @*Methods@#From June 2015 to September 2015, 5,601 thyroid nodules (≥1 cm) from 4,989 consecutive patients who underwent thyroid ultrasonography (US) at 26 institutions were retrospectively analyzed. Each thyroid nodule was categorized according to its cystic proportion: purely solid, minimally cystic (≤10%), and partially cystic (>10%). The malignancy risk of MCTNs was compared with those of purely solid nodules and partially cystic thyroid nodules (PCTNs). The malignancy risk of MCTNs was assessed according to echogenicity and the presence of suspicious US features. @*Results@#The prevalence of MCTNs was 22.5%. The overall malignancy risk of MCTNs was 8.8%, which was significantly lower than that of purely solid nodules (29.5%) (P0.05). MCTNs were associated with a higher risk of malignancy in hypoechoic nodules than in isohyperechoic nodules and in nodules with suspicious US features than in those without suspicious US features (all P<0.001). @*Conclusion@#The malignancy risk of MCTNs was significantly lower than that of purely solid nodules. MCTNs could be categorized as PCTNs rather than as solid nodules to increase the accuracy of the risk stratification system for thyroid nodules.

Kikuchi-Fujimoto Disease Masquerading as Bilateral Lymph Node Metastasis in a Patient With Papillary Thyroid Carcinoma: A Case Report and Literature Review / 대한이비인후과학회지

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is common in young Asian women under the age of 30, and is usually characterized by fever, myalgia, fatigue, and cervical lymphadenopathy. Because patients with KFD often present with necrotic lesions that are also features of lymph node metastasis, ipsilateral or bilateral lymph node enlargement in head and neck cancer patients can be disguised as lymph node metastasis. We present an unusual case of KFD mimicking bilateral metastatic papillary carcinoma of the thyroid. This study emphasizes that KFD should be considered when diagnosing lymph nodes with necrotic lesions but without malignant cells in young women.

High-Resolution Magnetic Resonance Imaging Findings of Reversible Cerebral Vasoconstriction Syndrome associated with Severe Anemia: A Case Report

Ischemic stroke is one of the manifestations of reversible cerebral vasoconstriction syndrome (RCVS). Many precipitants and associated disorders of RCVS have been suggested. However, few case reports have indicated an association between anemia and RCVS. Here, we report a case of a 66-year-old female with severe iron deficiency anemia (IDA), who presented with ischemic stroke and cerebral vasoconstriction, which gradually improved with conservative treatment. High-resolution vessel wall magnetic resonance imaging findings and reversibility suggested the possibility of RCVS. In patients with RCVS and ischemic stroke, IDA should be considered. Prompt management should be delivered to prevent disease progression and recurrence.

Ultrasonographic Features and the Diagnostic Role of Core Needle Biopsy at Metastatic Breast Cancer in the Thyroid gland: A Case Report

Metastases to the thyroid gland have rarely been reported in clinical settings, and the thyroid gland is an uncommon site for breast carcinoma metastasis. We report a case of a 64-year-old breast cancer patient diagnosed with metastatic breast carcinoma in the thyroid gland after performing ultrasonography (US)-guided core needle biopsy (CNB) and subsequent total thyroidectomy. On US, the thyroid lesion appeared to be mildly enlarged with multiple internal hypoechoic lines and a few microcalcifications without mass formation. Under US-guidance, CNB was performed by targeting the area with microcalcifications and subsequently diagnosed as metastatic breast carcinoma. Total thyroidectomy revealed that the patient had metastatic invasive ductal carcinoma of the breast with lymphatic spread involving both lobes and the isthmus of the thyroid gland. Although the thyroid gland is an uncommon metastatic site, the unusual features of thyroid metastasis can be observed on US; thus, US-guided CNB effectively aids the diagnosis of thyroid metastasis.

Superficially Palpable Masses of the Scalp and Face: A Pictorial Essay

Palpable lesions of the scalp and face are common in clinical practice. They are usually small and benign, and the lesions tend to be treated simply according to the clinical symptoms. However, radiologic evaluation is often performed to determine the exact type and location of a lesion to ensure appropriate management. Ultrasonography is useful as a primary and definitive modality for evaluating small superficial lesions. CT and MRI are better for characterizing soft tissue features and provide superior soft tissue resolution. This article discusses various lesions and their imaging findings of the scalp and face that may present as superficially palpable masses.

Papillary Thyroid Carcinoma with Retropharyngeal Node Metastasis Demonstrating Negative I-131 but Positive FDG Uptake on PET/CT / 대한내분비외과학회지

Papillary thyroid carcinoma (PTC) is commonly accompanied by cervical lymph node metastasis, whereas metastases to the retropharyngeal lymph nodes (RPN) are rare. Radioactive iodine (RAI) ablation is recommended for detection and treatment of differentiated thyroid carcinoma (DTC). However, in some cases of iodine-negative DTC, F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) can aid in detection of additional lesions. We report on a patient with PTC who had retropharyngeal node involvement with iodine-negative features and low thyroglobulin level at the time of diagnosis but with metastasis identified on FDG PET/CT.

Intravoxel Incoherent Motion MR Imaging in the Head and Neck: Correlation with Dynamic Contrast-Enhanced MR Imaging and Diffusion-Weighted Imaging

OBJECTIVE: To investigate the correlation between perfusion- and diffusion-related parameters from intravoxel incoherent motion (IVIM) and those from dynamic contrast-enhanced MR imaging (DCE-MRI) and diffusion-weighted imaging in tumors and normal muscles of the head and neck. MATERIALS AND METHODS: We retrospectively enrolled 20 consecutive patients with head and neck tumors with MR imaging performed using a 3T MR scanner. Tissue diffusivity (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) were derived from bi-exponential fitting of IVIM data obtained with 14 different b-values in three orthogonal directions. We investigated the correlation between D, f, and D* and model-free parameters from the DCE-MRI (wash-in, Tmax, Emax, initial AUC60, whole AUC) and the apparent diffusion coefficient (ADC) value in the tumor and normal masseter muscle using a whole volume-of-interest approach. Pearson's correlation test was used for statistical analysis. RESULTS: No correlation was found between f or D* and any of the parameters from the DCE-MRI in all patients or in patients with squamous cell carcinoma (p > 0.05). The ADC was significantly correlated with D values in the tumors (p 0.05, respectively). CONCLUSION: Intravoxel incoherent motion shows no significant correlation with model-free perfusion parameters derived from the DCE-MRI but is feasible for the analysis of diffusivity in both tumors and normal muscles of the head and neck.

Superior Cervical Sympathetic Ganglion: Normal Imaging Appearance on 3T-MRI

OBJECTIVE: To identify superior cervical sympathetic ganglion (SCSG) and describe their characteristic MR appearance using 3T-MRI. MATERIALS AND METHODS: In this prospective study, we recruited 53 consecutive patients without history of head and neck irradiation. Using anatomic location based on literature review, both sides of the neck were evaluated to identify SCSGs in consensus. SCSGs were divided into definite (medial to internal carotid artery [ICA] and lateral to longus capitis muscle [LCM]) and probable SCSGs based on relative location to ICA and LCM. Two readers evaluated signal characteristics including intraganglionic hypointensity of all SCSGs and relative location of probable SCSGs. Interrater and intrarater agreements were quantified using unweighted kappa. RESULTS: Ninety-one neck sites in 53 patients were evaluated after exclusion of 15 neck sites with pathology. Definite SCSGs were identified at 66 (73%) sites, and probable SCSGs were found in 25 (27%). Probable SCSGs were located anterior to LCM in 16 (18%), lateral to ICA in 6 (7%), and posterior to ICA in 3 (3%). Intraganglionic hypointensity was identified in 82 (90%) on contrast-enhanced fat-suppressed T1-weighted images. There was no statistical difference in the relative location between definite and probable SCSGs of the right and left sides with intragnalionic hypointensity on difference pulse sequences. Interrater and intrarater agreements on the location and intraganglionic hypointensity were excellent (κ-value, 0.749-1.000). CONCLUSION: 3T-MRI identified definite SCSGs at 73% of neck sites and varied location of the remaining SCSGs. Intraganglionic hypointensity was a characteristic feature of SCSGs.

Primary Endobronchial Marginal Zone B-Cell Lymphoma of Bronchus-Associated Lymphoid Tissue: CT Findings in 7 Patients

OBJECTIVE: To investigate CT and 18F-flurodeoxyglucose (18F-FDG) positron-emission tomography/CT findings of primary endobronchial marginal zone B-cell lymphoma of the bronchus-associated lymphoid tissue (BALT). MATERIALS AND METHODS: From June 2006 through April 2012, seven patients (six female, one male; age range, 21-61 years; mean age, 49 years) were examined who were pathologically diagnosed with the primary endobronchial marginal zone B-cell lymphoma of BALT. We evaluated the locations and characteristics of the lesions on CT and 18F-FDG-PET/CT scans. The lesions were classified into the following three patterns: 1) solitary intraluminal nodule; 2) several tiny nodular protrusions; and 3) diffuse wall thickening. RESULTS: A solitary intraluminal nodule was observed in four patients (57.1%), several tiny nodular protrusion in two patients (28.6%), and diffuse wall thickening in one patient (14.3%). The lesions were categorized into 3 major locations: confined to the trachea (n = 3), confined to the lobar bronchus (n = 2), and diffuse involvement of the trachea and both main bronchi (n = 2). All lesions demonstrated homogeneous iso-attenuation as compared with muscle on pre- and post-enhancement scans. Secondary findings in the lungs (n = 3; 42.9%) included postobstructive lobar atelectasis (n = 1), air trapping (n = 1), and pneumonia (n = 1). On 18F-FDG-PET/CT (n = 5), 4 lesions showed homogeneous uptake with maximum standardized uptake values (mSUV), ranging 2.3-5.7 (mean mSUV: 3.3). One lesion showed little FDG uptake. CONCLUSION: Primary endobronchial marginal zone B-cell lymphoma of the BALT manifests as three distinct patterns on CT, with the solitary intraluminal nodule presenting as the main pattern. Most lesions demonstrate homogeneous but weak FDG uptake on 18F-FDG-PET/CT.