No abstract available.

No abstract available.
Thyroid Gland* ; Thyroid Neoplasms*

Differentiated thyroid cancer is usually a curable disease, for which treatment modalities such as surgery, radioiodine, and thyroid hormone have been used for the last 50 years, yet little consensus has been established due to the lack of prospective randomized controlled therapeutic trials. After an initial surgery, the patients' outcome can be predicted by staging classification on the basis of several parameters such as the age of the patient, tumor size, tumor grade or differentiation, presence of local invasion, and regional or distant metastases. However, regardless of the pathologic stage, most patients(except those with micopapillary or minimally invasive follicular carcinomas who underwent only a lobectomies) are supposed to receive radioiodine therapy for ablation of any remnant thyroid tissue, which increases the sensitivity of serum Tg and 131I whole body scan used to detect recurrence or metastasis during a long-term follow-up. Until recently, a high dose of 131I has been preferred, however, low dose therapy(30mCi) is a new trend nowadays, which decreases the incidence of both acute and late complications of radioiodine with the same ablation rate. All patients take thyroid hormone after surgery and radioremnant ablation to suppress the level of serum TSH, which is thought to stimulate tumor cell growth.The T4 dose should be adjusted according to the age of the patient, other medical conditions and the risk of recurrence. During the follow-up, the serum Tg level with anti-Tg antibody and the TSH level and 131I whole body scan should be checked regularly. Recently the serum Tg level stimulated by T4 withdrawal or rhTSH injection is suggested to be the most sensitive marker for the detection of recurrence or metastasis. When the stimulated Tg is undetectable (< 2ng/mL), residual or metastatic cancer can be nearly excluded; when it is higher than 10ng/mL, a high dose 131I therapy and posttherapy 131I whole body scan are needed. In cases where the localization fails(Tg-positive/131I scan-negative cases), other imaging studies such as high-resolution ultrasonography of the neck, spiral CT of chest, bone X-ray or 99mTc-MDP bone scan and 18F-FDG PET scan can be useful. 18F-FDG PET is especially sensitive to detect poorly differentiated thyroid cancers that have lost the ability to uptake radioiodine.
Classification ; Consensus ; Fluorodeoxyglucose F18 ; Follow-Up Studies* ; Humans ; Incidence ; Neck ; Neoplasm Metastasis ; Positron-Emission Tomography ; Recurrence ; Technetium Tc 99m Medronate ; Thorax ; Thyroid Gland ; Thyroid Neoplasms* ; Thyrotropin Alfa ; Tomography, Spiral Computed ; Ultrasonography ; Whole Body Imaging

Graves’ disease is the most common cause of hyperthyroidism which is caused by stimulating autoantibodies against thyroid-stimulating hormone receptor. There is no etiology-specific treatment for Graves’ disease.Current Concepts: Graves’ disease can be treated with antithyroid drugs (ATDs), radioactive iodine, or thyroidectomy. ATDs are the most preferred first-line therapy, because they do not cause either permanent hypothyroidism or exacerbation of orbitopathy, despite low remission rate. ATDs have serious adverse reactions including agranulocytosis and fulminant hepatic necrosis requiring liver transplantation. Methimazole (MMI) is recommended in every patient starting ATD therapy, except during the first trimester of pregnancy and in cases of thyroid storm, because of relatively lower incidence and severity of serious adverse reactions compared with propylthiouracil. Treatment should be continued for 12 to 18 months, then discontinued if the levels of thyroid-stimulating hormone and thyroid-stimulating hormone receptor antibodies are normalized. In cases of relapse of hyperthyroidism, radioactive iodine or thyroidectomy can be recommended for definitive therapy; however, recent studies support longer-term maintenance of low dose MMI as a favorable alternative therapy. All ATDs may induce congenital anomalies when exposed during early pregnancy. Every female patient of reproductive age should be advised to postpone pregnancy until their thyroid function is maintained within normal range and to stop ATDs when pregnancy is confirmed to avoid the risk of congenital anomalies.Discussion and Conclusion: Longer-term low dose MMI therapy can be a good choice for Graves’ hyperthyroidism with relapse. Before pregnancy, hyperthyroidism should be controlled to stop ATDs during pregnancy.

Thyroid hormone plays a critical role in fetal growth and development, and thyroid dysfunction during pregnancy is associated with several adverse outcomes, such as miscarriage and preterm birth. In this review, we introduce and explain three major changes in the revised Korean Thyroid Association (KTA) guidelines for the diagnosis and management of thyroid disease during pregnancy: first, the normal range of thyroid-stimulating hormone (TSH) during pregnancy; second, the treatment of subclinical hypothyroidism; and third, the management of euthyroid pregnant women with positive thyroid autoantibodies. The revised KTA guidelines adopt 4.0 mIU/L as the upper limit of TSH in the first trimester. A TSH level between 4.0 and 10.0 mIU/L, combined with free thyroxine (T4) within the normal range, is defined as subclinical hypothyroidism, and a TSH level over 10 mIU/L is defined as overt hypothyroidism regardless of the free T4 level. Levothyroxine treatment is recommended when the TSH level is higher than 4 mIU/L in subclinical hypothyroidism, regardless of thyroid peroxidase antibody positivity. However, thyroid hormone therapy to prevent miscarriage is not recommended in thyroid autoantibody-positive women with normal thyroid function.

The incidental detection of thyroid nodules by ultrasound (US) is increasing explosively. The clinical significance of these nodules is that 5% to 15% of them are malignant, requiring adequate treatment including surgery. Clinical guidelines for the management of thyroid nodules has been published and revised by many thyroid associations around the world in the past decade. The Korean Endocrine Society has also published guidelines for the management of thyroid nodules and thyroid cancer, and the Korean Thyroid Association has recently revised these guidelines. The revised guidelines include the size criteria for which fine needle aspiration cytology (FNAC) is warranted and the Bethesda system, a new cytologic diagnosis system in which thyroid nodules are classified by the degree of malignancy potential. US is recommended to evaluate thyroid nodules in detail. FNAC should be performed for the suspicious cervical lymph nodes regardless of their size and for thyroid nodules larger than 0.5 cm in patients with clinically high risk history and sonographically suspicious findings. Otherwise, FNAC is indicated for thyroid nodules larger than 1 cm in diameter. Repeated FNAC is indicated for nodules with cytologic diagnosis of 'nondiagnostic' or 'atypical cell of unknown significance'. Surgery is needed for nodules diagnosed as 'follicular neoplasm (Hurthle cell type)', 'suspcious for malignancy' and 'malignancy'. For 'benign' nodules, only follow-up with US+/-FNAC is needed. Well-designed studies on thyroid nodules in Korean patients would provide evidence for Korean guidelines for thyroid nodules. Conclusion: The revised Korean Thyroid Association guidelines for thyroid nodules are very useful for managing patients.
Biopsy, Fine-Needle ; Follow-Up Studies ; Humans ; Lymph Nodes ; Thyroid Gland ; Thyroid Neoplasms ; Thyroid Nodule

No abstract available.
Thyroid Gland ; Thyroid Nodule

No abstract available.
Graves Disease* ; Hypothyroidism*

Correction of the text.

As the detection of thyroid nodules increases, it is important to differentiate whether thyroid nodules are malignant or not. Ultrasonography-guided fine-needle aspiration cytology is the standard method to diagnose thyroid nodules. Ultrasonographic findings of thyroid nodules can predict the risk of malignancy, and fine-needle aspiration allows the examination of cytopathology of thyroid nodules. However, both are not perfect, with a certain degree of false negative or false positive results. Therefore, we can face thyroid nodules with discordant results of ultrasonographic and fine-needle aspiration findings. In the case of benign features on ultrasonography with malignant cytology, follicular thyroid cancer, follicular variant papillary thyroid cancer, cystic or degenerative changes of thyroid cancer, and thyroiditis are candidates for diagnosis. In contrast, for the nodules with ultrasonographic features of highly suspicious of malignancy but benign cytology, we can consider the possibility of thyroiditis, changes of benign nodule, and cystic changes of thyroid cancer. These various conditions may result in discordant results of ultrasonographic features and fine-needle aspiration cytology, which need special attention not to miss the diagnosis of malignant nodules.
Biopsy, Fine-Needle ; Diagnosis ; Methods ; Thyroid Gland ; Thyroid Neoplasms ; Thyroid Nodule ; Thyroiditis ; Ultrasonography