الفهرس 
Thyroid AnatomyOnly 14 pages are availabe for public view
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Abstract
Thyroid nodules are very common: They are found in 4%–8% of adults by means of palpation,
The overall incidence of cancer in patients with thyroid nodules selected for FNA is approximately 9.2%–13.0%, no matter how many nodules are present at US
The majority (75%–80%) of new cases of thyroid cancer diagnosed will be papillary thyroid cancer.
The morbidity and mortality rates of thyroid cancer are low compared with the rates for many other cancers
A thyroid nodule is a discrete lesion within the thyroid gland that is sonographically distinguishable from the adjacent parenchyma. For each thyroid nodule, gray-scale and color Doppler US are used to evaluate the US features, which include size, echogenicity (hypoechoic or hyperechoic), and composition (cystic, solid, or mixed), as well as presence or absence of coarse or fine calcifications, a halo, irregular margins, and internal blood flow. Many studies have been published in which the ability to predict whether a thyroid nodule is benign or malignant on the basis of US findings was assessed
Colour Doppler US has also been evaluated as a diagnostic tool for predicting thyroid cancer, with the hypothesis that flow that is predominantly at the periphery of a nodule is suggestive of a benign nodule, while flow predominantly in the central portion of the nodule is suggestive of malignancy.
Isotope scan is also used to evaluate the nature of nodule and categorized it’s according to its behaviour to hot, warm and cold
FNA with cytological evaluation has become the accepted method for screening a thyroid nodule for cancer, and, in the hands of an experienced cytologist, FNA has a high accuracy rate.
Patients with thyroid cancer are usually treated with a total thyroidectomy. This enables subsequent follow-up with 131I-scintigraphy and serum thyroglobulin measurement. Subtotal operations are followed by 131I-ablation therapy. Clinical evaluation, repeat scintigraphy and serum thyroglobulin measurement are performed 6–12 months later to assess the adequacy of ablation and to detect and treat metastatic disease under elevated TSH drive. Whole-body iodine imaging is performed after discontinuing thyroid hormone (for 4 weeks for T4 or for 2 weeks for T3) and establishing that TSH concentrations are >30 μmol L-1, It is also possible to image these patients without discontinuing thyroid medication using recombinant TSH, although slightly better results are achieved by suspending conventional thyroid medication.131I-whole-body imaging can identify most functioning metastases, which are usually in the neck, lungs, or bone
Other modality are used in management of solitary thyroid nodule as percutanous ethanol injection and radio frequency