Fine Needle Aspiration
	We prefer fine needle aspiration with cytological examination over thyroid biopsy, because diagnostic accuracy of the two methods is about equal and the former is less traumatic and causes less side effects, such as bleeding complications or potential translocation of malignant cells than the latter. We recommend puncture after local desinfection without anaesthesia with the use of a canule 0.6 to 0,7 mm in diameter. For smaller nodules, the correct targeting of the needle must be supervised by ultrasonography. Indications for fine needle aspiration generally include: Any nodule exceeding 1.0 cm in size, except for scintigraphically documented autonomously functioning nodules which are known to rarely harbor carcinoma. Smaller lesions may in most cases be sufficient to be followed up by ultrasonography after 3-6 months, thereafter at yearly intervals. In that case the delay in diagnosis of a differentiated thyroid microcarcinoma would not adversely affect the prognosis of the patient. Rapidly growing focal lesions. Suspicion of an intrathyroidal metastasis of a non-thyroidal tumor. Purulent thyroiditis Subacute thyroiditis de Quervain if diagnosis is ambiguous Chronic autoimmune thyroiditis in case of a suspicion of lymphoma Aspiration of cysts. Sensitivity and specificity of cytology has been reported to be approximately 90 and 95 % respectively, three prerequisites being attainment of an appropriate sample, interpretation by an experienced cytologist and correlation to clinical features. While papillary carcinoma may cytologically be readily recognizable, follicular carcinoma may hardly be distinguished from follicular adenoma, except by demonstration of capsular or vascular invasion but not by cytomorphological criteria. For that reason, the term follicular neoplasia has been coined to comprise benign or malignant follicular tumors. Cytological finding of follicular neoplasia requires surgery, preferably hemithyroidectomy, and careful examination of histological sections.