[Which thyroid nodules need to be operated? (author's transl)].

Up to 20% of isolated cold thyroid nodules are malignant neoplasms. However, in the case of 1-4 cm large nodules entirely cystic as demonstrated by echotomography, surgery is not necessary as the frequency of malignancy is only 1%. In cases of hot nodules the risk of cancer is regarded as almost nil, but such nodules can lead to thyrotoxicosis. Treatment by surgery or 131l will depend on the patient's age and condition; it must be performed for all hyperthyroid patients and, as a preventive measure, for all elderly or cardiac patients to prevent the consequences of even slight hyperthyroidism. The complete work up of a nodule requires not only scintigraphy and thyroid echotomography but also a careful clinical examination, tracheal X-ray, determination of serum antithyroid antibodies, assessment of thyroid function and, in some cases, trial therapy using thyroid hormones.