Thyroid nodule of 4 cm size, mobile but causing compressive symptoms, all are true EXCEPT:

Cold nodules are diagnostic of malignancy REF: Bailey and love 25th ed page 779 Discrete thyroid swellings (thyroid nodules) are common and are present in 3-4% of the adult population in the UK and USA. They are three to four times more frequent in women than men. The impoance of discrete swellings lies in the increased risk of neoplasia compared with other thyroid swellings. Some 15% of isolated swellings prove to be malignant, and an additional 3040% are follicular adenomas. The remainders are non-neoplastic. Isotope scan Isotope scanning used to be the mainstay of investigation of discrete thyroid swellings to determine the functional activity relative to the surrounding gland according to isotope uptake. On scanning, swellings are categorised as 'hot' (overactive), 'warm' (active) or 'cold' (underactive). About 80% of discrete swellings are cold. The risk of malignancy is higher in "cold" lesions (20%) compared to "hot" or "warm" lesions (<5%). FNAC is the investigation of choice in discrete thyroid swellings. But it is unable to distinguish between follicular adenoma from carcinoma. Treatment Approximately 50% of these nodules decrease in size in response to the TSH suppression, and others may not continue to grow, but it is most effective for nodules <3 cm The main indication for operation is the risk of neoplasia. Thyroidectomy should be performed if a nodule enlarges on TSH suppression, causes compressive symptoms, or for cosmetic reasons reasons