[Frequency of carcinoma in thyroid cysts]

The view that cystic thyroid nodes are as a rule benign is disproved by reports from the recent literature which quote an incidence of 17-32% of malignancies in conjunction with thyroid cysts. In 66 patients, investigated by the authors, with thyroid lesions confirmed on biopsy four suffered from thyroid carcinoma (two follicular, one papillary and one solid to anaplastic), i.e. a malignancy in 6%. In the literature it is recommended to follow up on a long-term basis patients with cysts which after thin-needle biopsy do not recede adequately or refill. Biopsies must be repeated, as the cytological yield of biopsies in these instances is not as reliable as in solid nodes. A haemorrhagic appearance of the bioptic specimen and anamnestic data on previous irradiation in the head or neck area are also considered risk factors.