[A nodule in the thyroid gland. Preoperative examinations and treatment--an analysis of 990 cases]

It is very difficult to know whether a nodule in the thyroid gland is benign or malignant as judged by a clinical examination, scintigraphy, US, or FNA.

Over a 10-year period a series of 1509 patients were operated on for diseases in the thyroid gland. The indication for surgical intervention in 990 patients was a nodule in the thyroid gland, defined as a solitary nodule or a suspicious nodule in a goitre.

The incidence of malignancy in these 990 patients with a nodule was 6.3% with no difference between men and women. Forty-four per cent were follicular adenomas and the rest were colloid nodules. No increased incidence of malignancy in nodules was found with increasing size, whereas the incidence significantly increased with advancing age. Scintigraphy was carried out in almost all the patients (98.9%). Seventy-five per cent had a cold nodule, 9% irregular uptake, and 17% a warm nodule. Only one malignancy, a follicular carcinoma, was a warm nodule. FNA was performed in 955 of the 990 patients (97%). The incidence of follicular neoplasia was 33% in the benign nodule and 70% in the follicular adenoma.

When malignant cells were found by FNA, it was an almost certain sign of malignancy with very few false positive results, whereas a follicular adenoma or a malignant tumour cannot be excluded by a negative answer. The risk of complications was very low, with an 0.3% incidence of recurrent nerve palsy. If and when the risk can be kept at a reasonably low level, the advantages of thyroid surgery will out-number the disadvantages and early surgery is therefore preferable.