[Thyroid nodules: assay of serum thyrotropin and cytopuncture versus scintigraphy as first-line tests. Prospective study with 150 cases].

Objective: Fine-needle aspiration (FNA) is now considered as the first-line investigation for the diagnosis of thyroid nodules. We searched for a more accurate and cost-effective methodology as this technique fails to recognized hot nodules, frequent in certain countries.

Patients And Methods: A prospective study was conducted in 150 patients to compare two diagnostic procedures: scintigraphy first combined with FNA in case of cold nodules versus TSH measurement plus FNA when TSH measurement plus FNA when TSH was not depressed. The results were subjected to cost/benefit analysis.

Results: Cystic nodules were found in 28 cases (including 3 hyperfunctionning nodules, with 5 suspicious smears (1 carcinoma). FNA was non-diagnostic in 26 patients; 12 were operated on (1 carcinoma), 14 had further FNA (5 suspicious, 9 benign). Altogether 56 nodules were removed, for toxic adenoma (n = 5), for suspicious (n = 21) or malignant (n = 12) smear, or on personal (n = 18) demand; 16 carcinomas were found (2 medullary, 13 capillary, 1 follicular carcinomas). With scintigraphy first, the cost was 787 French francs (FF) per patient. With TSH measurement and FNA, the cost was 554 FF per patient. In both cases, the same number of carcinomas were removed, and all the hot nodules (11 including 5 toxic adenomas) were detected.

Conclusion: Serum TSH measurement, with scintigraphy if TSH is low, and FNA in all the other cases, is accurate and more cost-effective than scintigraphy as a first-line investigation for the diagnosis of thyroid nodule.