SMALL THYROID-NODULES AND MICROCANCERS

Thyroid nodules less than one centimetre in diameter raise the problem of differential diagnosis between a benign formation and cancer. The question is of major importance since nodules can be found in approxim ately one-half of the population. Fine-Needle Aspiration should be per formed if the nodule is palpable. When cytologic diagnosis is not poss ible, the discovery of a small nodule in the thyroid gland is not an a larming finding in itself as long as the absence of involvement of the satellite nodes or other associated symptomatology is confirmed. We h ave operated 102 patients with differentiated microcancers with no met astasis other than local node involvement. All have been seen regularl y for annual check-ups and only 2 have developed pulmonary and bone me tastases with a fatal outcome. The prognosis of microcancers is thus m uch better than that of larger tumours since in a series of more than 500 cancers we have observed 5 and 10 year survivals of 96 and 92% res pectively. In addition, unlike large tumours, small cancers of the thy roid are not anaplasic. We thus propose annual surveillance for patien ts with uncomplicated small nodules of the thyroid gland less than 2 c m in diameter. Complementary examinations should be limited. Conversel y we operate the nodules exceeding 2 cm in order to reduce the frequen cy and severity of thyroid cancer. It should be recalled that neither clinical manifestations, echography, thyroglobulin, needle biopsy, nor any other diagnostic tool has been shown to have sufficient prognosti c power to predict the benign nature of a voluminous nodule.