Unifocal autonomous thyroid nodule and carcinoma

Two cases operated upon with the clinical diagnosis of unifocal autonomous functioning thyroid nodules (AFTN) are reported where the histological diag nosis revealed a well differentiated thyroid carcinoma (follicular, papilla ry) without metastasis. The pathogenesis of differentiated thyroid carcinom as in cases of AFTN may be coincident. Alternatively it may evolve from thy roid epithelial cells of the hot nodule, resulting in a "hot" well differen tiated thyroid carcinoma. These cases show that under the clinical diagnosi s of AFTN a differentiated thyroid carcinoma can be hidden occasionally.