Hürthle cell neoplasms (HNC) of the thyroid gland are uncommon, but potentially malignant lesions. Opinion is divided as to their most suitable surgical treatment. In the ten-year period between 1976 and 1986, 46 patients with Hürthle cell tumor underwent surgery in our Department. Preoperative diagnosis was made by fine needle biopsy. In all cases but six, total lobectomy plus isthmusectomy was performed. In our experience HCC can be differentiated from benign forms by careful evaluation of invasive malignancy criteria performed by an experienced thyroid pathologist and by electron microscopy. In agreement with Bondeson et al. we found that lesions larger than 2 cm should not be considered potentially malignant, and do not warrant aggressive surgical treatment. Therefore, on the basis of our experience, we initially treat Hürthle cell tumors with hemithyroidectomy and isthmusectomy, and only if biopsy tissue shows histologic and electron microscopic signs of malignancy, do we resort to total thyroidectomy.