Surgery for Solitary Thyroid Nodules: Assessment of Methods to Select Patients at Low Risk for Unsuspected Malignancy in the Unaffected Lobe and the Possible Utility of Preoperative Thyroid Ultrasound3

One hundred and twelve bilateral thyroidectomies for solitary thyroid nodules with suspected malignancy were performed. The incidence of malignancy in the 112 primary nodules was 42%. Twenty-nine of the 112 contralateral lobes (26%) contained malignancy, which was unsuspected in 80%. Of these 29, 20 were foci of papillary cancer ≤5 mm and 9 were larger papillary tumors or follicular carcinoma. We analyzed these 112 patients to determine whether there was a simple method to identify those patients at risk for contralateral, unsuspected malignancy. With use of the AMES clinical staging retrospectively, 70 of the 112 patients were classified as having low-stage disease. Fifty percent (35) had cancers on the primary side and 27% (19) on the contralateral side. Of these 19 contralateral cancers, 14 were papillary cancers ≤5 mm, 4 were papillary cancer >5 mm and one was a 1.5 cm follicular carcinoma, a similar distribution as in the whole group of 112. When the AMES analysis then excluded those thought to be at...