SOLITARY THYROID-NODULE - COMPARISON BETWEEN PALPATION AND ULTRASONOGRAPHY

Objective: To determine the accuracy of clinical palpation in the diag nosis of solitary thyroid nodule in comparison with ultrasonographic f indings. Methods: From a computerized database of 1774 patients with t he diagnosis of nodular thyroid disease made from January 1990 through December 1991 at our institution, we retrieved and reviewed the medic al records of the 193 patients 'who underwent ultrasonography of the t hyroid (42 patients with multinodular glands on palpation were exclude d). Nodules were categorized as ''solitary'' or ''dominant nodule of a multinodular gland.'' Concordance rates were measured between results of palpation and ultrasonographic findings. Results: Of 151 patients included in the study, 78 had solitary nodules on ultrasonography and 73 had multiple nodules. Of those with multiple nodules, 49 had two no dules and 24 had three or more nodules. Of clinically palpable nodules , 89% were 1 cm or greater in diameter, In 72% of the patients with mu ltiple nodules, the other nodules not identified on palpation were les s than 1 cm in diameter, The overall concordance rate between the size of the solitary nodule or the dominant nodule in a multinodular gland estimated with clinical palpation and the actual size seen on ultraso nography was 72%. The relationship between multiple nodules and malign ancy was not statistically significant. Conclusions: Our results sugge st that (1) a palpable solitary nodule represents a multinodular gland in about 50% of patients, (2) clinical palpation is less sensitive th an thyroid ultrasonography in identifying multiple nodules, and (3) pa lpation is reliable only if a nodule is at least 1 cm in diameter. We recommend that small, occult (impalpable) thyroid nodules not be consi dered clinically important; they do not warrant further evaluation unl ess ultrasonographic features suggest malignancy or the nodule increas es in size.