The single palpable thyroid nodule: evaluation by 99mTc-pertechnetate imaging.

The role of 99mTc-pertechnetate thyroid imaging in the preoperative assessment of patients with single palpable thyroid nodules was evaluated. The frequency of cancer in hypofunctional nodules was similar to that found in previous studies with 131I. The 99mTc-pertechnetate image allowed a reliable separation of pathologically uninodular thyroids from those that were multinodular, and demonstrated multiple thyroid lesions that had not been detected by physical examination in over one-third of the cases. The frequency of cancer in thyroids containing a solitary or dominant hypofunctional nodule was higher (17%) than that in thyroids with a multinodular scan appearance (less than 5%).