THYROID-CANCER ASSOCIATED WITH ADENOMATOUS GOITER - AN ANALYSIS OF THE INCIDENCE AND CLINICAL FACTORS

We evaluated the incidence of thyroid cancer in patients with adenomat ous goiter and investigated the clinical factors distinguishing patien ts with occult thyroid cancer, defined as a tumor size smaller than or equal to 10mm, from those with clinical thyroid cancer, defined as a tumor size larger than 10mm. Of 835 patients with histologically confi rmed adenomatous goiter, 256 (30.7%) also had thyroid cancer, being oc cult in 137 patients and clinical in 119 patients. There was no correl ation between the maximum size of the thyroid cancer tumor and the age of the patient, and the percentage of patients with thyroid cancer in each group was not influenced by age. There were no significant diffe rences in age, sex, the serum concentrations of free triiodothyronine, free thyroxine, thyrotropin, and thyroglobulin, or the urinary iodine creatinine ratio, The frequency of calcified lesions being detected b y ultrasonography (US) and/or neck X-ray in the patients,vith clinical thyroid cancer was significantly greater than that in those with occu lt cancer at 83% vs 57%, respectively (P < 0.0001). This study disclos ed a high prevalence of thyroid cancer associated with adenomatous goi ter, and the results suggest that a considerable number of associated carcinomas remain occult. The detection of calcification in the thyroi d gland is one of the surgical indications for patients,vith adenomato us goiter.