The relationship of thyroid tissue weight and volume to malignancy in nodular goiter patients is not clear. The general belief is that heavier and larger tissues are related to malignancy. Total thyroidectomy was performed in 52 nodular goiter patients (41 females and 11 males; age range 20-78 years; mean age 47.8 years) with suspected malignancy. Resected fresh tissues were weighed with a precision scale, and computed tomography (CT) images were acquired immediately thereafter for volumetric evaluation. Thirty cases (57%) were benign, and 22 (43%) cases were malign. The average weights of benign and malign thyroid tissues were 92.38 +/- 71.09 g and 52.40 +/- 49.75 g, respectively (p = 0.02). The average volumes of the benign and malign tissues were 19.8 cm(3)and 12.1 cm(3), respectively (p = 0.02). Cases of malign thyroid tissues are lighter and smaller than those of benign cases.