['The purpose of this study was to determine the specific sonographic features of primary thyroid lymphoma and its color Doppler pattern compared to nodular goiter.', 'The sonographic findings for 13 surgically proven primary thyroid lymphomas were analyzed and compared to those for 27 nodular goiters.', 'In accordance with the suggested pathologic patterns, the sonographic patterns of primary thyroid lymphoma could be classified into diffuse and nodular or segmental types based on the distribution of hypoechoic and echogenic structures within the lesions. Some common sonographic characteristics suggesting thyroid malignancy could not facilitate differentiation of primary thyroid lymphoma from nodular goiter. However, a central blood flow pattern would favor the diagnosis of primary thyroid lymphoma, whereas a peripheral pattern would suggest the diagnosis of nodular goiter.'] Does primary thyroid lymphoma have different sonographic and color Doppler features compared to nodular goiter?