SONOGRAPHIC APPEARANCES OF SMALL HEPATIC NODULES WITHOUT TUMOR STAIN ON CONTRAST-ENHANCED COMPUTED-TOMOGRAPHY AND ANGIOGRAPHY

Purpose. We report the sonographic appearances and pathologic findings for hepatic nodules 2 cm or smaller that were detected by sonography but that did not produce a tumor stain on constrast-enhanced helical C T or digital subtraction angiography. Methods. Sixty-six nodules 2 cm or less were found by sonography in 39 patients. Sonographically guide d needle biopsies were done an all lesions. Results. Twenty-seven nodu les were benign nodules, 9 were borderline lesions, and 30 were hepato cellular carcinomas. Benign nodules were significantly smaller than he patocellular carcinomas (mean size, 1.0 cm versus 1.4 cm, respectively ; p < 0.00001). Nodules 1 cm or smaller were more likely to be diagnos ed as benign nodules (68%) than as either of the other types (32%; p = 0.01). A significantly greater percentage of hepatocellular carcinoma s showed a heterogeneous pattern (64%) on sonography compared with ben ign nodules (25%) and borderline lesions (11%; p = 0.04). In nodules 1 cm or smaller, a homogeneous pattern (68%) was more common than a het erogeneous pattern (32%; p = 0.01). Conclusions. The nature of small h epatic nodules cannot be determined with sonography. Thus, biopsy rema ins the only technique for obtaining a definitive diagnosis. (C) 1998 John Wiley & Sons, Inc.