A total of 130 superficial lymph nodes were evaluated using color Doppler flow imaging (CDFI) in order to differentiate benign from malignant lymphadenopathy. The patterns of intranodal flow signals detected at standardized conditions by CDFI were classified using eight self-defined criteria and were correlated with the histopathological or clinical diagnosis. Nonparametric discriminant analysis showed that four vascular were suspicious of malignancy: (a) avascular areas, (b) displacement of intranodal vessels, (c) accessory peripheral vessels and (d) aberrant course of central vessels. Of the neoplastic lymph nodes (n = 73), 96% showed at least one pathological vascular pattern. Malignancy could be excluded in 95% of 57 reactive lymph nodes using these four criteria. Most reactive lymph nodes in contrast demonstrated a vascular hilus and/or vessels running at the long axis of the lymph node with branches to the cortex. There was a diagnostic accuracy of 41-82% in the additionally evaluated sonomorphological (size, shape, echogenicity) and Doppler (increased Pourcelot's or pulsatility indices) criteria. The definitive interpretation of the promising results of this retrospective study requires confirmation of examiner independency as well as a prospective evaluation.