Lymph node metastases in patients with cutaneous melanoma: improvements in diagnosis by signal-enhanced color Doppler sonography.

Abstract

The purpose of the study was to evaluate whether signal-enhanced color Doppler sonography (CDS) is superior to native CDS in detection of characteristic vascularity patterns that are important for the differentiation between benign and malignant lymphadenopathy in patients with cutaneous melanomas. Twenty-two melanoma patients presenting with 24 structures suspicious for metastases in B-Mode sonography were examined using native and signal-enhanced CDS in a prospective two-center study. Presumptive sonographic diagnoses were compared with results of histopathological and follow-up examinations. Signal-enhanced CDS gave additional information about vascularization of lymph node metastases and reactive lymph nodes, which was indicative for the differential diagnosis in 12 of 24 examinations. For lymph node metastases, signal enhancement improved the visualization of accessory peripheral vessels in four of 10 examinations. Concerning reactive lymph nodes, hilar vessels in part with branching to the lymph node periphery could be better identified after application of the contrast enhancer in eight of 13 examinations. Signal-enhanced CDS is demonstrated as an important additional diagnostic tool for improved differentiation between malignant and reactive lymph nodes and may be of special value in preventing unnecessary lymphadenectomy in small reactive lymph nodes.