Sentinel node detection in breast cancer using contrast‐enhanced sonography with 25% albumin—Initial clinical experience

Purpose. To determine the clinical usefulness of a sentinel lymph node (SLN) identification technique using contrast‐enhanced sonography (CEUS) with 25% albumin. Methods. The subjects were 23 women with breast cancer. Each was injected subcutaneously with 5 ml of 25% albumin solution as a negative contrast agent directly superficial to the breast tumor. The area was massaged, and the inferior axillary hairline was examined continuously using gray‐scale sonography with a 7.5‐ or 10‐MHz transducer. Any contrast‐enhanced lymph node was considered a CEUS‐detected SLN, was differentiated from other level I and II nodes, and was resected and pathologically assessed. Results. In all 23 patients, 1 or 2 CEUS‐detected SLNs (mean, 1.3 SLNs) were identified. Their sizes ranged from 5 mm to 25 mm (mean, 11.3 mm), and their depths (from the skin surface) ranged from 5mm to 20 mm (mean, 12.6 mm). Pathologic examination revealed a metastasis in 5 of the 23 patients, all in CEUS‐detected SLNs. Conclusions. In a clinical study using CEUS with 25% albumin, contrast‐enhanced nodes were identified in all subjects. The pathologic findings suggested that any metastatic nodes observed were SLNs, indicating that this technique may represent a new modality for SLN identification. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:317–326, 2006