Sentinel lymph node detection using laser-assisted indocyanine green dye lymphangiography in melanoma and breast cancer patients.

Abstract

8587 Background: Sentinel lymph node (SLN) biopsy is a vital component of staging and management of multiple cancers. The current gold standard utilizes technetium 99 and methylene blue (MB) to detect regional nodes. These two methods can be inconclusive or inconvenient for both patient and surgeon. We evaluated a new technique using laser-assisted ICG dye lymphangiography to identify SLN. Methods: In this retrospective analysis, we identified patients with melanoma or breast cancer who required SLN biopsy. Patients received an injection of technetium 99 the day prior to surgery, then 1-2 mL of MB and 0.9 mL of ICG (2.25mg) in the operating room. After 10 minutes the ICG device (Novadaq SPY) was used to detect real time lymphatic flow towards the SLN bed. Any nodes that were denoted as hot by gamma probe, blue by direct visualization, intense for ICG, or any combination of the three, were removed and evaluated as SLNs. Results: A total of 16 patients were evaluated, with 9 females and 7 males having a median age of 61 (40-87). One patient had breast cancer, the remaining 15 melanoma. The number of SLNs ranged from one to six per patient. In total, 42 SLNs were removed, with final staging between stage IB to IIIB. An equivalent amount 90% (38/42) SLNs were identified using either ICG or a combination of tech 99 and MB. When analyzed individually, tech 99 found 74% (31/42) of the nodes, MB 45% (19/42) and ICG 90% (38/42). Four patients were found to have metastatic disease on final pathology. 100% of these 4 nodes were identified using ICG, while only 75% (3/4) were positive for tech 99 and/or MB. Furthermore, none of the nodes missed by ICG (4/42) had malignant cells. Conclusions: ICG dye lymphangiography is a reasonable alternative for locating SLNs in patients with melanoma and breast cancer. This technique could potentially eliminate MB, technetium 99 or both and result in reduced hospital trips, removal of radioactive material and decreased tissue staining. Prospective studies are needed to better ascertain the full functionality of this technique.