Localization of the Sentinel Lymph Node in Melanoma Without Blue Dye

The purpose of this study was to assess regional recurrence rates of patients who underwent sentinel lymph node biopsy (SLNB) using radiocolloid guidance alone.

Isosulfan blue dye is commonly used along with Tc99-labeled radiocolloid localization in SLNB for melanoma. Blue dye has, however, been associated with allergic reactions, long-term staining of skin, and increased cost. We hypothesized that the rate of regional recurrence when SLNB is performed with radiocolloid alone would be comparable to established reports using both radiocolloid and blue dye.

A prospectively collected database was retrospectively queried for patients who underwent SLNB for melanoma during the years 2005 through 2008. Data collected included patient demographics, primary lesion characteristics, operative details, and recurrence. The primary outcome was the rate of recurrence within the biopsied basin after negative SLNB's performed without isosulfan blue dye.

In 215 patients, 279 nodal basins were identified. All patients underwent successful radiocolloid localization, and positive sentinel nodes were found in 40 patients (18.6%). Six of 175 patients with a negative SLNB developed a regional node recurrence as the first site of metastasis (3.4%). Among all 215 patients, 44 experienced recurrence of any kind (20.5%). Higher mitotic rate and Breslow depth were significantly associated with likelihood of recurrence.

Success rates, node positivity rates, and rates of regional recurrence after SLNB for melanoma using radiocolloid alone are acceptable and similar to those of prior reports using blue dye plus radiocolloid.