LACK OF EFFECT OF PARTICLE-SIZE ON THE IDENTIFICATION OF THE SENTINELNODE IN CUTANEOUS MALIGNANCIES

Background: Radiotracers have become a routine technical component of the new procedure of intraoperative lymphatic mapping and selective ly mphadenectomy. Because different colloids have differing physicochemic al properties, their distribution and uptake may be different. For thi s reason, the optimal colloid to identify and localize the sentinel no de remains controversial. Methods: Nineteen consecutive patients with cutaneous malignancies underwent diagnostic lymphoscintigraphy with Tc -99m-labeled human serum albumin (Tc-99m-HSA) and preoperative lymphos cintigraphy with Tc-99m-labeled sulfur colloid (Tc-99m-SC). The result s of intraoperative lymphatic mapping and selective lymphadenectomy we re reviewed. Results: Intraoperative lymphatic mapping and selective n ode dissection were successful in 21 of 22 lymphatic basins (18 of 19 patients). There was excellent correlation between the ''hot'' marker placed on the skin surface when Tc-99m-HSA was used compared with the use of Tc-99m-SC. In 20 of 21 lymphatic basins the sentinel node both was ''hot'' and was stained with isosulfan blue. Conclusions: No disce rnible difference between the ability to localize in the sentinel node with these two radiocolloids was identified. For logistical reasons, (TC)-T-99m-SC appears to be the colloid of choice in intraoperative ly mphatic mapping.