First experiences with a new radiopharmaceutical for sentinel lymph node detection in malignant melanoma: (99m)Tc colloidal rhenium sulphide

Abstract

AIM of this study was to localize the sentinel lymph node by lymphoscintigraphy using technetium-99m colloidal rhenium sulphide (Nanocis), a new commercially available radiopharmaceutical. Due to the manufacturers' instructions it is licensed for lymphoscintigraphy. 35 consecutive patients with histologically proved malignant melanoma, but without clinical evidence of metastases, were preoperatively examined by injecting 20-40 MBq Nanocis with (mean particle size: 100 nm; range: 50-200 nm) intradermally around the lesion. Additionally blue dye was injected intraoperatively. A hand-held gamma probe guided sentinel node biopsy. During surgery, the preoperatively scintigraphically detected sentinel lymph nodes were identified in 34/35 (97%) patients. The number of sentinel nodes per patient ranged from one to four (mean: n = 1.8). Histologically, metastatic involvement of the sentinel lymph node was found in 12/35 (34%) patients; the sentinel lymph node positive-rate (14/63 SLN) was 22%. Thus, it is comparable to the findings of SLN-mapping using other technetium-99m-labeled nanocolloides. (99m)Tc-bound colloidal rhenium sulphide is also suitable for sentinel node mapping.