Patients with primary cutaneous
melanoma underwent sentinel node (SN) mapping and biopsy at 25 facilities in Japan by the combination of radiocolloid with gamma probe and
dye. Technetium-99m ((99m)Tc)-tin
colloid, (99m)Tc-phytate, 2%
patent blue violet (PBV) and 0.4%
indigo carmine were used as tracers. In some hospitals, 0.5% fluorescent
indocyanine green, which allows visualization of the SN with an infrared camera, was concomitantly used and examined. A total of 673 patients were enrolled, and 562 cases were eligible. The detection rates of SN were 95.5% (147/154) with the combination of
tin colloid and PBV, 98.9% (368/372) with the combination of
phytate and PBV, and 97.2% (35/36) with the combination of
tin colloid or
phytate and
indigo carmine. SN was not detected in 12 cases by the combination method, and the primary
tumor was in the head and neck in six of those 12 cases. In eight of 526 cases (1.5%), SN was detected by PBV but not by radiocolloid. There were 13 cases (2.5%) in which SN was detected by radiocolloid but not by PBV. In 18 of 36 cases (50%), SN was detected by radiocolloid but not by
indigo carmine. Concomitantly used fluorescent
indocyanine green detected SN in all of 67 cases. Interference with transcutaneous oximetry by PVB was observed in some cases, although it caused no clinical trouble.
Allergic reactions were not reported with any of the tracers. (99m)Tc-tin
colloid, (99m)Tc-phytate, PBV and
indocyanine green are useful tracers for SN mapping.