Sentinel Lymph Node Detection in Patients with Oral Cancer by MR Lymphography using Superparamagnetic Iron Oxide

The purpose of this study was to examine the feasibility of interstitial MR lymphography using Superparamagnetic Iron Oxide (SPIO) to detect sentinel lymph nodes (SLNs) in head and neck cancer. For two patients with cT2N0 squamous cell carcinoma of the tongue, the submucosal injection of SPIO as well as sentinel lymph node navigation surgery (SLNNS) was performed before undergoing surgical treatment. SPIO was used for MR lymphography and Tc-99m phytate for SPECT. We compared the images by both modalities. Berlin blue stain was also performed postoperatively to verify if SLNs had the uptake of SPIO. The lymph nodes with MR signal attenuation and those with hot spots were probed to be anatomically identical. All the lymph nodes detected as a SLN by a gamma-probe contained the blue granules from SPIO. These data suggest that SPIO can be a novel tracer for performing SLNNS and SLN biopsy (SLNB) in oral cancer patients with cN0 neck.