Intraoperative Sentinel Lymph Node Mapping Using a New Sterilizable Magnetometer in Patients with Nonsmall Cell Lung Cancer

Purpose We recently developed a novel method for sentinel lymph node mapping using magnetic force. However, problems with the sterility and sensitivity of the magnetometer made intraoperative sentinel lymph node mapping impossible. The purpose of this study was to test the utility of a new, more sensitive, sterilizable magnetometer developed in our institute for in vivo sentinel lymph node mapping in patients with nonsmall cell lung cancer. Description Ferumoxides (magnetite) served as the tracer. Twenty patients with nonsmall cell lung cancer participated in the study. Each received 5 mL of ferumoxides, which were injected around their tumor. Magnetic force was then measured intraoperatively using the new sterilizable magnetometer. Evaluation The in vivo sentinel lymph node detection rate was 80.0% (16 of 20). The accuracy, sensitivity, and false-negative rates were 100% (16 of 16), 100% (4 of 4) and 0% (0 of 12), respectively. Our preliminary study indicates that our new magnetometer enables in vivo sentinel lymph node mapping in patients with nonsmall cell lung cancer. Conclusions This device safely and accurately detected sentinel lymph nodes in nonsmall cell lung cancer patients.