Visualization of lymphatic basin from the tumor using magnetic resonance lymphography with superparamagnetic iron oxide in patients with thoracic esophageal cancer

Objective: To evaluate magnetic resonance (MR) lymphography with submucosal injection of superparamagnetic iron oxide (SPIO) for imaging lymphatic pathways from thoracic esophageal cancer. Methods: In 24 patients with esophageal cancer, SPIO was injected into the submucosal layer of the peritumoral region endoscopically and MR lymphography was conducted. In study 1, fast spoiled gradient-recalled acquisition using a steady-state (FSPGR) sequence was performed from the neck to the upper abdomen before and at 20, 40, and 60 minutes after injection in 10 patients. In study 2, FSPGR and spin echo T1-weighted images were obtained after injection in 14 patients. Areas scanned were the neck to the upper mediastinum and the upper abdomen. Results: In study 1, at 20 minutes after injection, the signal of each lymph node appeared attenuated when compared with precontrast images. The signal-to-noise ratio in lymph nodes exhibiting influx of SPIO was significantly lower than that found on precontrast images (P < 0.0005). In study 2, influx to the neck lymph nodes was detected in 8 patients (64.3%), whereas influx to the upper abdominal lymph nodes was detected in 13 (92.9%). Conclusions: Magnetic resonance lymphography with SPIO Could visualize the lymphatic pathways draining from the injection site and the location of lymph nodes exhibiting influx of SPIO in patients with thoracic esophageal cancer.