Inferior epigastric artery lymph nodes: A pathway for systemic dissemination from peritoneal carcinomatosis?

Background and Objectives We report, for the first time in the literature, a metastatic lymphatic pathway along the inferior epigastric vessels, through the inferior epigastric lymph nodes (IELNs), in patients with peritoneal carcinomatosis (PC). Interestingly, these lymph nodes (LNs) in the anterior retroperitoneum were not detectable on preoperative imaging. They may, however, represent a pertinent systemic dissemination pathway for PC. Patients and Methods In patients undergoing indocyanine green-fluorescence imaging during cytoreductive surgery for PC, an incidental finding of a hyperfluorescent LN, harboring metastatic tumorous cells, around the inferior epigastric artery was made. Results In three out of five patients with clear fluorescent hotspot, the harvested LN was harboring metastatic cancerous cells. None of these nodes, whether negative or positive, was visible on any preoperative imaging modalities. A protocol to sample, in a systematic manner, the IELN in patients with PC, is currently being devised at our institution. Conclusion These lymphatic nodes basin and channels might reveal to be a potential passage from peritoneal metastasis to the extraperitoneal lymphatic compartment, representing an independent pathway for cancerous cell dissemination. This will bring us to further investigate the prevalence and the prognostic significance of these LNs.

Automated summary

This study reports a metastatic lymphatic pathway in patients with peritoneal carcinomatosis, which may represent a significant route for abdominal metastasis. Incidental findings of lymph nodes containing metastatic cancer cells were detected during surgery, which were not visible on preoperative imaging in some patients.