Abstract / Summary
Background: Recent studies have indicated that the treatment of inguinal lymph node metastasis (ILNM) and para-aortic lymph node metastasis (PALNM) in colorectal cancer could be curative. However, the optimal treatment approach remains unclear. Methods: A systematic search and a narrative review were undertaken to identify manuscripts reporting at least 10 patients with colorectal cancer treated with curative intent for ILNM or PALNM. Each study cohort was categorized into one of four treatment approaches: (1) surgery without radiotherapy; (2) radiotherapy followed by universal surgery; (3) radiotherapy followed by selective surgery; (4) definitive radiotherapy. Results and Conclusions: This review supports the use of curative-intent treatment in selected colorectal cancer patients with ILNM or PALNM. Surgery without radiotherapy is the most extensively studied approach. Lower recurrence rates have been reported in some retrospective series using preoperative radiotherapy followed by universal surgery, at the cost of acceptable additional toxicity. In some small studies, definitive radiotherapy has achieved recurrence rates in the range observed in surgical series, but direct comparisons are lacking. Radiotherapy followed by selective surgery may represent a potential strategy for achieving locoregional control while avoiding surgery in selected patients, but evidence is currently limited to two small studies of ILNM. In related clinical settings, such as nonoperative management of primary rectal tumors and lateral lymph node metastasis, treatment has shifted over the past decade toward radiotherapy followed by selective surgery. It is possible that a similar evolution will occur for ILNM and PALNM as well, but stronger evidence is required before firm recommendations can be made. Systemic therapy was not the focus of this review but should be considered an essential component for most patients, in addition to radiotherapy and surgery.