Lateral pelvic lymph node dissection for advanced lower rectal cancer

Background: The oncological outcome of patients who underwent curative surgery for lower rectal cancer was investigated to clarify whether lateral pelvic lymph node dissection (LPLD) conferred any benefit. Methods: A total of 246 patients who underwent curative surgery for stage II and III lower rectal cancer (below the peritoneal reflection) between 1985 and 1998 was reviewed. Forty-two of these patients did not undergo LPLD. Results: Patients who did not undergo LPLD were older, more likely to have anterior resection and pelvic nerve preservation, and had smaller tumours and lymph node metastasis at an earlier stage than those who underwent LPLD. There was no difference in survival among patients with stage II and III disease between the two groups. However, in patients with pathological N1 lymph node metastasis, the 5-year disease-free survival rate was 73.3 percent in patients who had LPLD compared with 35.3 per cent among those who did not (P = 0.013). Multivariate analysis showed that LPLD was a significant prognostic factor. Conclusion: LPLD improved the prognosis of patients with stage III disease and a small number of lymph node metastases. A randomized clinical trial is needed to verify the benefit of LPLD.