Results of lymphadenectomy for obvious lateroaortic lymph node metastases from colorectal primaries.

Background/Aims: To analyze the results of surgery for macroscopically or radiologically obvious (i.e., easily detectable by computed tomography scan or by palpation) synchronous or metachronous lateroaortic lymph node metastases from colorectal primaries. Methodology: Thirty-one highly selected patients who underwent a lateroaortic lymphadenectomy for obvious lateroaortic lymph node metastases from January 1989 to January 1999 were analyzed retrospectively. An associated metastatic lesion was present in 68% of the cases before or concomitantly with the lateroaortic lymph node metastases. Ten lateroaortic lymph node metastases were synchronous with the primary, and 21 were metachronous. Decision for lymphadenectomy was taken after a multidisciplinary meeting and a period of observation. Median follow-up after lymphadenectomy was 24.2 months (range: 6-120). All the patients received at least two systemic lines of chemotherapy before or after the lateroaortic lymphadenectomy. Results: There was no postoperative mortality. Resection was macroscopically complete (R0-1 of UICC) in 26 cases (84%). Twenty-six (83.8%) patients developed recurrent lesions or had progressive residual disease. The most frequent first site of recurrence was intrathoracie (54.8%) for the entire series, except for the subgroup of isolated lateroaortic lymph node metastases in which recurrent lesions were mainly lateroaortic. Three-year global and disease-free survival rates were, respectively, 39% and 9.6%. No significant difference was noted in survival between lateroaortic lymph node metastases that were synchronous or metachronous with the primary. However, the most important prognostic factor was the presence of associated metastases. Indeed 3-year survival attained 30% when lateroaortic lymph node metastases were isolated but 0% when lateroaortic lymph node metastases were associated with another metastatic site (P=0.006). Conclusions: Obvious lateroaortic lymph node metastasis is rarely isolated. However, when it is isolated, in selected cases (objective response to systemic chemotherapy, good general status), resection can be beneficial whatever its synchronous or metachronous appearance.