Impact of microscopic hepatic lymph node involvement on survival after resection of colorectal liver metastasis

BACKGROUND: Macroscopic hepatic lymph node involvement is usually a contraindication to hepatic resection. Only a few studies have investigated the impact of hepatic lymph node involvement on survival. The aim of this retrospective study was to assess microscopic hepatic lymph node involvement in resectable colorectal liver metastasis and outcomes in patients with such involvement. STUDY DESIGN: From January 1985 to December 2000, 156 patients underwent curative liver resection in association with systematic hepatic lymph node dissection for colorectal liver metastasis. A first analysis was performed to assess the association between hepatic lymph node metastasis and patients' characteristics. A second analysis assessed survival after resection of liver colorectal metastasis by using the Kaplan-Meier method. RESULTS: Twenty-three of the 156 patients (15%) had microscopically involved hepatic lymph nodes. No predictive factor of lymph node metastasis was identified. Multivariate analysis showed that lymph node metastasis, preoperative carcinoembryonic antigen level, number of metastases, and morbidity were factors influencing survival. The 3- and 5-year survival rates of patients with lymph node metastasis were 27% and 5%, respectively, compared with 56% and 43% without lymph node metastasis (p = 0.0001). CONCLUSIONS: During resection of liver colorectal metastasis, microscopic lymph node involvement occurred in 15% of the patients and was associated with a poor 5-year survival. Hepatic lymph node dissection should be performed systematically to select high-risk patients.