Diagnosis and impact of hilar lymph node micrometastases on the outcome of resected colorectal liver metastasis.

BACKGROUND/AIMS: Liver resection is the only curative therapy for metastatic colorectal cancer. However, recurrence occurs in the majority of the cases. Hilar lymph node metastases occur with a high frequency but the methodology for its detection and the impact on the outcome of patients undergoing hepatectomy is still unknown.

METHODOLOGY

Twenty-six patients submitted to partial liver resection and systematic lymphadenectomy were studied prospectively. Lymph nodes considered negative by hematoxylin and eosin (H&E) staining were analyzed by serial sectioning and immunohistochemistry (IHC) with anti-human pancytokeratin antibody AE1/AE3. Recurrence-free and overall survivals were compared among LN groups.

RESULTS

The mean number of dissected lymph nodes were 6.3 per patient. H&E showed microscopic involvement of LN in 2 patients and 3 patients had metastases identified only by IHC. The median follow-up was 39.3 months. Sixteen patients (61.5%) recurred after liver resection and although no statistical difference in survival was demonstrated there was a trend towards shorter recurrence-free survival among microscopic positive LN.

CONCLUSIONS

Microscopic LN metastases may have impact in the outcome of patients submitted to curative hepatectomy. A better definition of micrometastases to LN is warranted, as though the potential benefit of hilar lymphadenectomy and chemotherapy selection by hilar lymph node status.