Sentinel node mapping and skip metastases in patients with early gastric cancer.

OBJECTIVES

This study was designed to identify the characteristics of patients with early gastric cancers that have skip metastases.

BACKGROUND

The possibility of lymph node metastasis is the most important factor to consider when deciding on the resection procedure for patients with early gastric cancer.

METHODS

From February 2003 through July 2008, 739 patients with early gastric adenocarcinoma underwent gastric resection at the National Cancer Center, Korea, and were included in this study. Patients with skip metastases were analyzed and compared with those without skip metastases.

RESULTS

Skip metastases were found in 2.8% of patients with early gastric cancer. Tumor size and the presence of lymphatic invasion were associated with skip metastases by both univariate and multivariate analysis. All skip metastases were metastases to the extraperigastric lymph nodes that skipped across the perigastric lymph nodes. Sixteen patients (66.7%) with these metastases had metastatic lymph nodes at No. 7, 8, and 9 stations.

CONCLUSIONS

Tumor size should be considered during sentinel lymph node mapping to prevent false-negative results in patients with early gastric cancer. If sentinel nodes are not found in the perigastric lymph nodes, No. 7, 8, and 9 stations should be explored for prevention of false-negative sentinel node mapping results.