Sentinel lymph node biopsy in gastric cancer: possible applications and limits

Abstract

Aims: To explore the feasibility and accuracy of sentinel lymph node (SLN) biopsy in gastric cancer.

Patients and methods: Twenty-nine patients with clinical T1 and T2 N0 M0 gastric cancer less than 5 cm in diameter underwent SLN biopsy with the intraoperative Patent blue method. The procedure continued with radical gastrectomy and D2 lymphadenectomy. We investigated all technical aspects of the blue dye technique and determined the accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the SLN technique.

Results: SLNs were detected in 28 of 29 patients; the total number of excised SLNs was 45, with a median of two (range 1-3). Seventeen patients had metastatic SLN, with 21 lymph nodes retrieved. Twenty-two patients had SLNs located at the first level. Four patients had SLNs at the second level, one at the first and second levels, and one at the first and third levels. Five patients had false negative SLNs. The ability of SLN biopsy to predict the status of the other lymph nodes was summarised by an accuracy of 75%, a sensitivity of 75%, a specificity of 75%, a positive predictive value of 88%, and a negative predictive value of 55%.

Conclusions: Our study demonstrates that pick-up SLN biopsy in gastric cancer is technically feasible but has very low sensitivity. Regarding the utility of SLN navigation when attempting to detect the nodal basin, the high rate of false negative SLNs and lymph node level jumping warrant further studies with a large accrual before the method can be introduced into daily practice.