Background: Forty percent of patients with gastric cancer have unnecessarily extended lymph node dissections with higher rates of morbidity and mortality than those in non-extended procedures. Successful sentinel lymph node (SLN) mapping may help to reduce the number of extended lymphadenectomies.
Methods: SLN mapping was investigated by a blue dye-only method in patients with gastric cancer. The first cohort of patients (n = 16) were marked submucosally by an endoscopist and in the second cohort of patients (n = 23) a subserosal injection was performed by the surgeon.
Results: Thirty-nine patients, all Caucasians, underwent gastric resection or total gastrectomy with SLN biopsy using patent blue-dye mapping and modified D2 lymphadenectomy. The mapping procedure and the lymphadenectomy were supervised by the same surgeon. A total of 770 lymph nodes were removed and examined. The mean number of blue nodes was 4.3 per patient. In 22/23 cases at least one SLN showed tumor involvement. The sensitivity of SLN mapping was 95.7%, the false-negative rate was 4.3%, and the specificity was 100%. The negative predictive value was 93.8% and the positive predictive value was 100%. In cases of T1 and T2 tumors the sensitivity was 100%. We found the two marking methods (submucosal vs. subserosal) to be equivalent and there was no side-effect of the blue-dye mapping.
Conclusions: Our results suggest that SLN mapping with blue dye alone represents a safe procedure that seems to be adaptable for non-obese patients undergoing open surgery for gastric cancer in the Eastern European region. The procedure has high sensitivity and specificity, especially in cases of T1 and T2 tumors.