Sentinel lymph node mapping with technetium-99m colloidal rhenium sulfide in patients with gastric carcinoma

Background The objective of this study was to determine, with the use of technetium-99m colloidal rhenium sulfide, whether the concept of sentinel lymph nodes (SLNs) is applicable to gastric cancers. Methods Fifty-nine gastric cancer patients underwent radical gastrectomy and SLN mapping with an intraoperative hand-held γ probe. After surgery, each transected lymph node was measured for radioisotope (RI) activities by a well-type scintillation counter. Results SLNs were detectable in 57 (96%) of 59 patients. The sensitivity, specificity, and diagnostic accuracy were calculated to be 83.3%, 100%, and 92.9%, respectively. Sensitivity was 100% in the T1 group, 91.6% in the T2 group, and 62.5% in the T3 group. When RI activities were measured with a well-type scintillation counter, every metastatic non-SLN was found to be situated in the same lymphatic basin as the SLNs. Conclusion The SLN concept is applicable to patients with early gastric cancer (T1). SLN mapping is suitable for identifying the lymphatic basin in cases of gastric cancer.