Preoperative lymphoscintigraphy for detection of sentinel lymph node in patients with gastric cancer - Initial experience

Background: Preoperative lymphoscintigraphy may be informative when assessing nodal status in patients with early gastric cancer, especially for surgeons who are scheduled to introduce or have just introduced SLN biopsy. Methods: A total of 80 patients with clinical T1N0M0 gastric cancer were injected with technetium-99 m tin-colloid and then underwent preoperative lymphoscintigraphy. The detection rate of SLN per lymphatic basin was determined on the basis of the results of confirmatory lymph node dissection. Results: By means of lymphoscintigraphy, 71 of 106 basins were found (67%; 95% confidence interval [CI], 57.2-75.9%). Patients were stratified into the following subgroups: successful (S; all basins visualized), partially successful (PS; some basins visualized), and unsuccessful (U; none visualized). The body mass index (BMI) was significantly higher in the U (24.0 ± 2.5) than in the S (22.3 ± 2.4) group (P = 0.037). All patients in the U group had a single basin. Multivariate analysis showed that BMI was associated with unsuccessful lymphoscintigraphy (OR, 1.43; 95% CI, 1.06-1.92; P = 0.019), whereas all factors were similar between the S and PS groups. Conclusion: BMI affects SLN detection during lymphoscintigraphy. Unsuccessful lymphoscintigraphy suggests that SLNs are located in a single basin. When lymphoscintigraphy is positive, no preoperative factors can predict whether all lymphatic basins can be visualized.