Background: Sentinel node (SN) biopsy has been tried in the management of a variety of cancers with the hope that it would eliminate many unnecessary lymph node dissections, resulting in less morbidity. This important technique, however, has not been tried in gastric cancer surgery. The feasibility of SN biopsy and its accuracy in predicting the lymph node status in patients with gastric cancer were examined in the current study.
Patients and methods: SN biopsy was performed in patients with T1 (n = 44) or T2 (n = 30) gastric cancers (ie, immediately after laparotomy, indocyanine green was injected around the primary tumor, and the green-stained nodes [SNs: 2.6 +/- 1.7 nodes per patient] were removed). Then, gastrectomy with extended lymphadenectomy was performed. The unstained nodes (non-SNs: 39 +/- 18 nodes per patient) were obtained from the resected specimens. Both SNs and non-SNs were subjected to histologic examination with hematoxylin-eosin.
Results: SNs could be identified in 73 of 74 patients (success rate, 99%). Of these 73 patients, 10 had lymph node metastases in SNs or non-SNs, or both; 6 in both SNs and non-SNs; 3 in SNs alone; and 1 in non-SNs alone. The sensitivity of the SN status in the diagnosis of the lymph node status of the patient was 90% (9/10) and specificity was 100% (63/63). Sensitivity was 100% in the T1 group (n = 44) and 88% in the T2 group (n = 29).
Conclusions: SN biopsy using indocyanine green can be performed with a high success rate, and the SN status can predict the lymph node status with a high degree of accuracy, especially in patients with T1 gastric cancer.