Abstract
〈BACKGROUND〉Endoscopic mucosal resection or laparoscopic wedge resection (minimally invasive surgery) have been performed for patients with early mucosal gastric cancer, preserving of gastric function to maintain patients'QOL. It will be important to clarify clinico-pathological risk factors of lymph node (LNs) metastasis, especially in mucosal gastric cancer, in order to keep curability for minimally invasive surgery.〈PURPOSE〉We evaluate clinico-pathological features and LNs metastasis in mucosal gastric cancer retrospectively, to identify critical risk factors of LNs metastasis. In addition, we demonstrate sentinel node navigation surgery (SNNS) for mucosal gastric cancer in our department.〈PATIENTS AND METHODS〉We investigated 476 patients who are pathologically diagnosed as mucosal gastric cancer after gastrectomy with LNs dissection between January, 1992 and December, 2001. Clinico-pathological features (tumor size, macroscopic type, histological type, tumor location, presence of ulcer scar) were evaluated, accoding to existence of LNs metastasis.〈RESULTS〉Ten patients were diagnosed mucosal gastric cancer with LNs metastasis (2.1%) . All 10 cases showed depressed type in macroscopic type and M or L region in tumor location. In histological type, differentiated type, undifferentiated type and squamous cell carcinoma were 2, 7 and 1 cases, respectively. Seven cases were diagnosed as N1 LNs metastasis, and 3 cases as N2. Incidence of LNs metastasis in tumor with ulcer scar (5.3%) is significantly higher than that in tumor without ulcer scar (1.5%) . Thus, undifferentiated type and ul (＋) was determined as critical factors of LNs metastasis in mucosal gastric cancer. On the other hand, we performed SNNS with gastrectomy in 40 cases of mucosal gastric cancer, and only a case showed LNs metastasis (N2) . Six LNs of N1 (4 LNs) and N2 (2 LNs) were detected as SNs, intraoperatively, and the 6 LNs were determined as LNs metastasis by pathological diagnosis.〈CONCLUSION〉We demonstrated critical risk factors of LNs metastasis in mucosal gastric cancer, and undifferentiated type and ul (＋) tumor should be treated with curative surgery with LNs dissection. In addition, clinical usefulness of SNNS for prediction of LNs metastasis in early gastric cancer was shown, evaluating 40 cases of mucosal gastric cancer.
