RA08.02: RELATIONSHIP BETWEEN ABDOMINAL FAT DISTRIBUTION AND VASCULAR INVASION AMONG PATIENTS WITH EARLY ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Background Excessive visceral fat might promote cancer development and progression because of metabolic disruption. A previous study has demonstrated that visceral obesity associated with lymphatic invasiveness and a poor response to preoperative treatment among patients who underwent esophagectomy for advanced esophageal squamous cell carcinoma (ESCC). This study aimed to clarify the impact of abdominal fat distribution on lymphatic and vessel invasion after endoscopic submucosal dissection (ESD) or esophagectomy for early ESCC (eESCC). Methods We enrolled the 106 patients who had undergone ESD or curative esophagectomy for pathological T1-muscularis mucosa (MM) and T1-submucosal layer (SM) lesions between January 2015 and December 2016. Using computed tomography volumetry, we measured areas of visceral (VFA) and subcutaneous (SFA) fat at the level of the umbilicus, and calculated the VFA/SFA ratio in each patient. We also measured body mass index (BMI). Lymphatic and vessel invasion by eESCC were compared with these parameters and between groups classified according to VFA/SFA ratios. Results Significantly more patients in the T1-MM group with high VFA/SFA had lymphatic invasion of eESCC compared with those who had low VFA/SFA (35.7% vs. 7.1%, P = 0.010). Metastatic lymph nodes were detected only in patients with high VFA/SFA who underwent esophagectomy. Values for BMI, VFA, and SFA were lower in patients with venous invasion than those without (BMI, 20 vs. 22.8, P = 0.076; VFA, 60.2 vs. 98.9 cm2, P = 0.042; SFA, 56.3 vs. 103.2 m2, P Conclusion High VFA/SFA ratio was significantly associated with lymphatic invasion in patients with eESCC. Low values of BMI, VFA, and SFA was significantly associated with venous invasion in patients with eESCC. Abdominal fat distribution might influence lymphatic and vessel invasion by eESCC. Disclosure All authors have declared no conflicts of interest.