Background: The relationship between fat distribution and lymph node metastasis has not been well studied. The goal of this study was to determine the impact of visceral obesity on lymph node metastasis in gastric cancer.
Materials and methods: Metastatic lymph node ratio (MLR) was defined as the number of involved nodes by tumor divided by the total number of resected lymph nodes. Visceral (VFA) and subcutaneous fat areas (SFA) were determined by measuring abdominal fat volume distribution via CT scan, and visceral obesity was defined as a VFA to total fat area ratio (V/T) >0.29.
Results: With lymph node metastasis as a dependent variable, the following factors were significant in multivariate analysis among 495 patients: pathologic T stage (P < 0.001), lympho-vascular invasion (P < 0.001), and V/T (hazard ratio (HR) = 0.455, 95 % confidence interval (CI) = 0.263-0.786, P = 0.005). Similarly, when MLR was the dependent variable in multivariate analysis, MLR was significantly associated with lympho-vascular invasion (HR = 2.222, 95 % CI = 1.149-4.296, P = 0.018), and V/T (HR = 0.247, 95 % CI = 0.133-0.458, P < 0.001).
Conclusions: Visceral obesity defined by higher visceral to total fat area ratio was significantly associated with decreased MLR.