Among 229 patients who underwent Hx from January 2006 to December 2014, 162 patients were enrolled in this study. Inclusion criteria of this study were 1) Primary Hx, 2) No any other treatments before Hx, 3) Availability of follow up data. The study was approved by Tokushima University Hospital ethics committee and with the approval of corresponding regulatory agencies, and all the experiments were carried out in accordance with the approved guidelines (Tokushima Clinical Trial Management System Number; 3215). Meanwhile, all the patients involved in the study signed the informed consent form and agreed to participate.
Preoperative immune parameters
Blood samples were taken prior to Hx. The PNI was the sum of serum albumin and 0.005×lymphocyte count. The NLR was calculated by dividing neutrophil count by lymphocyte count. ALRI was calculated by dividing AST by lymphocyte count. The cutoff value of PNI, NLR and ALRI was 45, 2.3 and 30.8 calculated by receiver-operating characteristic (ROC) curve for predicting recurrence after Hx.
Assessment of fat mass (FM) and skeletal muscle mass (SMM)
Preoperative fat mass (FN) or skeletal muscle mass (SMM) was investigated from CT modality using Synapse Vincent®. Visceral FM (cm2), subcutaneous FM (cm2) and SMM / height (cm2 / m2) were automatically calculated.
Follow-up after Hx
Monthly follow-up was conducted by assessment of tumor markers (AFP, DCP, and AFP-L3) and ultrasonography. Dynamic computed tomography (CT) scan and Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) were conducted at 3 and 6 months post operation. We defined recurrence as the appearance of new lesions with radiological features typical of HCC, as confirmed by at least two imaging methods.
All statistical analysis was performed using SPSS Version 21.0 statistical software (SPSS, Chicago, IL). A p-value of less than 0.05 was considered statistically significant. Relationships between PNI and the clinicopathological variables were analyzed using the chi-square test and Mann-Whitney U test. Survival curves were calculated using the Kaplan-Meier method and compared with the log-rank test. All factors significant by univariate analysis were included in the Cox’s proportional hazards model of multivariate analysis to identify independent factors influencing survival. The factors included for analyses were patient age (under 70 / over 70 y.o.), gender (male / female), HBsAg (absent / present), HCVAb (absent / present), AFP (under 200 / over 200 ng/ml), DCP (under 400/over 400 mAU/ml/), yumor number (single / multiple), tumor size (under 3 / over 3cm), tumor differentiation (well, moderate / poor), portal invasion (absent / present), staging (I,Ⅱ / Ⅲ,Ⅳ) and PNI (high / low).