Precisely 265 HCC patients, including 231 males and 34 females (median age=51 yrs) [range: 21–77 yrs] were enrolled. A total of 60, 62, 46, 52, and 45 patients were classified in groups I, II, III, IV, and V, respectively. Those whose tumors were ≤ 7 cm presented a higher albumin level, a longer survival time, and a higher proportion of ALBI grade 2 HCC than those who had tumors that were > 7 cm (P=0.010, P<0.001& P=0.036, respectively). However, patients who had tumor size ≤ 7 cm had a significantly low platelet count, a small tumor size, a short operative time, low blood loss, low rates of ALBI grade 1 HCC, AFP ≥ 400 ng/mL, major liver resection, and poor differentiation (P<0.001, P< 0.001, P=0.015, P<0.001, P=0.036, P=0.013, P<0.001, & P=0.015, respectively). The baseline features of participants are presented in Table 1.
Of the 265 patients, 95 (35.8%) experienced postoperative complication, including grade I complication in 30 (11.3%) patients, grade II complication in 49 (18.5%) patients, grade III complication in 13 (4.9%) patients, grade IV complication in 3 (1.1%) patients. Two patients died within 60 days after surgery, with a postoperative mortality rate of 0.75%.
Among the 265 patients, the OS at 1 and 3 years reached 92.8% and 66.8%, respectively. No considerable differences in the OS were observed between the groups I and II (P = 0.525), groups II and III (P = 0.439), and groups 1 and III (P =0 .627) (Figure 1A). A similar OS was noted between groups IV and V (P = 0.425, Figure 1B). However, the OS among patients with tumors size ≤ 7 cm was considerably longer compared to those who had tumor size > 7 cm (P<0.001, Figure 1C).
Evaluation of OS by multivariate analysis
The Cox proportional hazards regression model assessment of the total cohort identified three indices as independent predictive factors for OS: ALBI grade (hazard ratio (HR): 2.10; 95% confidence interval (CI): 1.43–3.08; P<0.001), maximum tumor size (HR: 1.72; 95% CI: 1.16–2.56; P=0.007), differentiation grade (HR: 1.47; 95% CI: 1.01–2.15; P=0.045) (Table 2).
In the subgroup that had tumor size ≤ 7 cm, the independent predicting factors for OS included the ALBI grade (HR: 2.37; 95% CI: 1.39–4.05; P=0.002) and platelet count (HR: 1.80; 95% CI: 1.07–3.05; P=0.027). But in the subgroup with tumor size > 7 cm, ALBI grade was not identified as a major determinant of OS (Table 3).
Comparison of overall survival of patients with ALBI grades 1 and 2 HCC stratified by tumor size
For the total cohort, we observed a remarkable difference in the OS between ALBI grades 1 and 2 patients (Figure 2F). For groups 1, II, and III, the ALBI grade 1 patients showed a significantly longer survival relative to the ALBI grade 2 patients (P=0.006, P=0.025, and P=0.039; Figures 2A, 2B, and 2C, respectively). However, the OS was comparable between patients in ALBI grades 1 and 2 in groups IV and V (P=0.546 and P=0.224; Figures 2D and 2E, respectively).
Comparison of patients’ overall survival in tumor size ≤ 7 cm + ALBI grade 1 vs. tumor size ≤ 7 cm + ALBI grade 2 vs. tumor size > 7cm subgroups
Given their importance in predicting OS, we further evaluated the effects of tumor size and ALBI grade on the HCC patient prognosis. With regards to size of tumor and ALBI grade, considerable differences in the OS were observed among the three patient subgroups (Figure 3). The tumor size ≤ 7 cm + ALBI grade 1 subgroup presented a remarkably higher OS compared to the tumor size ≤ 7 cm + ALBI grade 2 and tumor size > 7 cm subgroups. The patients in the tumor size > 7 cm subgroup exhibited the poorest OS among the three subgroups.
Discriminative ability of different scoring systems for patients’ survival
ROC curve analyses of ALBI score, Child-Pugh score and CLIP score were performed to predict 1-year survival and 3-year survival. The area under the ROC curve (AUC) for ALBI score, Child-Pugh score and CLIP score were 0.640 (P=0.043), 0.590 (P=0.191), 0.617 (P=0.090) in predicting 1-year survival (Figure 4A), and 0.645 (P<0.001), 0.580 (P=0.034), 0.584 (P=0.025) in predicting 3-year survival (Figure 4B).