The Predictive Value of Albumin-to-Alkaline Phosphatase Ratio for Overall Survival of Hepatocellular Carcinoma Patients Treated with Trans-Catheter Arterial Chemoembolization Therapy

Background: We have previously reported the prognostic value of the albumin-to-alkaline phosphatase ratio (AAPR) for advanced hepatocellular carcinoma (HCC) patients who are not receiving any standard anticancer therapy. However, the prognostic value of the AAPR for HCC patients treated with trans-catheter arterial chemoembolization therapy (TACE) was not investigated. Methods: We retrospectively analysed 372 HCC patients treated with TACE (the training cohort) and applied receiver operating characteristic curves (ROC curves) to identify the best cut-off value for the AAPR in this cohort. Then, univariate analyses by the Kaplan-Meier method and multivariate analysis by a Cox proportional hazards regression model were conducted. Both comparisons of the ROC curves and the likelihood ratio test (LRT) were employed to evaluate the abilities of different factors in predicting the survival of patients in this cohort. Finally, the prognostic value of the AAPR was validated in two cohorts: one included 202 HCC patients treated with supportive care (validation cohort I), and the other included 82 HCC patients treated with TACE (validation cohort II). Results: We identified 0.439 as the best cut-off value of the AAPR by ROC curve analysis. An AAPR > 0.439 was significantly correlated with a lower frequency of Child-Pugh grade B, portal vein tumour thrombus (PVTT), T3-4 and lymph node metastasis (P < 0.05). The median overall survival (OS) of the patients with an AAPR > 0.439 was significantly longer than that of those with an AAPR ≤ 0.439 (58.4 m vs 17.8 m, respectively, P < 0.001). The AAPR was identified as an independent prognostic factor after univariate and multivariate analyses (HR = 0.636, P = 0.003). The independent prognostic value of the AAPR was also confirmed in validation cohorts I and II. Additionally, we substituted the AAPR for the Child-Pugh grade in the CLIP system and integrated the AAPR into the TNM system. We found that the area under the curve (AUC) of the AAPR-CLIP system was significantly larger than that of the CLIP and the TNM when predicting 3-month, 6-month, 1-year and 2-year survival (P < 0.05). There was no significant difference between the AUCs for the AAPR-CLIP and the AAPR-TNM. The LRT suggested that both AAPR-CLIP and AAPR-TNM had significantly larger χ2 values and smaller AIC values than that of their corresponding primary system (P < 0.05). Conclusions: The AAPR was an independent prognostic index for the HCC patients treated with TACE. Both AAPR-CLIP and AAPR-TNM outperformed their corresponding primary system in predicting OS in the current study.