Alkaline Phosphatase to Albumin Ratio: A Novel Prognostic Biomarker for Hepatocellular Carcinoma after Microwave Ablation as the Initial Treatment

Background: As a new serum-based biomarker, albumin to alkaline phosphatase ratio (AAPR) has been studied among several cancers. However, alkaline phosphatase to albumin ratio (APAR) has not been investigated among hepatocellular carcinoma (HCC) patients undergoing microwave ablation (MWA) as the initial therapy. Methods 228 HCC patients undergoing MWA as the initial treatment were included in this study. Firstly, receiver operating curve (ROC) analysis was performed to identify the optimal cutoff values for APAR and other biomarkers. Then, the associations between APAR and clinicopathological variables were assessed. Additionally, Kaplan-Meier analysis was accomplished to evaluate the impacts of APAR on prognosis of HCC patients. Ultimately, Cox regression analysis was performed to identify independent prognostic factors for HCC patients. Results It was initially revealed that the optimal cutoff value for APAR was 2.44 (P < 0.001). Then it was demonstrated that high APAR was significantly associated with tumor size (P = 0.043). Subsequently, through Kaplan-Meier analysis, it was revealed that high APAR was significantly associated with worse overall survival (OS, P < 0.001) and disease-free survival (DFS, P < 0.001). Ultimately, along with tumor size (P = 0.018, HR = 2.292, 95%CI: 1.152–4.561), high APAR (P < 0.001, HR = 5.881, 95%CI: 3.093–11.185) was demonstrated to be an independent predictive factor for overall survival (OS). Similarly, along with Child-Pugh grade (P = 0.001, HR = 3.467, 95%CI: 1.705–7.050), GAR (P = 0.004, HR = 2.152, 95%CI: 1.281–3.613), and number of tumors (P = 0.015, HR = 2.678, 95%CI: 1.213–5.917), high APAR (P = 0.032, HR = 1.572, 95%CI: 1.040–2.377) was demonstrated to be an independent predictive factor for disease-free survival (DFS). Conclusion APAR was a reliable biomarker predicting survival of HCC patients.