Prognostic value of preoperative alpha-fetoprotein (AFP) level in patients receiving curative hepatectomy-an analysis of 1,182 patients in Hong Kong

Background: The value of alpha-fetoprotein (AFP) as a prognostic indicator in patients with hepatocellular carcinoma (HCC) has been proposed in recent studies, but the evidence so far is still contradictory. This analysis aims to evaluate the prognostic value of preoperative AFP level in patients undergoing curative resection. Methods: This retrospective study reviewed the prospectively collected data of all patients who underwent initial liver resection for HCC at Queen Mary Hospital during the period from March 1999 to March 2013. Patients with palliative resection, positive margin after pathological examination or distant metastasis were excluded from the study. Survival of patients with AFP level of <20, 20-400 and >400 ng/mL were compared with Kaplan-Meier analysis. Subgroup analysis was performed according to tumour stage (7th edition UICC staging) and tumour size. The optimal cutoff value was determined by area under receiver operating characteristic curve. Results: A total of 1,182 patients were included. Best overall (OS) and disease free survival (DFS) was observed in patients with AFP level <20 ng/mL. Progressively worse outcomes were seen for patients with increasing level of AFP. The median OS were 132.9, 77.2 and 38.4 months for patients with AFP <20, 20-400 and >400 ng/mL respectively (P<0.001). The median DFS for these three groups were 55.6, 25 and 8.4 months respectively (P<0.001). There was significant difference in both OS and DFS among all 3 groups. With subgroup analysis according to tumour stage (stage I and II versus stage III and IV) and tumour size (5 cm or less versus larger than 5 cm), such difference was still observed and remained statistically significant. Optimal cutoff value by discriminant analysis was 12,918.3 ng/mL for OS and 9,733.3 ng/mL for DFS. Conclusions: This study demonstrates that AFP is a significant prognostic indicator in HCC. Despite tumour stage and size, high level of AFP is associated with poorer OS and DFS. Whether the level of AFP should be included in current staging systems, or treatment protocols, is yet to be determined.