Retrospective Cohort Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Feb 27, 2018; 10(2): 308-318
Published online Feb 27, 2018. doi: 10.4254/wjh.v10.i2.308
Survival outcomes of liver transplantation for hepatocellular carcinoma in patients with normal, high and very high preoperative alpha-fetoprotein levels
Wong Hoi She, Albert Chi Yan Chan, Tan To Cheung, Chung Mau Lo, Kenneth Siu Ho Chok
Wong Hoi She, Department of Surgery, University of Hong Kong, Hong Kong, China
Albert Chi Yan Chan, Tan To Cheung, Chung Mau Lo, Kenneth Siu Ho Chok, Department of Surgery and State Key Laboratory for Liver Research, University of Hong Kong, Hong Kong, China
Author contributions: She WH contributed to study conception and design, data acquisition, analysis, interpretation and manuscript drafting; Chan ACY, Cheung TT and Lo CM contributed to critical revision of the manuscript; Chok KSH contributed to study conception and design, drafting and revision of the manuscript; all authors approved the submitted version of the paper.
Institutional review board statement: Institutional review board approval was not required for this retrospective study since treatments given to patients were not influenced by the study and the clinical data used in the study are anonymous.
Informed consent statement: Patients’ consent to this retrospective study was not required since treatments given to patients were not influenced by the study and no individual patients would be identified as the clinical data used in the study are anonymous.
Conflict-of-interest statement: None of the authors has any conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Kenneth Siu Ho Chok, FRCS (Ed), Associate Professor, Department of Surgery, University of Hong Kong, 102 Pok Fu Lam Road, Hong Kong, China. chok6275@hku.hk
Telephone: +852-22553025 Fax: +852-28165284
Received: November 23, 2017
Peer-review started: November 24, 2017
First decision: December 12, 2017
Revised: December 18, 2017
Accepted: February 5, 2018
Article in press: February 5, 2018
Published online: February 27, 2018
Processing time: 101 Days and 5.9 Hours
Abstract
AIM

To investigate the impact of alpha-fetoprotein (AFP) on long-term recurrence rate and overall survival and we also aimed to define the level of AFP leading to a higher risk of disease recurrence and affecting patient survival.

METHODS

Data of adult patients who received liver transplant (LT) for hepatocellular carcinoma (HCC) at our hospital from January 2000 to December 2013 were reviewed. Reviewed data included demographic characteristics, preoperative AFP level, operative details, follow-up details, and survival outcomes. Patients were mostly listed for LT based on Milan or UCSF criteria. For the purpose of this study, normal AFP level was defined as AFP value < 10 ng/mL, high AFP level was defined as AFP value ≥ 10 to < 400 ng/mL, and very high AFP level was defined as AFP ≥ 400 ng/mL. The patients were divided into these 3 groups accordingly. Survival rates were plotted as Kaplan-Meier curves and compared by log-rank analysis. Continuous variables were expressed as median (interquartile range). Categorical variables were compared by Spearman’s test. Discriminative analysis was used to define the lowest value of AFP that could affect the overall survival in study population. Statistical significance was defined by a P value of < 0.05.

RESULTS

Totally 250 adult patients underwent LT for HCC in the study period. Eight-four of them received deceased-donor LT and 166 had living-donor LT. The patients were divided into 3 groups: Group A, AFP < 10 ng/mL (n = 83); Group B, AFP ≥ 10 to < 400 ng/mL (n = 131); Group C, AFP ≥ 400 ng/mL (n = 36). The commonest etiology was hepatitis-B-related cirrhosis. The Model for End-stage Liver Disease scores in these groups were similar (median, 13 vs 13 vs 12; P = 0.745). The time to operation in Group A was longer (median, 94 vs 31 vs 35 d; P = 0.001). The groups were similar in hospital mortality (P = 0.626) and postoperative complication (P = 0.702). Pathology of explants showed that the 3 groups had similar numbers of tumor nodules, but the tumors in Group C were larger (A: 2.5 cm, B: 3.0 cm, C: 4.0 cm; P = 0.003). Group C had a bigger proportion of patients who were beyond Milan criteria (P = 0.010). Poor differentiation and vascular permeation were also more common in this group (P = 0.017 and P = 0.003 respectively). It also had poorer 5-year survival (A: 85.5%, B: 82.4%, C: 66%; P = 0.029). The 5-year disease-free survival was 84.3% in Group A, 80.1% in Group B, and 61.1% in Group C. Receiver operating characteristic area under the curve for AFP in predicting tumor recurrence was 0.685. The selected cut-off value was 54 ng/mL for AFP (C-index 0.685; 95%CI: 0.592-0.779; sensitivity 0.595; specificity 0.687). On discriminative analysis, AFP value of 105 ng/mL was shown to affect the overall survival of the patients.

CONCLUSION

HCC patients with a high preoperative AFP level had inferior survival after LT. AFP level of 54 ng/mL was associated with disease recurrence, and AFP level of 105 ng/mL was found to be the cut-off value for overall survival difference.

Keywords: Alpha-fetoprotein; Liver transplantation; Recurrence; Survival

Core tip: Various established criteria have been used to identify patients with hepatocellular carcinoma who would benefit from liver transplant with reasonable survival. Alpha-fetoprotein (AFP) level has been identified as an important factor associated with suboptimal survival with high recurrence rate. This study demonstrated that AFP level correlated well with the pathological findings of tumor differentiation and microvascular invasion, which are usually confirmed in explant pathology. In this set of data, AFP level of 54 ng/mL was associated with disease recurrence, and AFP level of 105 ng/mL was found to be the cut-off value for overall survival difference.