Comparison of various liver cancer staging systems in predicting prognosis after initial transcatheter arterial chemoembolization: a retrospective study from China

Abstract

Background: Hepatocellular carcinoma (HCC) constitutes approximately 75-85% of primary liver cancers and is a heavy burden on public health. Many innovative prediction systems have integrated radiomics, artificial intelligence, pathological information, or even genetic information for the stratification and prognosis prediction of patients with HCC. However, these systems still lack practical and clinical applications. Classical HCC staging systems remain the mainstream tool for stratification and prediction of treatment efficacy to date; although, variable characteristics and emphases between different classical HCC staging systems render its clinical selection inconsistent and therefore may be unreliable. In this study, we aimed to compare the predictive performance of classical liver cancer staging systems, including China Liver Cancer (CNLC), Barcelona Clinic Liver Cancer (BCLC), Hong Kong Liver Cancer (HKLC), modified Japanese Integrated Staging (mJIS), modified Cancer of the Liver Italian Program (mCLIP), and Tumor-Node-Metastasis (TNM) staging system, for the efficacy and prognosis of transcatheter arterial chemoembolization (TACE) in HCC patients.

Methods: A total of 148 patients with HCC who received TACE as the initial therapy between 02/01/2019 and 08/31/2022 were retrospectively included. Patients' clinical information, laboratory and imaging data, were collected. Cox regression analysis was applied to identify independent risk factors for progression-free survival (PFS) and overall survival (OS). Six liver cancer staging systems, including the CNLC, BCLC, HKLC, mJIS, mCLIP, and TNM staging system, were applied for the staging of every enrolled patient. The PFS and OS of patients with HCC following initial TACE in different staging systems were assessed, and the predictive performance of different systems was evaluated using the concordance index.

Results: The presence of portal vein tumor thrombus (PVT), alpha fetoprotein (AFP) ≥400 ng/mL, and ineffective initial TACE treatment were independent risk factors for overall disease progression, while the presence of PVT and ineffective initial TACE treatment were independent risk factors for death. In the prediction of PFS and OS, CNLC, BCLC, HKLC, mJIS, and mCLIP all showed good predictive ability, but the predictive ability of the TNM staging system was relatively poor.

Conclusions: The CNLC, BCLC, HKLC, mJIS, and mCLIP staging systems provide comparable predictive value for the prognosis after the initial TACE, while the TNM staging system has poor predictive ability due to its exclusion of hepatic function.

Keywords: C-index; PLC staging system; hepatocellular carcinoma (HCC); prognosis; transcatheter arterial chemoembolization (TACE).

Figure 1

Flowchart of patient inclusion. HCC, hepatocellular carcinoma; TACE, transcatheter arterial chemoembolization; PS, performance status.

Figure 2

The progression-free survival curves of patients with hepatocellular carcinoma in the various staging systems. (A) The PFS curve of CNLC stage Ia to IIIb. (B) The PFS curve of BCLC stage A to C. (C) The PFS curve of HKLC stage I to IVb. (D) The PFS curve of mJIS score 0 to 4. (E) The PFS curve of mCLIP score 0 to 5. (F) The PFS curve of TNM stage Ib to IV. PFS, progression-free survival; Mo, months; CNLC, Chinese liver cancer; BCLC, Barcelona Clinic Liver Cancer; HKLC, Hong Kong Liver Cancer; mJIS, modified Japanese Integrated Staging; mCLIP, modified Cancer of the Liver Italian Program; TNM, tumor-node-metastasis.

Figure 3

The overall survival curves of patients with patients with hepatocellular carcinoma in the various staging systems. (A) The OS curve of CNLC stage Ia to IIIb. (B) The OS curve of BCLC stage A to C. (C) The OS curve of HKLC stage I to IVb. (D) The OS curve of mJIS score 0 to 4. (E) The OS curve of mCLIP score 0 to 5. (F) The OS curve of TNM stage Ib to IV. OS, overall survival; Mo, months; CNLC, Chinese liver cancer; BCLC, Barcelona Clinic Liver Cancer; HKLC, Hong Kong Liver Cancer; mJIS, modified Japanese Integrated Staging; mCLIP, modified Cancer of the Liver Italian Program; TNM, tumor-node-metastasis.

Figure 4

Error bar plot of C-index and 95% CI for each staging system. (A) The C-index and 95% CI for predicting PFS. (B) The C-index and 95% CI for predicting OS. BCLC, Barcelona Clinic Liver Cancer; CNLC, Chinese liver cancer; HKLC, Hong Kong Liver Cancer; mCLIP, modified Cancer of the Liver Italian Program; mJIS, modified Japanese Integrated Staging; TNM, tumor-node-metastasis; C-index, concordance index; CI, confidence interval; PFS, progression-free survival; OS, overall survival.