# Improved preoperative clinical staging system for intrahepatic cholangiocarcinoma using the ABC factors: a retrospective study

## TL;DR

This study improves preoperative staging for intrahepatic cholangiocarcinoma by incorporating anatomical, biological, and patient condition factors to predict survival outcomes.

## Contribution

The ABC staging system is introduced as a novel method combining anatomical, biological, and performance status factors for intrahepatic cholangiocarcinoma prognosis.

## Key findings

- ABC factors (anatomy, CA19-9, performance status) are independent predictors of overall and disease-free survival in ICC patients.
- Higher ABC composite scores correlate with significantly shorter median survival times.
- Incorporating CA19-9 and performance status improves preoperative staging accuracy beyond radiological findings.

## Abstract

This study aimed to assess the prognostic significance of ABC factors, including anatomical factors (A), biological factors (B: carbohydrate antigen 19–9 [CA19-9]), and patient condition (C) or performance status (PS), in intrahepatic cholangiocarcinoma (ICC) patients who underwent surgery, with the ultimate goal of enhancing the preoperative clinical staging system for the diagnosis of ICC.

We retrospectively analyzed the clinical data of 217 patients who underwent radical surgery for intrahepatic cholangiocarcinoma at the Zhejiang Cancer Hospital between January 2010 and August 2022. All patients were stratified into early (EA), intermediate (IM), and locally advanced (LA) stages, according to radiological findings. Multivariate Cox proportional hazards analysis was used to examine the impact of ABC factors on overall survival (OS) and disease-free survival (DFS).

Overall, 107 (49.3%), 86 (39.6%), and 24 (11.1%) patients were diagnosed with EA, IM, and LA, respectively. The preoperative CA19–9 level in 73 patients (33.6%) was >500 U/mL. The performance status score of 53 patients (24.4%) was ≥1. The independent risk factors for OS and DFS were IM, LA, CA19-9 >500 U/mL and performance status score ≥1. The median OS was 32.2, 20.4, 11.0, 9.8, and 6.8 months and the median DFS was 19.3, 14.8, 7.7, 5.9, and 3.3 months for patients with ABC composite scores of 0 to 4.

ABC is an independent prognostic factor for OS and DFS in patients undergoing radical surgery for ICC. The preoperative clinical staging of patients with ICC should fully consider the anatomical, biological, and PS factors.