# Photon-Counting Detector Computed Tomography and Hepatocellular Carcinoma—A Systematic Review of the Current Evidence

## TL;DR

This review evaluates how photon-counting CT improves imaging of liver cancer, showing promise for better detection and image quality.

## Contribution

The paper systematically reviews PCCT's technical advancements for hepatocellular carcinoma imaging.

## Key findings

- 50 keV reconstructions improve lesion conspicuity in PCCT for HCC.
- Quantum iterative reconstruction reduces noise and enhances image quality.
- Dual-contrast PCCT is feasible for simultaneous arterial and portal-phase imaging.

## Abstract

Objectives: The aim of this systematic review was to evaluate the current evidence on photon-counting detector computed tomography (PCCT) in hepatocellular carcinoma (HCC) imaging. Methods: A systematic literature search was performed in PubMed and Scopus, and five articles were finally included. Results: Four studies focused on the optimization of acquisition and reconstruction parameters such as slice thickness, kernels, virtual monoenergetic imaging (VMI), and quantum iterative reconstruction (QIR), with 50 keV reconstructions consistently associated with improved lesion conspicuity. QIR demonstrated significant noise reduction compared with filtered back projection, enhancing overall image quality, while one proof-of-concept study investigated dual-contrast PCCT, showing feasibility for simultaneous arterial and portal-phase acquisition. According to QUADAS-2, most studies presented a low or unclear risk of bias, with only one study rated at high risk for patient selection. Conclusions: In conclusion, PCCT shows promising technical advances and potential for improved HCC detection and characterization. Current evidence remains preliminary and focused on image quality rather than clinical outcomes; PCCT applications in routine practice are still largely unexplored.