# Prognostic difference between surgery and external radiation in patients with stage I liver cancer based on competitive risk model and conditional survival rate

## TL;DR

This study compares the long-term survival outcomes of surgery and radiation for early-stage liver cancer patients using survival models and risk analysis.

## Contribution

The study introduces a conditional survival analysis and competitive risk model to compare surgery and radiation for stage I liver cancer.

## Key findings

- Surgery showed better survival improvement than external beam radiation for stage I liver cancer patients.
- Conditional survival curves showed surgery had slower decline and stabilized around 3 years, while radiation declined sharply within 4 years.
- Age, diagnosis time, grade, and treatment were independent prognostic factors for hepatocellular carcinoma.

## Abstract

This study aimed to assess the difference in prognosis of patients with early-stage liver cancer after surgery or external radiation.

Between 2010 and 2015, 2155 patients with AJCC 7th stage I liver cancer were enrolled in the SEER database. Among these, 1972 patients had undergone surgery and 183 had undergone external beam radiation. The main research endpoints were overall survival (OS) and disease-specific survival (DSS). The competitive risk model was used to calculate the risk ratio of liver cancer-specific deaths when there was a competitive risk. Propensity Score Matching (PSM) method using a 1:1 ratio was used to match confounders such as sex, age, and treatment method. Conditional survival was dynamically assessed for patient survival after surgery or external radiation.

Multivariate analysis of the competitive risk model showed that age, disease diagnosis time, grade, and treatment [surgery and external beam radiation therapy (EBRT)] were independent prognostic factors for patients with hepatocellular carcinoma. Surgery had a higher survival improvement rate than that of EBRT. As the survival of patients with liver cancer increased, the survival curve of surgery declined more slowly than that of radiotherapy patients and stabilized around 3 years after surgery. The survival curve of radiotherapy patients significantly dropped within 4 years and then stabilized.

Surgery was better than EBRT for patients with stage I liver cancer. Close follow-up was required for 3 years after surgery or 4 years after external radiation. This study can help clinicians make better informed clinical decisions.