# Effect of hyperthermic intraperitoneal chemotherapy on patients with advanced colorectal cancer: a systematic review and meta-analysis

## TL;DR

Hyperthermic intraperitoneal chemotherapy (HIPEC) may improve survival and reduce peritoneal metastases in advanced colorectal cancer, but it comes with increased risks of certain complications.

## Contribution

This study provides a systematic review and meta-analysis of HIPEC's effectiveness in advanced colorectal cancer, offering updated evidence on survival and recurrence outcomes.

## Key findings

- HIPEC improved 1-year disease-free survival and 5-year overall survival in advanced colorectal cancer patients.
- HIPEC reduced the overall peritoneal metastasis rate and showed preventive effects in high-risk cases without prior metastases.
- HIPEC increased the risk of thrombopenia and neutropenia as complications.

## Abstract

Advanced colorectal cancer (CRC) predisposes to peritoneal metastases (PM), leading to a decreased survival rate. Advanced CRC includes CRC with PM (CRC-PM) and locally advanced high-risk CRC without PM. The effectiveness of hyperthermic intraperitoneal chemotherapy (HIPEC) in prolonging survival and in treating or preventing PM after surgery for advanced CRC is still uncertain.

A search of PubMed, Cochrane, Embase, and Web of science databases for relevant studies prior to April 2024 was performed. Data were analyzed using Stata/MP 17.0 software. The primary outcomes included overall survival (OS) and disease-free survival (DFS). Secondary outcomes were overall recurrence rate (ORR), PM rate, and complications. The quality of evidence was assessed using Grading of Recommendations, Assessment, Development, and Evaluations (GRADE).

A total of ten high-quality cohort studies and four randomized controlled trials (RCTs) were included, encompassing 2851 patients. HIPEC improved 1-year DFS (odds ratio (OR) = 1.64, 95%Cl: 1.09–2.46) and 5-year OS (OR = 1.49, 95%Cl: 1.10–2.03) in advanced CRC. HIPEC also reduced the overall PM rate (OR = 0.66, 95%Cl: 0.49–0.90). For advanced high-risk CRC without prior PM, HIPEC reduced the PM rate and had a preventive effect (OR = 0.71, 95%Cl: 0.52–0.97). In terms of complications, HIPEC increased the incidence of thrombopenia (OR = 5.77, 95%Cl: 1.65–20.09) and neutropenia (OR = 3.21, 95%Cl: 1.74–5.90). The quality of evidence ranged from high to very low.

The use of HIPEC in treating advanced CRC may result in improved survival rates and a reduction in peritoneal recurrence or metastasis, although complications should be considered. Further investigation is required to clarify the role of HIPEC in more high-quality RCTs.

The online version contains supplementary material available at 10.1186/s12957-025-04165-7.