# Outcome of Patients with Locally Advanced Rectal Cancer Pursuing Non-Surgical Strategy in National Cancer Database

## TL;DR

Patients with advanced rectal cancer who avoid surgery have worse survival outcomes compared to those who undergo surgery, especially those with high-risk tumors.

## Contribution

This study provides real-world evidence on survival outcomes of non-surgical treatment for locally advanced rectal cancer.

## Key findings

- Non-operative management resulted in significantly lower 5-year survival rates compared to surgery in both cT1-3N+ and cT4N+/− patients.
- Patients with T4 tumors had particularly worse survival outcomes with non-surgical treatment.
- Propensity score matching and multivariable analyses confirmed the inferior survival with non-operative management.

## Abstract

The current study examined the outcomes of patients with locally advanced rectal cancer (LARC) who underwent non-operative management (NOM) instead of surgery in routine clinical practice. Using data from the National Cancer Database, we found that those who did not undergo surgery had lower survival rates than those who had surgical interventions. Specifically, patients with high-risk features, for example, patients with T4 tumors, had much more inferior survival with NOM than with surgery. These findings suggest that opting for NOM might result in worse survival outcomes, underscoring the need for further research to confirm these results.

Background: Survival data on patients with locally advanced rectal cancer (LARC) undergoing non-operative management (NOM) in a real-world setting are lacking. Methods: We analyzed LARC patients from the National Cancer Database with the following features: treated between 2010 and 2020, age 18–65 years, Charlson comorbidity index (CCI) ≤ 1, received neoadjuvant multiagent chemotherapy plus radiation ≥ 45 Gray, and underwent surgery or NOM. Patients were stratified into two groups: (A) clinical T1-3 tumors with positive nodes (cT1-3N+) and (B) clinical T4 tumors, N+/− (cT4N+/−). We performed a comparative analysis of overall survival (OS) with NOM versus surgery by the Kaplan–Meier method and propensity score matching. Additionally, a multivariable analysis explored the association between NOM and OS. Results: NOM exhibited significantly lower OS than surgery in both groups. In cT1-3N+ patients, NOM resulted in a 5-year OS of 73.9% (95% confidence interval [CI] = 69.7–77.6%) versus 84.5% (95% CI = 83.6–85.3%) with surgery (p < 0.001). In the cT4N+/− group, NOM yielded a 5-year OS of 44.5% (95% CI = 37.0–51.8%) versus 72.5% (95% CI = 69.9–74.8%) with surgery (p < 0.001). Propensity score matching and multivariable analyses revealed similar conclusions. Conclusion: Patients with LARC undergoing NOM versus surgery in real-world settings appear to have inferior survival.