Prediction model of the risk for lateral local recurrence in locally advanced rectal cancer without enlarged lateral...

Area of Science:

• Oncology
• Surgical Oncology
• Rectal Cancer Research

Background:

• The benefit of lateral lymph node dissection (LLND) for enlarged lateral lymph nodes in rectal cancer is accepted.
• However, its value for patients without enlarged lateral lymph nodes remains uncertain.
• Locally advanced rectal cancer (LARC) requires precise treatment strategies to minimize recurrence.

Purpose of the Study:

• To develop a prediction model for future lateral local recurrence (LLR) risk in LARC patients.
• To evaluate the oncological value of adding LLND in LARC patients without enlarged lateral lymph nodes.
• To identify factors influencing LLR to guide selective surgical decisions.

Main Methods:

• Retrospective, multi-institutional study of 812 patients with cStage II/III low rectal cancer.
• Exclusion criteria included enlarged lateral lymph nodes (≥7 mm).
• Analysis focused on predicting total lateral local recurrence (TLLR) and the impact of LLND.

Main Results:

• The overall TLLR rate was 8.3% (67 patients).
• Key risk factors for TLLR included no preoperative chemoradiotherapy (OR: 33.2), tumor distance ≤40 mm (OR: 2.71), and lateral lymph nodes measuring 5-7 mm (OR: 2.38).
• In patients with 5-7 mm lateral lymph nodes, LLND reduced recurrence from 21.6% to 8.0% in those not receiving preoperative treatment.

Conclusions:

• A novel prediction model for LLR risk was developed.
• This model can aid in selectively indicating LLND based on patient-specific risk stratification.
• Selective LLND may optimize treatment and reduce recurrence in rectal cancer patients.