# MRI‐Derived Lymph Nodes Morphological and Topological Structure (LNs‐MTS) Model for Evaluating Immune Status and Prognosis in Rectal Cancer

## TL;DR

A new MRI-based model evaluates lymph node immune status in rectal cancer to improve prognosis and guide personalized treatment.

## Contribution

The LNs-MTS model uses MRI features to non-invasively assess immune status and risk in rectal cancer patients.

## Key findings

- Patients with large total LNs volume and distant drainage show strong immune infiltration and better survival.
- The LNs-MTS model outperforms current guidelines in risk stratification for rectal cancer.
- High-risk patients have stromal dominance and worse prognosis, while low-risk patients benefit from less aggressive treatment.

## Abstract

Tumor‐draining lymph nodes (LNs) immune status critically influences cancer progression and treatment response, yet reliable non‐invasive assessment remains clinically unavailable. To address this critical gap, an MRI‐derived LNs morphological and topological structure (LNs‐MTS) model is developed to evaluate the immune status of LNs in rectal cancer (RC). Integrating multicenter imaging, transcriptomic, and immunohistochemical data from 1,156 stage I‐II RC patients, enhanced immune activation in non‐metastatic LNs sized ≥0.5 cm and located ≥5 cm from the primary tumor is discovered. Then two quantitative MRI‐derived imaging features across 7,030 radiologically annotated LNs: total LNs volume (tLNV) and total LNs drainage distance (tLND) is developed, forming the basis of the LNs‐MTS model risk subtypes: high‐risk (HRS), moderate‐risk (MRS), and low‐risk (LRS). Patients in the LRS (characterized by large tLNV and distant tLND) show robust immune cell infiltration in the tumor microenvironment and excellent 5‐year survival, whereas HRS (characterized by small tLNV and near tLND) show stromal dominance and poorer prognosis. Clinically, LNs‐MTS offers a more precise and personalized risk assessment than current guideline‐based risk stratification, potentially sparing stage II‐LRS patients from unnecessary adjuvant treatment while identifying stage I‐HRS individuals for more aggressive treatment, providing valuable insights for personalized treatment strategies in RC management.

An MRI‐derived Lymph Nodes morphological and topological structure (LNs‐MTS) model is established to evaluate the immune status of the lymph node system in rectal cancer. It provides a non‐invasive, quantitative approach for prognosis assessment and optimizing adjuvant therapy decisions. This model addresses both over‐treatment and under‐treatment challenges in current practice.