A Modified Tumor-Node-Metastasis Classification for Primary Operable Colorectal Cancer.

Area of Science:

• Oncology
• Cancer Staging
• Prognostic Biomarkers

Background:

• The American Joint Committee on Cancer (AJCC) 8th tumor-node-metastasis (TNM) classification for colorectal cancer (CRC) has limitations in predicting patient prognosis.
• Accurate prognostic prediction is crucial for tailoring treatment strategies and improving outcomes in CRC patients.

Purpose of the Study:

• To develop and validate a modified TNM (mTNM) classification for colorectal cancer (CRC) with improved prognostic discrimination.
• To compare the performance of the mTNM classification against the current AJCC 8th TNM classification.

Main Methods:

• Utilized a large cohort of 45,379 stage I-III CRC patients from the Surveillance, Epidemiology, and End Results (SEER) Program, divided into training, internal validation, and external validation sets.
• Employed Cox proportional hazard models, Kaplan-Meier analysis, and area under the receiver operating characteristic curve (AUC) for survival analysis and prognostic discrimination.
• Applied Akaike information criteria (AIC) for model fitting and decision curve analyses (DCAs) to assess clinical utility.

Main Results:

• The developed mTNM classification demonstrated superior prognostic discrimination (AUC = 0.675 vs. 0.667, P < .001) and better model fit (AIC = 70,937 vs. 71,238) compared to the AJCC 8th TNM system in both internal and external validation cohorts.
• The mTNM system showed improved net benefits in decision curve analyses, indicating greater clinical utility for stratifying CRC patients.

Conclusions:

• The modified TNM (mTNM) classification offers enhanced prognostic discrimination for stage I-III colorectal cancer (CRC) patients compared to the AJCC 8th TNM system.
• The mTNM classification demonstrates robust applicability across different populations and settings, facilitating more precise prognostic grouping of CRC patients.