Significant decrease of the pathological stage I rectal carcinoma in the era of neoadjuvant therapy-A matter of...

Area of Science:

• Oncology
• Surgical Oncology
• Gastroenterology

Background:

• Neoadjuvant treatment (nTx) for rectal cancer is standard for UICC stages II/III, but not for stage I (T1-2N0M0).
• Accurate clinical staging is crucial for appropriate treatment allocation, yet prone to understaging and overstaging.
• This study investigates changes in the proportion of early-stage (pI) rectal cancer patients following the introduction and increased use of nTx over 26 years.

Purpose of the Study:

• To analyze the trend in nTx application for rectal cancer over a 26-year period.
• To evaluate the impact of increasing nTx use on the proportion of early-stage (pI) rectal cancer patients.
• To assess the accuracy of clinical staging in patient selection for nTx.

Main Methods:

• A prospective database of consecutive rectal cancer patients (excluding carcinoma in situ) was utilized.
• Patients were categorized into three time periods based on nTx use: baseline (1994-1997), implementation (1998-2005), and guideline (2006-2019).
• Trends in nTx application and the proportion of stage pI tumors were analyzed over these periods.

Main Results:

• A total of 1468 patients were included, with stable characteristics including stage IV metastases over time.
• The application of nTx increased significantly from 1.2% in the baseline phase to 59.6% in the guideline phase (p < 0.001).
• Correspondingly, the proportion of stage pI rectal cancer patients decreased significantly from 31.0% to 14.2% (p < 0.001).

Conclusions:

• The increasing use of nTx correlated with a significant decrease in early-stage (pI) rectal cancer patients.
• This trend suggests potential overtreatment of rectal cancer due to inaccuracies in clinical T- and N-staging.
• More precise criteria are needed for selecting rectal cancer patients eligible for neoadjuvant treatment.