[Sensitivity study on preoperative individual concomitant radiochemotherapy for rectal cancer]

Area of Science:

• Oncology
• Gastroenterology
• Medical Research

Background:

• Local mid-low advanced rectal cancer requires effective preoperative treatment strategies.
• Preoperative concomitant radiochemotherapy is a standard approach, but predicting patient response remains a challenge.

Purpose of the Study:

• To identify predictive factors for sensitivity to preoperative concomitant radiochemotherapy in advanced rectal cancer.
• To guide individualized treatment selection for improved patient outcomes.

Main Methods:

• Retrospective analysis of 44 patients with advanced rectal cancer undergoing preoperative radiochemotherapy.
• Detection of epidermal growth factor receptor (EGFR) expression using immunohistochemistry.
• Assessment of treatment sensitivity via tumor downstaging and tumor regression grade (TRG).

Main Results:

• Patients with negative or weak positive EGFR expression showed significantly higher rates of tumor downstaging and TRG 3-4 compared to those with moderate or strong positive EGFR expression (P<0.01).
• Tubular adenocarcinoma histology was associated with significantly higher downstaging and TRG rates compared to mucous adenocarcinoma (P<0.01).
• EGFR expression and pathological type were independent of other clinicopathological factors analyzed (age, gender, TNM stage, CEA, CA199, radiation method).

Conclusions:

• Pathological type (tubular adenocarcinoma) and low EGFR expression are independent predictors of sensitivity to preoperative radiochemotherapy in rectal cancer.
• These markers can help personalize treatment strategies for patients with advanced rectal cancer.