Association Between Mesorectal Grade and Oncologic Outcomes in Rectal Cancer: A Systematic Review and Meta-Analysis.

Area of Science:

• Colorectal Surgery
• Oncology
• Surgical Pathology

Background:

• Total mesorectal excision (TME) is a cornerstone of rectal cancer surgery.
• The quality of TME, specifically its completeness, may significantly influence patient outcomes.
• Standardized grading systems for TME quality are essential for consistent surgical practice.

Purpose of the Study:

• To evaluate the impact of TME grading on local recurrence, distant metastasis, and overall survival in rectal cancer patients.
• To compare outcomes between complete/near-complete TME and incomplete TME.
• To synthesize existing evidence through a meta-analysis.

Main Methods:

• Systematic literature search of PubMed and Scopus databases.
• Inclusion of ten studies published between 2002 and 2023.
• Meta-analysis of outcomes including local recurrence, distant recurrence, and overall survival.

Main Results:

• Incomplete TME was associated with significantly lower overall survival (HR 0.75, p=0.044).
• Patients with incomplete TME had higher rates of local recurrence (RR 3.09, p=0.001) and distant recurrence (RR 1.44, p=0.005).
• Complete and near-complete TME demonstrated similar risk profiles for recurrence and survival.

Conclusions:

• This meta-analysis confirms the critical role of complete TME in achieving favorable outcomes for rectal cancer.
• Incomplete TME is a significant risk factor for recurrence and reduced survival.
• Adherence to complete TME principles is crucial for optimizing rectal cancer treatment and patient prognosis.