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Published on: May 10, 2021
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Circumferential resection margin as a prognostic factor after rectal cancer surgery: A large population-based
Qi Liu1,2, Dakui Luo1,2, Sanjun Cai1,2
1Department of Colorectal Surgery, Fudan University Shanghai Cancer Center, Shanghai, China.
Cancer Medicine
|July 12, 2018
Summary
Circumferential resection margin (CRM) less than or equal to 1 mm significantly increases rectal cancer mortality risk. Maximizing CRM is crucial for better oncologic survival, with close attention for patients with CRM ≤1 mm.
Area of Science:
- Oncology
- Surgical Pathology
Background:
- Rectal cancer prognosis is influenced by surgical outcomes.
- Circumferential resection margin (CRM) status is a key factor in rectal cancer surgery.
- Accurate CRM measurement is vital for predicting patient survival.
Purpose of the Study:
- To investigate the prognostic significance of CRM for long-term oncologic survival in rectal cancer patients.
- To establish the relationship between CRM size and cancer-specific survival (CSS).
Main Methods:
- Retrospective analysis of rectal cancer patients from the SEER program (2010-2014).
- Patients categorized into five CRM groups (0-1 mm, 1.1-2.0 mm, 2.1-5.0 mm, 5.1-10.0 mm, >10 mm).
- Comparison of baseline characteristics and assessment of CSS across CRM groups.
Main Results:
- A CRM of ≤1 mm was independently associated with a 99% increased risk of cancer-specific mortality (HR=1.990).
- A CRM of 5.1-10.0 mm showed a trend towards decreased mortality risk (HR=0.708), though not statistically significant.
- CRM thresholds of ≤2 mm or ≤0.4 mm did not show a clear association with CSS.
Conclusions:
- CRM is an independent prognostic factor in rectal cancer.
- Surgeons should aim to maximize CRM during rectal cancer surgery.
- Rectal cancer patients with CRM ≤1 mm require heightened postoperative monitoring and precise CRM measurement in reports.
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