Samsung Medical Center Cancer Center Proposes New Criteria for Early-Stage Colorectal Cancer Surgery

Development of a “Composite Pathological Score” Reflecting Five Key Risk Factors
Published in the Journal of the American College of Surgeons
“If Risk Is Low, Close Monitoring Is More Beneficial for Patients”

A team of domestic researchers has developed new criteria to identify which patients with early-stage colorectal cancer require additional surgery after endoscopic resection.

Samsung Medical Center announced on May 14 that a research team led by Professors Kim Heecheol and Shin Jeongkyung analyzed 1,162 patients who underwent additional surgery following endoscopic resection for early-stage colorectal cancer (T1) at Samsung Medical Center between 2004 and 2024. Based on this analysis, they have established new criteria to more accurately identify which patients truly need surgery. The research findings were recently published in the latest issue of the Journal of the American College of Surgeons.

For early-stage colorectal cancer, it is generally standard practice to monitor the patient after removing the tumor via endoscopy. However, if risk factors such as lymphatic, vascular, or neural invasion, tumor budding, poor differentiation, or deep submucosal invasion are identified after the procedure, current guidelines recommend additional surgery. This is to ensure the complete removal of any remaining cancer cells in the lymph nodes or other tissues.

However, these guidelines have long been criticized as being overly broad. Reports have shown that 80-90% of patients who underwent additional surgery after endoscopic resection did not have lymph node metastasis. As a result, there is significant criticism that many early-stage colorectal cancer patients are subjected to unnecessary surgical burdens.

Through their analysis, the research team found lymph node metastasis in 148 patients (12.7%) out of the total. Based on these findings, they developed what they call the "Composite Pathological Score."

The Composite Pathological Score evaluates five criteria following endoscopic resection for early-stage colorectal cancer: (1) presence of lymphatic, vascular, or perineural invasion; (2) tumor budding of five or more; (3) degree of differentiation; (4) submucosal invasion of 2,000 micrometers (μm) or more; and (5) presence of cancer cells at the resected specimen’s surface. Each criterion is given one point if applicable, for a total possible score of five.

The research team classified patients with a score of two or higher as a high-risk group, and those with a score of zero or one as a low-risk group. The higher the score, the steeper the rate of lymph node metastasis: 6.6% for 0 points, 12% for 1 point, 29.2% for 2 points, 60% for 3 points, and 100% for 4 points. The overall lymph node metastasis rate was 9.5% in the low-risk group and 33.5% in the high-risk group, showing a clear difference between the two.

Based on these results, the research team emphasized that for patients in the low-risk group with a Composite Pathological Score of zero or one, the decision to perform additional surgery should be made with greater caution. In particular, for elderly patients or those with comorbidities that make surgery riskier, opting for close monitoring rather than aggressive surgery would be more beneficial for the patient.

Kim Heecheol, Director of the Cancer Center at Samsung Medical Center, stated, "Even for cancer patients, it is only natural to identify and treat those who truly require surgery," adding, "We will continue to develop more sophisticated and precise surgical criteria so that patients’ quality of life and autonomy can be better respected."

This content was produced with the assistance of AI translation services.