Malignant Colorectal Polyp Pathology: Are We Getting Sufficient Information to Make Decisions?

Area of Science:

• Colorectal cancer pathology
• Oncology reporting standards

Background:

• The College of American Pathologists provides guidelines for malignant colorectal polyp pathology reports, distinguishing "core" and "optional" histopathological elements.
• Incomplete reporting of these elements can lead to inaccurate tumor risk stratification.

Purpose of the Study:

• To assess the completeness of pathology reporting for core and optional histopathological elements in T1 colorectal cancers.
• To evaluate the impact of reporting completeness on risk stratification for malignant colorectal polyps.

Main Methods:

• A retrospective cohort study reviewed 431 pathology reports of endoscopically resected malignant colorectal polyps in Alberta, Canada (2014-2016).
• Histopathological elements were categorized as "core" or "optional" based on established guidelines.
• Malignant polyps were classified as high-risk or low-risk for lymph node metastases and local recurrence.

Main Results:

• Only 66.4% of reports included all three key elements: histological grade, deep margin, and lymphovascular invasion.
• Tumor budding, a significant factor for risk stratification, was reported in only 14.4% of cases.
• Addendum reports, issued for 8.3% of polyps, led to a change in risk stratification for 10 polyps (2.3%).

Conclusions:

• There is a high rate of incomplete reporting for essential histopathological elements in malignant colorectal polyp pathology reports in Alberta.
• Variables critical for surgical decision-making, such as tumor budding and depth of submucosal invasion, are often not reported as core elements.
• Pathology report review by a second pathologist frequently alters the risk stratification, highlighting the need for improved reporting consistency.