Colorectal Adenoma Containing Invasive Adenocarcinoma
Grading / Staging / Report
- It is acceptable to grade simply as Low vs. High grade
- Low grade ≥50% gland forming
- Well differentiated
- Moderately differentiated
- High grade <50% gland forming
- Poorly differentiated
- 5-49% gland forming
- Signet ring (>50% of cells signet ring)
- Undifferentiated
- Use TNM staging
- Lesions should be staged if the margins of resection are clear
- Provisional stage may be given if margins are involved but should be clearly indicated as provisional
- An adenoma containing only high grade dysplasia or intramucosal carcinoma is pTis
- An adenoma containing carcinoma invasive into the stalk is pT1 (unless it invades into muscularis propria)
