Biopsy of gastrointestinal polyps removed endoscopically with resection margins

Biopsy of gastrointestinal polyps removed endoscopically with assessment of resection margins — is an in-depth pathomorphological study of the entire volume of the removed neoplasm (polypectomy). Unlike a conventional pinch biopsy, this study allows not only to determine the type of tumor, but also to answer the key surgical question: whether the neoplasm was completely removed within healthy tissues.

Research objective: The main task is microscopic control of the "cleanliness" of the edges of the cut. This is necessary to make sure that there are no tumor cells left at the base of the stem or along the edges of the flat polyp, which could cause a relapse or become a source of spread of the oncological process.

What does the pathologist evaluate:

• Histological type and structure: detailed analysis of the entire structure of the polyp (adenoma, serrated formation, etc.).

• Degree of cell dysplasia: determining the aggressiveness of changes (low grade or high grade).

• Status of resection margins (R0/R1): checking the cut line for the presence of tumor cells.

• Depth of invasion (if cancer is detected): assessment of how deep the tumor has grown into the submucosa (Kikuchi or Heggitt levels).

• Lymphovascular invasion: searching for tumor cells in the vessels surrounding the polyp.

Clinical significance: The pathologist's conclusion is crucial for the further strategy. If the resection margins are "clean" (negative), the patient is considered cured and only needs observation. If adenoma or cancer cells are found in the resection margin (positive margin), this is a direct indication for re-intervention or more radical surgery.

When is it prescribed:

• after endoscopic removal of polyps of the stomach, esophagus or intestine (polypectomy, EMR, ESD);

• when removing large formations on a wide basis;

• if early malignancy is suspected (malignant polyp);

• to determine follow-up tactics after complex endoscopic operations.