Endoscopists are often faced with unique challenges in the management and resection of various gastrointestinal tract lesions. These challenges could be lesion-related, endoscopist-related, or practice-related (see Table 1). (ATR). Not only does this organ-sparing approach offer a less invasive alternative to surgery, but it has also proved to have outcomes comparable to those of surgical standard of practice in specific scenarios.
When Do You Refer to an Advanced Endoscopist?
One of the most critical steps in caring for patients with complex lesions is the ability to accurately determine whether a referral to an advanced endoscopist is warranted. The initial assessment of a lesion should always involve a careful assessment that risk stratifies the lesion depending on the location, size, neoplastic potential, and the feasibility of standard endoscopic resection compared to the need for surgical input.
A practical example in the case of colonic polyps is highlighted by the American Gastroenterology Association (AGA) guidelines recommending the referral of patients with polyps’ size ≥ 20 mm, challenging polypectomy location, or recurrent polyp at a prior polypectomy site to an endoscopic referral center.1 In the case of subepithelial lesions without endoscopic characteristics of benign etiology (i.e., lipomas, pancreatic rests, etc.), the threshold for referral to advanced endoscopists for further diagnostic testing by means of endoscopic ultrasonography or for therapeutic ATR should be lower.
Endoscopic tissue resection follows a spectrum, which often involves deeper layers of the gastrointestinal tract (GIT) as we progress along this spectrum (see Figure 1).
Dr. Madi; Dr. Rengarajan, and Dr. Bazarbashi
Figure 1: Spectrum of Tissue Resection
ATR, a term encompassing a variety of endoscopic techniques ranging from endoscopic mucosal resection to full thickness resection, has gained traction over the last years given the ability to effectively remove various lesions in a precise time and cost-effective manner while maintaining the integrity of the GIT and avoiding major surgery. The indications for ATR vary depending on the technique, but generally include the presence of large or poorly positioned lesions, particularly in high-risk areas of the GIT such as the esophagus and small intestine, lesions extending beyond the mucosal layer or originating from deeper layers, and when en bloc resection of select lesions is necessary.
Saint Louis University School of Medicine
Dr. Mahmoud Y. Madi
For providers referring patients for ATR, we recommend a few important endoscopic pearls when caring for these patients.
1) Biopsy the lesion if there is concern for malignancy — While some studies have noted increased fibrosis during endoscopic submucosal dissection (ESD) and some guidelines recommend against biopsies pre ESD, we believe that when there is high pretest probability for malignancy, a biopsy should be obtained. This should involve the area that is most concerning for malignancy (at the margin or center).2
2) While marking a lesion with tattoo is helpful for surgical planning and for lesions difficult to locate endoscopically, we stress the importance of placing tattoos 3 to 5 centimeters distal to the lesion and avoiding tattooing the lesion itself, which has been shown to induce fibrosis and can make resection challenging. Based on an international Delphi consensus, expert recommendations on when and how to endoscopically tattoo a lesion can be instrumental in adequately localizing the lesion, allowing for endoscopic resection, and preventing unnecessary surgeries.3
3) If you encounter a lesion that you are not sure can be resected safely and efficaciously, we recommend against attempting resection that may result in partial resection. This can also induce fibrosis and scarring and limit future attempts at resection.
