Hello, my name is Tanya Kaltenbach, I'm an associate professor of clinical medicine at the University of California, San Francisco, and the VA San Francisco Medical Center. I will be speaking to you today about what should be in your polypectomy toolbox in 2020. So, first, why should we care about endoscopic resection, and that was brought to our attention about five years ago when, with the CARE study, it showed high incomplete resection rates being very common in both diminutive, small, and large polyps. That prompted us to look at competency of polypectomy among practicing gastroenterologists. We looked at 13 attending endoscopists at an academic center and showed that polypectomy competency varies significantly between colonoscopists, with 3 being a competent or 4 being a competent level, and the mean of the 13 attending endoscopist competency level was 2.8. This low rate of competency was shown both for diminutive polyps and small and large polyps. This low rate of competent polypectomy was across sizes of polyps, prompting us to visit the training of polypectomy and the techniques of polypectomy. The learning objectives of our talk today will be to optimize removal of colorectal lesions to prevent cancer incidence and the need for surgery, doing this through understanding the mindset, describing the techniques, identifying the tools, and summarizing the U.S. Multicellular Task Force Polypectomy document. This document was published in March by the three societies. Let us first start with the endoscopic resection tools. I practice at both a government hospital and academic center and have had experience in a community hospital, and my polypectomy practices at these places are similar. I essentially have this list of tools on a dedicated cart and can approach polypectomy in a streamlined way. I'll review some of the tools more specifically in the following slides. First in our document, we recommend the use of carbon dioxide insufflation instead of air during colonoscopy and EMR. This is a strong recommendation with moderate quality evidence. All units should have a carbon dioxide insufflator as their standard gas. We also highlighted the use of cautery and suggested the use of microprocessor-controlled electrosurgical units. This was a conditional recommendation based on very low-quality evidence. The microprocessor-controlled electrosurgical units allow for controlled delivery of both cutting and coagulation current. This can minimize burn as we apply endoscopic resection to a variety of lesions. We also highlight in the document the use of injection solution, and we suggest the use of a viscous injection solution for lesions 20 millimeters or larger to remove the lesion in fewer pieces and less procedure time compared to normal saline. And we also recommend a stiff snare. A stiff snare is useful both for cold snare polypectomy as well as endoscopic mucosal resection. Here are some examples. There are many stiff snares available on the market. And the use of a cap is great for your toolbox with endoscopic resection. In some cases, endoscopic resection of a lesion may require an ESD knife, and this is good to have in your tools. But my polypectomy toolbox in 2020 is not just the tools, but it also includes my mindset, the unit's mindset, the technique, and the tools. So let's review some of these important aspects to a toolbox. The mindset. We want to have a mindset of complete, safe, and efficient curative removal in a single session. We want our team to be organized and synchronized, and we want our team to engage in quality assurance programs. When our mindset is with these parameters, we then apply a technique in a very systematic way. We interpret the lesion irrespective of its size. We then, through interpreting the polyps, can then decide on the appropriate management to resect it safely, completely, and efficiently. We do this in a way that we prevent complication, and if a complication occurs, we can manage it. And following removal, we interpret the pathology in order to follow the patient appropriately. And again, the tools, as I showed in the previous slides, we have system-wide unit tools of carbon dioxide, a water jet pump, a microprocessor carter unit, an endoscope, and standard accessories, including the stiff snares, the viscous injection solution, caps, clips, loops, and chromoendoscopy. And we also want to use a tool to gauge our endoscopic skills at polypectomy, and there are competency assessment tools available for cold snare polypectomy, for polypectomy that we can use to improve our technique. In our multi-society task force document, we made an algorithm on the endoscopic management of superficial colorectal lesions. I'm going to highlight a few of these examples and the tools and approaches that can be used. First, for any of them, we want to classify the lesion and its morphology using the PARIS classification. We want to classify non-polyploid lesions over a centimeter further into lateral spreading lesions. This helps us determine what tools we will use. And we want to apply the NICE classification as an optical diagnosis tool to, again, help us interpret the lesion histology, and then determine the best treatment strategy. And through that, determine the best tools necessary. And we want to identify the endoscopically unrespectable lesions, the features of deep submucosal invasions, such as redness, firm consistency, expansion, fold convergence, deep depressed areas. Our tools change in this, and we certainly need this in our polypectomy toolbox. In these cases, we need a biopsy and we need a tattoo. So for diminutive lesions, for example, a snare is our best tool. Why is that? We can see here that a biopsy for even a diminutive lesion will not allow for unblocker section. You can see there is polyp tissue left behind. As opposed to approaching this lesion using optical diagnosis, this is a NICE type 2 adenoma with high confidence. Positioning this in the 6 o'clock position. And then using a stiff snare, we can anchor the tip of the snare in the proximal side of the polyp and grab normal tissue around it and resect it unblocked very efficiently and confidently. In contrast to the biopsy on biopsy of that diminutive polyp shown in the previous video. Here's a figure showing the steps of cold snare polypectomy and the tool used. You can appreciate the stiffness of the snare and how it allows you to anchor it, push down, resect at the submucosal there and get normal tissue around it. The rate of confident polypectomy for cold forceps versus snare polypectomy is very clear that cold snare and hot snare polypectomy achieves competency rates of polypectomy much higher than cold forceps. We have developed a coltisnare polypectomy assessment tool that you can use and apply in your practice. These tools have different domains of the various steps within the technique. For EMR of flat or serrated lesions of 10 millimeters or larger, endoscopic mucosal resection is a technique of choice. And the technique has been described. We want to optimize the position at six o'clock, use the dynamic submucosal injection, unblock resection when possible, use a stiff snare with a healthy margin, target the advanced pathology, use insufflation and desufflation, have a tight snare closure, transect fast and assess the close resection margin. Here's an example of that technique using an injection needle. I'm going to inject. Here, you can see that the saline has indigo carmine as a contrast. Using dynamic injection, creating a mold and a blub to transform the non-polyploid lesion into a polyploid shape that then a snare can easily grasp. And in this case, allowing for an unblock resection of this serrated lesion. So you can, again, appreciate the stiffness of the snare. Very important tool is your snare choice, both the stiffness and the size of the snare. A slow closure to grasp normal around the lesion, a tight closure, and then a fast transection using that microprocessor cautery unit. And with that cutting current delivery, you can see minimal burn. For pedunculated lesions, one of the tools that's important is the nylon, detachable nylon loop. And we recommended this in the task force document on polyps that were two centimeters or larger in the head or five millimeter or wider for the stalk. And you can see here in this that the reason that the task force recommended this was based on various trials that showed a decreased risk of bleeding with loop or clipping of the stalk. So we recommended mechanical ligation of the stalk with a prophylactic detachable loop or a clip on pedunculated lesions with a head 20 millimeter or larger or with a stalk thickness five millimeter or larger to reduce immediate and delayed post-polypectomy bleeding. And here is an example of that. You can see the large, wide stalk with the large head. A nylon loop is being maneuvered over the head of the polyp, along the stalk to the base of the stalk, tightened it, and you get a ligature that then the feeding vessel is ligated. The polyp becomes ischemic. You can see the purple pale hue of the polyp. And then you would transect the polyp above the loop using a snare, leaving the loop behind to prevent delayed bleeding. Sometimes we do need to use ESD or hybrid ESD for non-lifting lesions or IBD-associated dysplasia. And in this case, having a ESD knife in your toolbox is important. Here's an example where the polyp morphology was concerning with that central nodule. So an unblocked resection was important here. And in this case, snare resection would probably not allow for that. And so isolating the lesion using an ESD knife with circumferential incision around the polyp. You can appreciate the non-lifting. So here is an example where ESD is necessary. There is a polyp where the morphology with the central nodule is concerning. An unblocked resection is important for at least the pathologic staging. So in this case, an ESD knife is a useful tool to allow for submucosal access. So circumferential incision following injection, you can appreciate the non-lifting area, that central depression. It's gonna be difficult to capture with a snare. So in this case, following injection, doing a circumferential incision to then allow snare access to the submucosa. for an unblocked resection was really key here. So again, my intent and my mindset was for a complete, safe, and efficient unblocked resection that's allowed for definitive pathologic staging and curative resection of this lesion that had pseudo-invasion. So in summary, endoscopic resection of colorectal lesions has been shown to be safe and effective. However, incomplete polyp resection rates are high. The majority of surgically treated benign polyps are about two centimeters, and this is despite surgical morbidity of about 14%, mortality of about 1%, and cost being five times higher than endoscopic resection. We should focus on optimal, complete polyp resection techniques such as cold-snare polypectomy for small polyps and inject and cut endoscopic mucosal resection for large and serrated lesions. And we should target education and training so that we can improve the quality of colonoscopy. Thank you.

endoscopic resection tools

polypectomy

carbon dioxide insufflation

microprocessor-controlled electrosurgical units

colorectal lesions