The U.S. Multi-Society Task Force (USMSTF) on Colorectal Cancer recently published recommendations for endoscopic removal of precancerous colorectal lesions.
According to lead author Tonya Kaltenbach, MD, of the University of California, San Francisco, and fellow panelists, the publication aims to improve complete resection rates, which can vary widely between endoscopists; almost one out of four lesions (22.7%) may be incompletely removed by some practitioners, leading to higher rates of colorectal cancer.
“[A]lthough the majority (50%) of postcolonoscopy colon cancers [are] likely due to missed lesions, close to one-fifth of incident cancers [are] related to incomplete resection,” the panelists wrote in Gastroenterology, referring to a pooled analysis of eight surveillance studies.
The panelists’ recommendations, which were based on both evidence and clinical experience, range from specific polyp removal techniques to guidance for institution-wide quality assurance of polypectomies. Each statement is described by both strength of recommendation and level of evidence, the latter of which was determined by Grading of Recommendations, Assessment, Development, and Evaluation Ratings of Evidence (GRADE) criteria. Recommendations were written by a panel of nine experts and approved by the governing boards of the three societies they represented – the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. The recommendations were copublished in the March issues of the American Journal of Gastroenterology, Gastroenterology, and Gastrointestinal Endoscopy.
Central to the publication are recommended polypectomy techniques for specific types of lesions.
“Polypectomy techniques vary widely in clinical practice,” the panelists wrote. “They are often driven by physician preference based on how they were taught and on trial and error, due to the lack of standardized training and the paucity of published evidence. In the past decade, evidence has evolved on the superiority of specific methods.”
“Optimal techniques encompass effectiveness, safety, and efficiency,” they wrote. “Colorectal lesion characteristics, including location, size, morphology, and histology, influence the optimal removal method.”
For lesions up to 9 mm, the panelists recommended cold snare polypectomy “due to high complete resection rates and safety profile.” In contrast, they recommended against both cold and hot biopsy forceps, which have been associated with higher rates of incomplete resection. Furthermore, they cautioned that hot biopsy forceps may increase risks of complications and produce inadequate tissue samples for histopathology.
For nonpedunculated lesions between 10 and 19 mm, guidance is minimal. The panelists recommended cold or hot snare polypectomy, although this statement was conditional and based on low-quality evidence.
Recommendations were more extensive for large nonpedunculated lesions (at least 20 mm). For such lesions, the panelists strongly recommended endoscopic mucosal resection (EMR). They emphasized that large lesions should be removed in the fewest possible pieces by an appropriately experienced endoscopist during a single colonoscopy session. The panelists recommended the use of a viscous injection solution with a contrast agent and adjuvant thermal ablation of the post-EMR margin. They recommended against the use of tattoo as a submucosal injection solution, and ablation of residual lesion tissue that is endoscopically visible. Additional recommendations for large lesions, including prophylactic closure of resection defects and coagulation techniques, were based on low-quality evidence.
For pedunculated lesions greater than 10 mm, the panelists recommended hot snare polypectomy. For pedunculated lesions with a head greater than 20 mm or a stalk thickness greater than 5 mm, they recommended prophylactic mechanical ligation.
Beyond lesion assessment and removal, recommendations addressed lesion marking, equipment, surveillance, and quality of polypectomy.
Concerning quality, the panelists recommended that endoscopists participate in a quality assurance program that documents adverse events, and that institutions use standardized polypectomy competency assessments, such as Cold Snare Polypectomy Competency Assessment Tool and/or Direct Observation of Polypectomy Skills.
“Focused teaching is needed to ensure the optimal endoscopic management of colorectal lesions,” the panelists wrote. They went on to suggest that “development and implementation of polypectomy quality metrics may be necessary to optimize practice and outcomes.”
“For example, the type of resection method used for the colorectal lesion removal in the procedure report should be documented, and the inclusion of adequate resection technique as a quality indicator in colorectal cancer screening programs should be considered,” they wrote. “Adverse events, including bleeding, perforation, hospital admissions, and the number of benign colorectal lesions referred for surgical management, should be measured and reported. Finally, standards for pathology preparation and reporting of lesions suspicious for submucosal invasion should be in place to provide accurate staging and management.”
The investigators reported relationships with Covidien, Ironwood, Medtronic, and others.
SOURCE: Kaltenbach T et al. Gastroenterology. 2020 Jan 18. doi: 10.1053/j.gastro.2019.12.018.
