Methods for assessing completeness of colorectal polyp resections: a comprehensive review and first steps towards a standardized clinical protocol

Aims Incomplete resection of neoplastic colorectal polyps is associated with polyp recurrence and is estimated to be the root cause of 7-19% of post-colonoscopy colorectal cancers [1] [2]. However, a standardized method for assessment of completeness of polyp resections is lacking. This results in the use of different reference standards, impacting complete resection rates as reported in different studies and hampering robust comparisons between different resection tools, techniques, individuals and institutions [3]. Aiming to establish a standardized protocol, an overview of currently used methods is required. We conducted a comprehensive review of methods for assessment of completeness of polypectomy and the variability in how these methods are used.

Methods A comprehensive scoping review was performed by two independent authors within MEDLINE, Embase, Web of Science and Cochrane Library databases, covering publications from their inception up to July 30, 2024. Studies describing the use or validation of methods for assessment of completeness of polypectomy, specifically at the time of polyp resection, were included. Studies using recurrence of neoplasia at follow-up colonoscopies were excluded. Moreover, studies using histopathological assessment of resection margins were included only if these were used as a validation method for completeness of polypectomy. Strengths and limitations of identified methods were evaluated.

Results Of 4.697 records, 49 were included. Most studies were from Asia (42%), followed by Northern-America (29%), Europe (21%) and Australia (8%). Twenty-nine studies (7.285 patients) described biopsy-aided assessment of completeness of polypectomy. Biopsy protocols within these studies varied in terms of biopsy location (margins, base, or both) and number (one to eight) of biopsies and whether or not different protocols, both in terms of location and number of biopsies, were used for polyps of various sizes. In another eight studies (640 patients) extended resection of normal appearing mucosa around polypectomy sites was performed. Protocols used within these eight studies especially differed in terms of the extent of additional resection margins (1-3 mm margins). Six studies (1.494 patients) evaluated the use of image enhancement techniques to optimize completeness of resection and demonstrated that, compared to white light endoscopy, image enhancement techniques improved detection of remnant polyp tissue and percentage of complete resections in almost all studies. Other identified methods included endoscopic ultrasonography (n=4, 172 patients), assessment using artificial intelligence (n=1, 10 patients) and use of the size of the mucosal defect as proxy for completeness of resection (n=1, 210 patients).

Conclusions This review highlights the variability in methods used to assess the completeness of polyp resections and underscores the need for a standardized protocol. Findings of this review will serve as a starting point for an expert-consensus initiative to establish a protocol for this relevant quality parameter.

Publication History

Article published online:
27 March 2025

• References

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