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Risk Calculator for Metachronous Advanced Neoplasia After Colorectal Polypectomy

Patient Characteristics at time of Colonoscopy with Polypectomy

Colonoscopist Information

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* The no adenoma group included patients with no adenoma, as well as patients with only a sessile serrated lesion.
**ADR is defined as the proportion of colonoscopic examinations performed by a physician that detected one or more adenomas.


post polypectomy risk stratification calculator


  • This model was developed as part of a retrospective cohort study of individuals with baseline polypectomy and subsequent surveillance colonoscopy 2004-2016 within the US Department of Veterans Affairs (VA). Clinical factors, polyp findings, and baseline colonoscopist adenoma detection rate (ADR) were considered for the model. Model performance [sensitivity, specificity, and area under curve (AUC)] for identifying individuals with metachronous advanced neoplasia was compared to 2020 US Multi-Society Task Force on Colorectal Cancer (USMSTF) surveillance recommendations. 30,897 individuals were randomly assigned 2:1 into independent model training and validation sets. Increasing age, male gender, diabetes, current smoking, adenoma number, polyp location, adenoma >10 mm or with tubulovillous/villous features, and decreasing colonoscopist ADR were independently associated with metachronous advanced neoplasia. A range of 1.48 to 1.66-fold increased risk for metachronous advanced neoplasia was observed for ADR in the lowest three quintiles (ADR <19.7 to 39.3%) vs. the highest quintile (ADR >47.0%). When the final model selected based on the training set was applied to the validation set, improved sensitivity and specificity over 2020 USMSTF risk stratification were achieved (p<0.001), with an AUC of 0.62 (95% CI: 0.60, 0.64). The calculator above utilizes the variables included in this model. Of note, as of October 2022, the model has not been externally validated in a non-VA cohort. The full report of the study including model development methods is available upon request.

  • Metachronous advanced neoplasia is defined by the presence of any of the following: colorectal cancer; adenoma 10 mm or larger in size; adenoma with high-grade dysplasia; adenoma with tubulovillous or villous histology.

  • Reference for the development and validation of the model is our recently published paper titled "Adenoma Detection Rate and Clinical Characteristics Influence Advanced Neoplasia Risk after Colorectal Polypectomy" (Gupta, PI).


  • Samir Gupta, MD, MSCS, AGAF
  • Lin Liu, PhD
  • Ashley Earles, MPH, PMP
  • Alexander Duan, BA

Contact Information

Samir Gupta, MD, MSCS, AGAF