Majority of postcolonoscopy colorectal cancers preventable
Researchers have called for quality improvements in performance of colonoscopy after recent study data indicated procedure-related etiology for the majority of postcolonoscopy colorectal cancers, especially those in the proximal colon.
In a population-based multicenter study, the researchers identified 5,107 patients diagnosed with colorectal cancer (CRC) in South-Limburg, Netherlands, from January 2001 to December 2010 using colonoscopy and histopathology records from the Netherlands Cancer Registry. Postcolonoscopy colorectal cancer (PCCRC; n=147) was defined as CRC diagnosed within 5 years of an index colonoscopy.
CRC was categorized as either proximal or distal from the splenic flexure, and by macroscopic appearance as either protruded or flat. Etiology of PCCRC was defined as either procedural (inadequate examination or surveillance, incomplete resection or missed lesions) or biological (newly developed cancers detected at least 36 months after index colonoscopy).
Diagnoses averaged 26.1 months after index colonoscopy for PCCRC, and significantly more often than CRC their location was proximal (OR=3.92; 95% CI, 2.71-5.69), their size small (OR=0.78; 95% CI, 0.7-0.87) and their appearance flat (OR=1.7; 95% CI, 1.18-2.43). Procedural etiology accounted for 86.4% of all PCCRC, with 57.8% attributed to missed lesions, 19.8% to inadequate surveillance and 8.8% to incomplete resection. Of the PCCRC etiologically linked to missed lesions, 63% were located in the proximal colon, of which 57% were flat.
“The majority of PCCRC [86.4%] would most probably have been preventable,” the researchers wrote, “being caused by missed or incompletely removed lesions and inadequate examination or surveillance.”
The investigators concluded that proximal location, small size and flat appearance of most PCCRC is likely responsible for the missed and incompletely removed lesions in index colonoscopy.
“Systematic training of endoscopists, with a focus on detection and management of flat precursors, has the potential to prevent PCCRC,” they said.
Disclosure: The researchers report no relevant financial disclosures.