Diagnostic bias may explain increased CRC risk in Barrett’s esophagus patients
MedWire News: Study findings suggest that the increased risk for colorectal cancer (CRC) in patients with Barrett’s esophagus (BE) is most likely due to diagnostic bias rather than shared risk factors.
Some studies have reported an increased risk for CRC in BE patients compared with the general population, but many others have not. In addition, population-based studies investigating this association are scarce.
Using the Dutch nationwide histopathology registry, Pieter de Jonge (Erasmus MC–University Medical Center, Rotterdam, The Netherlands) and co-authors identified 42,207 patients with a first diagnosis of BE between 1991 and 2006.
Over a mean follow-up period of 5.6 years, 1.7% of BE patients were diagnosed with CRC, corresponding to an incidence of 3.4 per 1000 person-years. All CRCs occurred in patients aged older than 40 years, with the majority (96%) occurring in those over 50 years of age. In addition, 79% of cancers were found in the colon.
Overall, the relative risk for development of CRC in patients with BE was 1.7-fold higher than in the general Dutch population. The researchers also found that 44% of CRCs were detected within the first year of BE diagnosis.
The increased risk for CRC in patients with BE was therefore significantly higher in the first year of BE diagnosis than within 1-5 years and more than 5 years after diagnosis, at 4.76 versus 0.99 and 1.28, respectively.
However, after exclusion of the first year of follow-up after BE diagnosis, the risk for CRC was only modestly increased in comparison with the general population.
“These findings suggest that the overall increased risk for CRC in BE can be largely explained by diagnostic bias, ie, once having become a patient of a gastroenterology service, the chance of undergoing other gastroenterological procedures is considerably increased,” write the authors in the American Journal of Gastroenterology.
“The magnitude of the association between BE and CRC does not merit a more extensive CRC screening strategy in BE patients than has currently been recommended for the general population,” conclude de Jonge and team.
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By Ingrid Grasmo