TOPLINE:
For individuals aged 45-49 years at average risk for colorectal cancer (CRC), the adenoma detection rate (ADR) in screening colonoscopies is 28%, which is comparable with rates seen in those aged 50-54 years.
METHODOLOGY:
- The rising incidence of CRC in younger populations prompted most guidelines to recommend screening to start at age 45. The impact of lowering the screening age on adenoma and sessile serrated lesion detection rates remains unclear, however.
- Researchers conducted a systematic review and meta-analysis of 16 studies; all studies were retrospective except one.
- Patients aged 45-49 years undergoing colonoscopy for any indication were included, with a separate analysis of patients in that age group at average CRC risk undergoing screening colonoscopies.
- The primary outcome was the overall detection rates of adenomas and sessile serrated lesions for colonoscopies performed for any indication.
TAKEAWAY:
- Across 15 studies, 41,709 adenomas were detected in 150,436 colonoscopies performed for any indication, resulting in a pooled overall ADR of 23.1%.
- Across six studies, 1162 sessile serrated lesions were reported in 11,457 colonoscopies performed for any indication, with a pooled detection rate of 6.3%.
- Across seven studies, the pooled ADR in screening colonoscopies performed on individuals with average CRC risk was 28.2%, which is comparable with that of 50- to 54-year-old individuals undergoing screening colonoscopy. There was not enough data to calculate the sessile serrated lesion detection rate in average-risk patients.
- The ADR was higher in the United States and Canada (26.1%) compared with studies from Asia (16.9%).
IN PRACTICE:
“The comparable detection rates of precancerous lesions in this age group to those 50 to 54 years old support starting CRC screening at 45 years of age,” the authors wrote.
SOURCE:
This study, led by Mohamed Abdallah, MD, Division of Gastroenterology and Hepatology, University of Minnesota Medical Center, Minneapolis, was published online in The American Journal of Gastroenterology.
LIMITATIONS:
The inclusion of retrospective studies has an inherent bias. The heterogeneity between studies may limit the generalizability of the findings. Some studies that reported detection rates included individuals at both average and high risk for CRC, so they could not be used to evaluate ADRs in individuals with an average risk for CRC. Data duplication could not be ruled out.
DISCLOSURES:
The study did not receive any funding. The authors declared no conflicts of interest.
A version of this article appeared on Medscape.com.