Published online Jan 28, 2019. doi: 10.3748/wjg.v25.i4.447
Peer-review started: November 12, 2018
First decision: December 20, 2018
Revised: December 23, 2018
Accepted: December 27, 2018
Article in press: December 28, 2018
Published online: January 28, 2019
Processing time: 79 Days and 13.7 Hours
Colonoscopy is considered a valid primary screening tool for colorectal cancer (CRC). The decreasing risk of CRC observed in patients undergoing colonoscopy is correlated with the adenoma detection rate (ADR). Due to the fact that screening programs usually start from the age of 50, very few data are available on the risk of adenoma between 40 and 49 years. However, the incidence of CRC is increasing in young populations and it is not uncommon in routine practice to detect adenomas or even advanced neoplasia during colonoscopy in patients under 50 years.
To compare the ADR and advanced neoplasia detection rate (ANDR) according to age in a large series of patients during routine colonoscopy.
All consecutive patients who were scheduled for colonoscopy were included. Exclusion criteria were as follows: patients scheduled for partial colonoscopy or interventional colonoscopy (for stent insertion or stenosis dilation). Colonoscopies were performed in our unit by a team of 30 gastroenterologists in 2016. We determined the ADR and ANDR in each age group in the whole population and in the population with an average risk of CRC (excluding patients with personal or family history of advanced adenoma or cancer).
6027 colonoscopies were performed in patients with a median age of 57 years (range, 15-96). The ADR and ANDR were 28.6% and 9.7%, respectively, in the whole population. When comparing patients aged 40-44 (n = 382) and 45-49 years (n = 515), a strong increase in all parameters from 45 years was observed, with the ADR rising from 9.7% in patients aged 40-44 to 21.2% between 45 and 49 (P < 0.001) and the ANDR increasing from 3.1% in patients aged 40-44 to 6.4% in those aged 45-49 years (P < 0.03). With regard to patients aged 50-54 (n = 849), a statistically significant increase in the ADR and ANDR was not observed between patients aged 45-49 and those aged 50-54 years. In the population with an average risk of CRC, the ADR and ANDR were still significantly higher in patients aged 45-49 compared with those aged 40-44 years.
This study shows a significant two-fold increase in the ADR and ANDR in patients aged 45 years and over.
Core tip: Despite the fact that the incidence of colorectal cancer (CRC) in individuals less than 50 years seems to have increased in the last decade, there are very few data on adenoma and advanced neoplasia in this age group. This is the first large study to evaluate the adenoma detection rate (ADR) and advanced neoplasia detection rate (ANDR) in patients under 50 years during routine colonoscopy in average-risk and high-risk CRC patients. This study showed a significant two-fold increase in the ADR and ANDR in patients aged 45 years and older, irrespective of a personal or family history of polyps or cancer. Such high rates in those aged 45 years and over should be taken into account in CRC screening campaigns.