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 of age. 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.
It is well known that early detection of adenomas reduces the incidence of CRC and allows the diagnosis and treatment of cancer at an earlier stage. As CRC is increasing in young populations, it is important to know at which age the increase in incidence of colonic adenomas and advanced colonic adenomas occurs.
The purpose of this study was 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 in this observational monocentric study conducted in our unit by a team of 30 gastroenterologists.
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 in the 40-44 (n = 382) and 45-49 year old groups (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% in those aged 45-49 years (P < 0.001), and the ANDR increased from 3.1% in patients aged 40-44 to 6.4% in those aged 45-49 years (P < 0.03). In contrast, we did not observe a statistically significant increase in the ADR and ANDR between patients aged 45-49 and 50-54 years. When focusing on the population with an average risk for CRC, the ADR and ANDR were still significantly higher in patients aged 45 to 49 compared to patients aged 40 to 44 years.
This study showed a significant two-fold increase in the ADR and ANDR from 45 years of age, irrespective of a personal or family history of polyps or CRC.
This study raises questions regarding screening in patients less than 50 years of age. The medical benefit of performing colonoscopy as early as 45 years needs to be balanced by the medico-economic feasibility of such a screening policy. Nevertheless, whatever the screening method, the high ANDR observed in our young patients has to be taken into account in order to improve the prevention of CRC, disease stage on presentation and prognosis.