Table 2.

Reasons in favor of and against colorectal cancer screening from 45 years of age

Reasons favoring earlier screening	Reasons against earlier screening
Burden of disease
The incidence of eoCRC is increasing, and metastatic diseases are increasing faster. 11% and 10% of all males’ and females’ CRC cases occur before the age of 50; of all years of potential life lost from CRC, 10% were from the 45-49 age group	The absolute risk of eoCRC is still considerably smaller than the older counterpart; incidence reaches 34 vs 60:100000, respectively
Expected benefits
In the absence of data from randomized controlled studies, three computational models predicted a benefit from lowering the age of screening	Computational models have several limits. They assume an unrealistic 100% adherence rate; they failed to consider CRC as a multifactorial disease where other risk factors influence one’s risk (i.e., sex, diabetes, diet, lifestyle and others)
Sustainability
Earlier screening is economically feasible in the United States, and it might be similarly feasible in most European countries; some European countries have also reported a shortage of gastroenterologists	Earlier screening will create care costs that may not balance the reduced incidence and mortality; implementing earlier screening might produce resource diversion. Enhancing compliance rates to colorectal screening is an equally important task that might be overlooked if excessive emphasis is placed on earlier screening
Society guidelines
The ACS recommends screening from 45 years of age. ACG and ASGE support screening from 45 years of age for African Americans, whose incidence of eoCRC is superimposable on Caucasians	USPSTF, USMSTF and ECCSGWG support screening from 50 years of age

eoCRC: Early-onset colorectal cancer; CRC: Colorectal cancer; ACS:American Cancer Society; ACG: American College of Gastroenterology; ASGE: American Society of Gastrointestinal Endoscopy; USPSTF: United States Preventive Service Task Force; USMSTF: United States Multi-Society Task Force on colorectal cancer; ECCSGWG: European Colorectal Cancer Screening Guidelines Working Group.