TORONTO — Ontario will lower the recommended starting age for colorectal cancer screening to 45 from 50 beginning July 1, according to new guidelines published by Cancer Care Ontario.An Ontario Health document outlining the changes says the decision follows a “notable” increase in younger people being diagnosed with colorectal cancer.The province said the change is based on recommendations from an expert panel, evidence showing an increase in early-onset colorectal cancer in Ontario, and modelling suggesting earlier screening can reduce both the incidence of the disease and mortality rates.Ontario’s Ministry of Health said the updated screening program is intended to improve early detection and treatment outcomes. The move follows the province’s decision two years ago to lower the starting age for breast cancer screening to 40 from 50.Prince Edward Island became the first province to lower its colorectal cancer screening age to 45 earlier this year.Organizations including Colorectal Cancer Canada and Canadian Cancer Society have called on provinces and territories across Canada to adopt similar measures. The groups cite research indicating people under 50 are now between two and 2.5 times more likely to be diagnosed with colorectal cancer than previous generations.Countries including the United States and Australia have also lowered their recommended screening age to 45.Routine colorectal cancer screening in Ontario uses a fecal immunochemical test, known as a FIT test, which allows patients to collect a stool sample at home and submit it to a laboratory for analysis. Individuals with normal results are advised to repeat the screening every two years..Patients whose FIT test detects blood in the stool are referred for a colonoscopy to determine whether cancer is present.The province said invitations for screening will be distributed in phases, but physicians will be able to order FIT tests for patients aged 45 to 49 beginning July 1.Ontario is also lowering the recommended age for colonoscopy screening for individuals with an immediate relative who was diagnosed with colorectal cancer before age 60.Under the updated guidelines, those individuals will begin screening at age 40, or 10 years earlier than the age at which their youngest relative was diagnosed, whichever comes first. Colonoscopy screenings for that group will occur every five years.Individuals with one immediate relative diagnosed at age 60 or older will now be screened using FIT tests every two years beginning at age 45 instead of receiving a colonoscopy.The province said evidence suggests individuals in that category face a similar level of risk as the general population. Officials also said the change is expected to reduce wait times for colonoscopies among patients with abnormal screening results.Ontario Health said health-care providers should expect a “modest increase” in abnormal test results as more people become eligible for screening.The guidance also noted the province anticipates increased demand for colorectal cancer surgeries and pathology services in the short term, though volumes are expected to stabilize as more pre-cancerous growths are detected and removed earlier.