Flexible sigmoidoscopy screening recommended in young given left-sided CRC predominance
New research warrants flexible sigmoidoscopy screening starting at age 40 in average risk individuals given the rising incidence of early-onset colorectal cancer and the left-sided predominance of CRC in these patients, according to a presentation at the American Society of Colon and Rectal Surgeons Annual Scientific Meeting.
“This is potentially practice changing,” James M. Church, MD, of the department of colorectal surgery at the Cleveland Clinic, told Healio Gastroenterology. “The biology of colorectal cancer in the young is different to that in the middle aged and the elderly. ... There are significantly more left sided cancers, and in particular rectal cancers. This means that flexible sigmoidoscopy should discover 65% to 83% of cancers or their premalignant polyp stage. The exam could also be combined with occult blood testing to rule out more proximal cancers.”
Church and colleagues retrospectively reviewed all 842 patients aged younger than 50 years diagnosed with CRC at the Cleveland Clinic between 2000 and 2016. After excluding those with a hereditary cancer syndrome or inflammatory bowel disease, researchers analyzed 739 patients (45% women) for the anatomic distribution of their cancers.
These patients received their diagnosis between ages 18 to 49 (median age, 44 years), with 530 diagnosed in their forties, 167 in their thirties, 40 in their twenties and two in their late teens. Moreover, 32% had a family history of CRC.
Regarding the outcome of interest, 65% of cancers were located in the rectum, 15% in the sigmoid colon, 3% in the descending colon and 17% from the splenic flexure to the cecum. Theoretically, 83% of these tumors would therefore be detectable by flexible sigmoidoscopy, Church and colleagues wrote. They observed the same distributions in each age group and in patients with a family history of CRC.
They also acknowledged the data could be “distorted by referral patterns,” but noted that population studies have reported comparable results.
“The practicalities of doing so many flexible sigmoidoscopies need to be discussed but one possibility is the use of nurse endoscopists,” Church said. “We will cover suggestions in the manuscript that we are writing. Something has to be done for these young people who miss out on regular screening but are getting more and more cancers in their colon and rectum.” – by Adam Leitenberger
Church J. Abstract P538. Presented at: American Society of Colon and Rectal Surgeons Annual Scientific Meeting; June 10-14, 2017; Seattle.
Disclosures: The researchers report no relevant financial disclosures.