Taha Qazi, MD: Best Screening for Colorectal Cancer

The conversation of colorectal cancer screening methodology has been resonant in gastroenterology for years now, as patient and clinician preference for colonoscopy versus noninvasive screening tools has become closer to a debated subject than previously known.

In the middle of this topic is the pursuit of refinement for the noninvasive screening tools that would possibly rival colonoscopy, the tried and true method for gastroenterologists still.

In the third issue of Qazi Corner—a collaborative quarterly newsletter on gastroenterology research, news, and trends between HCPLive and editor-in-chief Taha Qazi, MD—included a systematic review and meta-analysis of fecal immunochemical test (FIT) versus FIT-DNA for the rate of detection of sessile serrated polyps (SSPs) in individuals undergoing average colorectal cancer risk screenings.

Authored by Rajat Garg, MD, the analysis found FIT-DNA outperformed FIT tests in detecting both SSP and advanced serrated poylps in screened individuals—though long-term benefit of either tool on the incidence and mortality of colorectal cancer is still of question.

In the second segment of an interview with HCPLive, Qazi, a gastroenterologist with the Cleveland Clinic, discussed the value of interpreting SSP detection rates in screening.

“The best way to describe sessile serrated polyps is that they tend to in many ways be very similar to adenomas, meaning they can develop into cancer and they are premalignant lesions,” Qazi said. “We do know that FIT and FIT-DNA testing are pretty efficacious in evaluating for adenomatous lesions; is that efficacy still true in the context of sessile serrated polyps is what our colleagues were looking at.”

On the subject of emerging noninvasive screening tools for colorectal cancer relative to colonoscopy, Qazi expressed hope that better options and refined testing will become apparent in the coming years. The current issue, he noted, is the average sensitivity score of such tools is in the 70 – 80% range.

“Although they are helpful in managing or evaluating as a blood or stool test, there is still always this concern that we’re missing lesions in these situations,” Qazi said. “As a preventable illness, I think colon cancer represents an area where we can eliminate the polyp-to-cancer ratio.”

Qazi predicts the future entails a methodology where noninvasive screening or surveillance precedes colonoscopy, which is then used more ideally in the presence or high risk of polyps. Until then, the latter remains the chief option.

“(Colonoscopy) has the ability to not only diagnose, but also provide therapeusis with polypectomy, which continues to be an issue we haven’t been able to address with our prior studies,” Qazi said.

Read Garg’s review and analysis of FIT versus FIT-DNA from Qazi Corner Issue 3 here.