Virtual colonoscopy identifies asymptomatic cancers outside the colon

Unsuspected extracolonic cancers can be detected with virtual colonoscopy screenings, according to a study published in the journal Radiology (2010;255(1):83-8).

The study, led by Perry Pickhardt, MD, professor of radiology and chief of GI Imaging, at the University of Wisconsin School of Medicine & Public Health, reviewed the medical records of 10,286 adults who had undergone colorectal cancer screening with virtual colonoscopy.

The results revealed that the overall detection rate of unsuspected cancer is approximately 1 per 200 asymptomatic adults undergoing routine screening CT colonography. Researchers identified unsuspected cancer in 58 patients, which included invasive colorectal cancer in 22 patients and extracolonic cancer in 36 patients. Extracolonic malignancies included renal cell carcinoma, lung cancer, non-Hodgkin lymphoma, and a variety of other tumors. The authors explained that detection and treatment at an early presymptomatic stage may have contributed to the favorable outcome.

“Although extracolonic evaluation at screening CT colonography does carry some disadvantages, such as patient anxiety, inconvenience, or the potential for benign biopsy, our results suggest that early detection of asymptomatic extracolonic cancer represents an additional benefit of screening CT colonography that is not available with optical colonoscopy,” Dr. Pickhardt concluded. “Virtual colonoscopy is an accurate, safe and convenient screening test that could potentially be a life-saving examination.”