Rapid Genomic Profiling of Colon Cancers Improves Therapy Selection

Colorectal cancer is a malignant tumor arising from the inner wall of the large intestine (colon) or rectum. Colorectal cancer is the third leading cause of cancer in both men and women in the USA. Most colorectal cancers develop from polyps. Removal of colon polyps can aid in the prevention of colorectal cancer.

Treatment of colorectal cancer depends on the location, size, and extent of cancer spread, as well as the health of the patient. Management of colorectal cancer warrants mutational analysis of KRAS/NRAS when considering anti–epidermal growth factor receptor therapy and BRAF testing for prognostic stratification.

Scientists at the Geisel School of Medicine (Lebanon, NH, USA) and their colleagues enrolled 874 colorectal cancer cases from 20 laboratories between November 2017 and December 2018. The teams compared a new cartridge-based laboratory testing device called the Idylla automated system (Biocartis US, Inc, Jersey City, NJ, USA) using the KRAS and NRAS-BRAF cartridges to current standard-of-care testing methods.

The multicenter teams reported that the average turnaround time for test results could be cut by more than 65% from 15 days to five days, with some results available in a single day. The significant decrease in wait time means patients can begin appropriate treatments for colorectal cancer much sooner. The simplicity and ease of use of the new technology compared with other molecular techniques also makes it suitable for integration into clinical laboratories of any size, including those that may not have much molecular expertise.

In collecting the data, the study also addressed the use of minimal tissue from the patient sample. Gregory J. Tsongalis, PhD, a Professor of Pathology and Laboratory Medicine and senior author of the study, said, “One of the study sites included several 1-mm tissue biopsy samples, showing that even smaller tissue-based specimens can be successfully analyzed by Idylla. Our results are in line with findings of other studies showing successful analyses using very small tissue amounts, including those deemed too small for standard molecular testing methods.”

The authors concluded that the described cartridge-based system offers rapid and reliable testing of clinically actionable mutation in colorectal cancer specimens directly from formalin-fixed, paraffin-embedded tissue sections. Its simplicity and ease of use compared with other molecular techniques make it suitable for routine clinical laboratory testing. The study was published on June 11, 2020 in the American Journal of Clinical Pathology.