How is CRC staged?
At the time of surgery, the tumor and accompanying lymph nodes are removed and sent to the pathology laboratory. Lymph node testing currently involves microscopic examination in which one or more thin slices of each lymph node are examined. This represents less than 1% of the available tissue, leaving 99% unexamined. Further, microscopic testing can detect only one cancer cell in 200 normal cells. One particular area in question with the staging of colorectal patients is whether stage I and II patients should get additional treatment after surgery. While initial testing of the lymph nodes has not detected cancer cell clusters, studies have shown that up to 30% of these patients experience a recurrence of their cancer, presumably due to cancer metastases missed during the testing. Fortunately, breakthroughs in genetic testing are opening options that test the lymph nodes with much greater sensitivity. The Previstage™ GCC Colorectal Cancer Staging Test examines 50% or more of each lymph
