Why does NCCN still not recommend using circulating tumor DNA to guide adjuvant chemotherapy in stage II colon cancer when colon cancer experts are currently embracing the practice?  

While I cannot speak to that panel itself, I can support the very rigorous process that all NCCN guidelines undergo, and I surmise that the reason why ctDNA is not yet recommended is because there is no consensus that: It is better than CEA and good quality cross-sectional imaging (see, for example...

The NCCN guidelines state that ctDNA is a prognostic marker, but there is currently insufficient evidence to recommend routine use of ctDNA assays outside of a clinical trial for adjuvant therapy decision-making in stage II colon cancer. ctDNA is a robust prognostic marker for recurrence risk; patie...

At diagnosis, the landmark sensitivity from GALAXY-Japan for a high-quality tissue-informed test of 1 postoperative test is about 50% which improves to 70% on surveillance. The false negative rate, therefore, is 50% initially at the adjuvant therapy decision time point (takes 6 weeks to generate a t...

I’m not sure I agree with the premise that colon cancer experts are broadly “embracing” the use of ctDNA to guide adjuvant therapy. At least in my experience, its use is far from universal, and there are important caveats that need to be discussed with patients before ordering it. ...