When, if ever, would you initiate chemotherapy for recurrent colorectal cancer based on a positive ctDNA assay alone, such as Signatera, in the absence of tumor on imaging or physical exam?
Answer from: Medical Oncologist at Academic Institution
No. There are many ongoing trials to look at this question and stay tuned for a soon in press JCO review that will reference many of the studies but currently, no data to treat based on a positive test. I will be more mindful of surveillance i.e., a 3-month scan, for example.
Answer from: Medical Oncologist at Community Practice
I also agree that I would not initiate therapy. The use of ctDNA for surveillance has posed a problem for me as to what I would do with the information and whether I am causing trauma to the patient without improvement in survival, just lead time. However, the possible use of PET to find disease and...
Answer from: Medical Oncologist at Community Practice
Agree with Dr. @Aparna R. Parikh. Couple of additional thoughts:
In addition to the surveillance with cross sectional imaging, switching out the modality can often identify what a CT scan missed (PET/CT, MRI [liver or pelvis], or a diagnostic lap - in the appropriate clinical context). Often have...