Immunotherapy has not been used long enough on CRC to have been on it for the recommended period (24 months) and off it long enough to answer your questions. MY oncologist, who has used the Keytruda since its FDA approval in 2015, said that in other types of cancer after stopping the drug, in some cases the cancer comes back and generally, the recurring cancer does not respond to immunotherapy again. In other instances, where the patient has terminated use of the immunotherapy (often times prior to the 2-year recommended treatment period) the cancer has not returned at all. Obviously, these are antidotal accounts of patient experiences by my oncologist but I don't think we've had a lot of experience with the immunology treatments yet to know how the patients and the cancer will respond over the long term.
Mommy to Jack (8) now (16) and Katie (4) now (12)
(My Most Precious Things)
Dx 8/11 Stage IV CRC (liver mets) CEA 2,600+
9/11 Folfiri 2/12: Failed Liver Resection
5/12 HAI pump/removed primary
4/13 Liver Resection
8/13-12/15 (10) RFAs lungs
5/17: Upper Left Lobe of lung resected.
02/18: 3 new mets lymph nodes lung:
05/18: Keytruda (MSS w/Intermediate TMB): CEA: 66.4, 39.2, 23.8, 13, 3.5 1.8, 1.0, 2.8 3.9, 5.0, 5.6, 1.5, .8, .8, 1.1, 1.1, .7
7/18; 9/18; 11/18; 2/19 Clear CT scans