Disease progression during immunotherapy in colorectal cancer does not always indicate treatment failure. A case argues that carcinoembryonic antigen (CEA) may serve as an early marker to distinguish between pseudoprogression and real progression. Presentation of results from reintroduction of chemotherapy after progression on immunotherapy that suggest increased efficiency.
Keywords: carcinoembryonic antigen; colorectal cancer; immunotherapy; pseudoprogression; reintroducing chemotherapy.