Does signet ring cell adenocarcinoma (colon) produce a CEA?
Answer At least not always. Sorry, these tumours are RARE, so experience is very limited. There are reports with CEA elevation in blood, but also reports with no such elevation. There are also some definition problems with regards to what you mean by “signet cell carcinoma”. Some such cells can often also be seen in “ordinary” adenocarcinomas and there is a middle group called mucinous carcinomas. Histochemically however CEA has been demonstrated WITHIN the cells of signet cell carcinomas. All this complicates an evaluation!
