Hmm.. No.. thats not exactly correct, CEA levels should always be less than 5 µg/l. But levels 5-10 µg/l are in some cases okay (for example smokers can have CEA up til 10 eventho it doesnt mean anything serious), but 11-20 µg/l level gives a suspection of a cancer and over 20 gives a strong cancer suspection.
CEA is usually correlated with the size of the tumor in colorectal cancers. Preoperation levels also correlate the patients postoperative well-being. After a succesful operation the CEA usually goes down to normal level within 6-8weeks. And if the CEA raises again after a surgery it can mean relapsy or metastasis. And it can also raise in other cancers than colorectal, for example pancreatic, breast etc. And if the levels start go up slow it usually means a relapsy but if it goes up fast it usually means that the cancer has spread to other organs.
