Tissue distributions differ accordingto physio/pathological conditions, while there is an overproductionof CA IX and XII isoenzymes in hypoxic tumors, CA VA and XIV are predominantin the liver.5 Increased expression ofCA IX is seen in most solid cancers including colorectal, breast,and pancreatic tumors.6 This overproductionof tumor-specific CA IX and XII isoenzymes has also been shown incell culture studies. Here, CA9 is linked to neoplasm.