Serum sialic acid--an important cancer marker.

Total serum sialic acid (TSA), Lipid associated sialic acid (LASA), Total protein (TP) and TSA/TP factor (as cancer markers) have been estimated in 78 patients of cancer stomach, breast, colorectal region and gall bladder, before and after treatment and of varying degrees of metastasis and compared to 30 healthy controls. A significant rise in TSA and TSA/TP factor and a decrease in serum total protein levels was found in all cases of cancer. This increase was directly proportional to the degree of metastasis i.e. tumour burden. Serum TP levels were found decreased in all patients. Rise in LASA levels was not significant. Raised TSA/TP levels became lower to certain extent after effective therapy. Hence it can be inferred that although TSA and TSA/TP are not specific they are however, sensitive markers regarding detection of malignancy and useful in monitoring cancer progression and/or recurrent while evaluating the efficacy of various cancer therapies.