Plasma sialyltransferase in patients with breast cancer

Sialyltransferase enzyme levels (Sialtx) CEA, and 10 standard laboratory tests were studied in 50 patients with treated, recurrent, or disseminated breast carcinoma. All groups of patients had elevated mean Sialtx activity (CPM/mg protein) as compared with normal controls. Sialtx levels (expressed as % of normal controls) of patients with disseminated lesions were significantly elevated as compared to patients without evidence of disease or with only soft tissue recurrences, whereas CEA and alkaline phosphatase levels were significantly elevated (peripheral blood lymphocyte count, total protein and albumin levels significantly decreased) in patients with recurrent disease of all sites. Among patients with disseminated breast cancer and normal CEA levels, about 50% had markedly elevated Sialtx activities. From our limited experience, it appears that Sialtx study is of value when CEA failed to indicate the presence of breast malignancy. Further testing including serial studies should be done to better define its clinical usefulness.