Determination of cancer antigen ca 15-3, in breast carcinoma

ABSTRACT

In breast carcinoma, carbohydrate antigen 15-3 [CA 15-3], a mucin component, is the most important and commonly used tumor marker. It is a transmembrane glycoprotein containing a large extracellular domain of 69 amino acids. Several studies suggested that its evaluation could provide valuable clinical information. Assessment of CA 15-3 can also be useful during treatment of Breast cancer as well as to detect recurrence following primary treatment. CA 15-3 is a breast-cancer-associated antigen defined by reactivity with two monoclonal antibodies, DF3 [raised against a membrane-enriched fraction of human breast cancer] and 115D8 [raised against antigens of human milk fat globule membrane]. The main clinical application of CA 15-3 suggested being in monitoring the response to the treatment and gives reliable information on the recurrence of the disease. The aim of present study is to assess CA 15-3 in patients with breast carcinoma and its usefulness in monitoring and therapy. Serum samples of female patients [n = 56] suspected of or diagnosed with breast carcinoma were analyzed for CA 15-3. Significantly elevated levels were noted in most of the patients and correlated with their malignant tumor status and clinical conditions. It is concluded that CA 15-3 is currently the most widely used circulating cancer marker for breast carcinom·a. CA 15-3 can provide useful information regarding successfulness when comparing pre-operative and post-operative values. In our study, breast carcin9ma patients showed decrease in CA 15-3 levels post-operatively [although most of them still above normal reference range], depicting successfully of treatment and intervention, in addition to suggesting that CA 15-3 concentrations can also provide prognostic information. Furthermore, serial concentrations analyses have the potential both to detect recurrences pre-clinically and to monitor the treatment of metastases breast carcinoma