Is serum beta 2 microglobulin a useful marker in patients with breast cancer?

In a study of 19 patients with breast cancer serum beta 2 microglobulin (beta 2 mu) was evaluated as a tumour marker. Serum beta 2 mu did not correlate with tumour stage, survival time, or histological differentiation grade. Nor did a change of serum beta 2 mu reflect a change of tumour mass. Additionally, serum beta 2 mu lacks specificity and sensitivity, as only 21% of our patients had an increased serum beta 2 mu.