Cancer of the breast and beta 2 microglobulin

In carcinoma of the breast the disease stage at diagnosis determines therapy and is closely related to prognosis. To date no single biochemical marker of disseminated breast cancer has been described although beta 2 microglobulin values in the serum have been suggested as a discriminant between localized and systemic disease. Using a new method of beta 2 microglobulin estimation, we carried out a prospective study of levels in 53 patients with breast cancer who were studied repetitively over a 2 yr period. No relationship could be determined between beta 2 microglobulin values and the stage of the disease. Moreover beta 2 microglobulin levels, even when elevated, did not predict early metastasis. Repeated beta 2 microglobulin estimations during treatment of metastatic disease had limited usefulness in that patients with responsive disease usually showed a fall in beta 2 microglobulin, whereas there was generally no change in non-responsive patients. These changes were, however, often within the normal range and seemed to offer a marginal improvement in assessment.