Changes in serum acute phase proteins in breast cancer patients receiving methotrexate infusion therapy.

The serum concentrations of six glycoproteins (alpha 1-acid glycoprotein, AGP; haptoglobin, Hp; alpha 1-antitrypsin, AT; ceruloplasmin, Cp; prealbumin, PALB; and alpha 2-macroglobulin, MACRO) have been estimated serially in nine advanced breast cancer patients who received a total of 24 intravenous infusions of methotrexate (MTX). The serum glycoprotein levels taken before the first drug exposure did not relate with the prognosis of these patients. In eight patients, constantly high or rising levels of AGP, Hp and AT during consecutive infusions of the drug were associated with continued metastatic disease. A transient tumour regression occurred in one patient which correlated with falling serum levels of these proteins into the normal range. The serum levels of Cp, PALB and MACRO did not correlate with the clinical status of these patients during treatment. Possible factors which may influence the serum levels of these glycoproteins in cancer patients during therapy are discussed.