ALPHA INTERFERON RAISES SERUM BETA-2-MICROGLOBULIN IN PATIENTS WITH MULTIPLE-MYELOMA

Serum beta-2-microglobulin (beta-2m) levels were followed in eight patients with multiple myeloma who were treated with leucocyte alpha interferon (alpha-IFN) 6 x 10(6) IU daily for 1-2 weeks before chemotherapy. Serial measurements of serum beta-2m were carried out regularly during the first week on alpha-IFN. A rise in beta-2m was observed in all patients, with maximum increments ranging from 29% to 185% (mean 109%). The increase in beta-2m was most marked in patients with elevated pretreatment levels of serum beta-2m and creatinine. In six patients the peak value was reached between the third and the fifth day, after which the levels decreased. In two patients serum beta-2m remained elevated for 3 and 4 months, respectively. A marked increase in serum beta-2m can be induced by alpha-IFN in myeloma, which should be taken into consideration when using beta-2m for the assessment of tumour response during alpha-IFN therapy.