CLEARANCE OF XE-133 FROM BONE-MARROW IN PATIENTS WITH SMALL-CELL LUNG-CANCER

The aim of this study was to estimate bone-marrow blood flow (BMBF) in man and to correlate this with myelosuppression induced by cytostatic treatment dosed as a function of surface area. Twenty-four patients suffering from small-cell lung cancer participated in the study. Blood flow was measured with the xenon-133 washout technique. The Xe-133 clearance measurement took place in conjunction with the pre-treatment bone-marrow staging procedure (ad modern Radner). Tissue samples were taken for microscopy and for the determination of the blood-to-tissue partition coefficient-lambda. After the bone-marrow aspiration, 0.1-0.2 ml of Xe-133 in saline was injected into the bone marrow and the cannula was removed. Following a hyperaemic phase of 12 min (7-16 min), monoexponential washouts were demonstrated. The median washout rate constant was 0.0063 min-1 (0.0038-0.0098 min-1). Lambda values of 0.3-3.5 ml g were found, but microscopy of the bone marrow showed a fairly large admixture of peripheral blood. Therefore, the lambda-values should be taken with caution and absolute blood-flow values were not calculated. The results demonstrated no correlation between Xe-133 clearance from crista iliaca and leucocyte or platelet suppression.