Bone marrow is the primary site for many hematologic disorders. To date, however, no suitable bone marrow imaging method has been found. The present study investigates the usefulness of bone marrow immunoscintigraphy using 99mTc-labeled antigranulocyte antibody (anti-NCA-95) in 31 patients with hematologic disorders.
Methods: One milligram of antibody labeled with 259-370 MBq 99mTc was injected intravenously, and bone marrow images were taken 4 hr later. We also calculated the uptake ratios of lumbar bone marrow-to-background (L/B) and ilium-to-background (I/B).
Results: Of 15 patients with aplastic anemia, 7 showed diffusely decreased antibody uptake (L/B = 2.3 +/- 0.8, I/B = 3.0 +/- 0.8) compared to control patients (n = 21, L/B = 8.2 +/- 2.5, I/B = 10.3 +/- 3.1) Six patients had both decreased and increased uptake areas and two had normal to slightly increased uptake. Of those patients receiving various types of therapy for aplastic anemia, all but one showed increased or irregular uptake. The degree of antibody uptake in the bone marrow correlated with peripheral blood analyses (hemoglobin, white blood cells, platelets). Of six patients with myelodysplastic syndrome, four had irregular uptake and two diffusely decreased uptake. Four patients with myelogenous leukemia showed normal uptake, whereas two with lymphocytic leukemia had decreased uptake. Patients with iron deficiency anemia, pure red cell aplasia or thalassemia minor exhibited normal uptake with bone marrow expansion.
Conclusion: Immunoscintigraphy with antigranulocyte antibody is a useful method for evaluating the bone marrow status of patients with various hematologic disorders.