TC-99(M)-LABELED CHIMERIC HUMAN MOUSE ANTIGRANULOCYTE ANTIBODY BONE-MARROW SCINTIGRAPHY - A PRELIMINARY CLINICAL-STUDY/

Bone marrow scintigraphy using Tc-99(m)-labelled chimeric anti-granulo cyte antibody (anti-NCA-95) was performed in 17 patients with haematol ogical disorders and skeletal metastases. Chimeric anti-NCA-95 antibod y (chNCA95 Ab, 0.2 mg) labelled with 444 MBq Tc-99(m) was administered to obtain bone marrow images 4 h post-injection. One week later, an I n-111-chloride bone marrow scan was performed on nine patients with ha ematological disorders. Lumbar bone marrow-to-background (L/B) and ili um-to-background (I/B) uptake ratios were calculated for each scan. In six patients with suspected skeletal metastases, Tc-99(m)-HMDP bone s cans were performed. No patient had any adverse reaction or any immune reaction over 20 weeks. In the patients with haematological disorders , the L/B and I/B ratios of the Tc-99(m)-chNCA95 Ab scan were 3.41 +/- 0.90 and 1.23 +/- 0.31, whereas those of the In-111-chloride scan wer e 1.58 +/- 0.32 and 1.00 +/- 0.32, respectively. In assessing findings of irregular central bone marrow uptake and peripheral expansion of t he bone marrow, the Tc-99(m)-chNCA95 Ab scan was much better than the In-111-chloride scan. In the six patients with suspected skeletal bone metastases, three true-positive and two true-negative results were ob served. This preliminary study has revealed that Tc-99(m)-chNCA95 Ab s canning is safe and useful in the diagnosis of haematological disorder s and skeletal metastases. ((C) 1998 Lippincott-Raven Publishers).