COMPARISON OF TC-99M METHOXYISOBUTYLISONITRILE AND GA-67-CITRATE SCANNING IN THE ASSESSMENT OF LYMPHOMAS

The aim of this study was to compare the value of scintigraphy using t echnetium-99m methoxyisobutylisonitrile (MIBI) with that of scintigrap hy using gallium-67 citrate in the assessment of Hodgkin's disease and non-Hodgkin's lymphoma and to relate these results with those of CT s can and MRI. Fifty-eight patients were included either for a follow-up examination or for monitoring of their treatment. Twenty-three residu al masses were studied. A whole-body scan was performed, followed by s ingle-photon emission computed tomography (SPET) 20 min after injectio n of 740 MBq of Tc-99m-MIBI and 72 h after injection of 185 MBq of Ga- 67 citrate. The overall sensitivity of Tc-99m-MIBI and Ga-67 citrate w as 71% and 68%, respectively, and the overall specificity was 76% and 44%, respectively, For residual masses, the sensitivity was 44% with b oth tracers and the specificity was 80% with Tc-99m-MIBI and 53% with Ga-67 citrate. The positive predictive values were 85% and 68% and the negative predictive values were 59% and 44%, respectively, The signal -to-background ratio was 1.5 for Tc-99m-MIBI and 2 for Ga-67 citrate. At present, Tc-99m-MIBI cannot replace Ga-67 citrate in the assessment of lymphomas.