TY - JOUR T1 - The Diagnostic Value of <sup>123</sup>I-IMP SPECT in Non-Hodgkin's Lymphoma of the Central Nervous System JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1777 LP - 1783 VL - 41 IS - 11 AU - Yasuhiko Akiyama AU - Kouzo Moritake AU - Toshiki Yamasaki AU - Yoriyoshi Kimura AU - Akira Kaneko AU - Yoshiaki Yamamoto AU - Takeshi Miyazaki AU - Mitsuhiro Daisu Y1 - 2000/11/01 UR - http://jnm.snmjournals.org/content/41/11/1777.abstract N2 - N-isopropyl-p-[123I]iodoamphetamine (IMP) SPECT is of low diagnostic value in patients with brain tumors, because brain tumors are visualized as uptake defects. Some reports have described non-Hodgkin's lymphoma of the central nervous system (CNS) as showing high uptake on delayed 123I-IMP SPECT images, suggesting its usefulness in diagnosing CNS lymphoma. In this study, we investigated the clinical value of 123I-IMP SPECT as a diagnostic tool for CNS lymphoma. Methods: Ninety-six patients with brain tumors, including 12 patients with CNS lymphoma, underwent 123I-IMP SPECT. Eleven patients had primary CNS lymphoma, and 1 had a parenchymal brain metastasis from a breast lymphoma. The total number of lesions was 18, 14 of which were in the cerebral parenchyma, 3 in the brain stem, and 1 in the ventricle. Early SPECT images were initiated 15–30 min after intravenous injection of 111 MBq 123I-IMP, and delayed images were collected 4 h later. SPECT images were visually analyzed with a color-grading scale. Tumor-to-normal activity ratio (T/N) and tumor-to-cerebellum activity ratio (T/C) were calculated for both early and delayed images for semiquantitative analysis. Results: By visual estimation, more than a 3- cm3 volume of CNS lymphoma was detected as an obvious focus of increased accumulation on delayed images. All other brain tumors tested appeared as decreased accumulation on delayed images. T/Ns and T/Cs on delayed images of CNS lymphomas, including tumors less than 3 cm3 in volume, were 1.48 ± 0.42 and 1.08 ± 0.16, respectively. These ratios in patients with glioma (0.30 ± 0.05 and 0.31 ± 0 07 respectively) or meningioma (0.34 ± 0.10 and 0.41 ± 0.17, respectively) showed a significant difference from those in patients with CNS lymphoma (P &lt; 0.0005). Conclusion: 123I-IMP SPECT is a helpful tool for diagnosing CNS lymphoma. ER -