123I-IMP SPET in the diagnosis of primary central nervous system lymphoma.
We reviewed N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) single-photon emission tomography (SPET) images of brain tumours and assessed the usefulness of 123I-IMP SPET for the diagnosis of primary central nervous system (CNS) lymphoma. We analysed 52 tumours that showed enhancement on magnetic resonance imaging: 11 malignant lymphomas, 3 anaplastic astrocytomas, 17 glioblastomas, 12 meningiomas, 4 metastatic brain tumours and 5 other brain tumours. 123I-IMP uptake in the tumours on early (15-min) and delayed (4-h) scans was visually classified as high, moderate or low as compared with the contralateral brain cortex. Early and delayed 123I-IMP uptake ratios comparing tumours with contralateral brain cortex (T/N ratio) were also calculated. In malignant lymphomas, the visual uptake of 123I-IMP was moderate to high on the delayed scans. The delayed T/N ratios were significantly higher than the early ratios (P<0.05) and all lymphomas, with the exception of one small one, had delayed ratios greater than 0.9. In non-lymphomatous tumours, the visual uptake of 123I-IMP was low on the delayed scans. The delayed T/N ratios were significantly lower than the early ratios (P<0.01) and all non-lymphomatous tumours had delayed ratios of less than 0.8. The T/N ratios of lymphomas were significantly higher than those of non-lymphomatous tumours on both early and delayed scans (P<0.0001). These results suggest that 123I-IMP SPET may be a useful tool in the differential diagnosis of primary CNS lymphoma.
Yoshikai
T
T
Department of Radiology, Saga Medical School, Japan.
Fukahori
T
T
Ishimaru
J
J
Kato
A
A
Uchino
A
A
Tabuchi
K
K
Kudo
S
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D020367:Iofetamine; D008223:Lymphoma / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009423:Nervous System Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals
D019275:Radiopharmaceuticals; D020367:Iofetamine