[Importance of cerebral tomoscintigraphy using technetium-labeled sestamibi in the differential diagnosis of current tumor vs. radiation necrosis in subtentorial glial tumors in the adult].
CT scan and MR imaging are not always reliable in the differential diagnosis between radionecrosis and recurrence of brain tumor. We describe the results of a prospective study using 99mTc Sestamibi. 22 patients were included. The histology of the tumor was astrocytoma (grade 2-4) oligodendroglioma (grade 2-3) or mixed (grade 2-3). SPECT was performed using a Tomomatic 564, 1 h after the injection i.v. of 370 MBq of 99mTc Sestamibi. Ten slices parallel to the orbitomeatal plane were obtained. Two index were calculated i) CI: ratio of the mean counts in the lesion to the mean counts in the contralateral choroid plexus and ii) MI: ratio of the mean counts in the lesion to the contralateral mirror area. The results were compared to stereotactic biopsies or to clinical course at 6 months. Twelve patients out of 22 showed an increased uptake of the tracer and 11/12 presented with a recurrence. In 10 patients without fixation, 4 were false negative. The sensitivity for the detection of tumor recurrence was 73% and specificity was 85%. The positive predictive value was 91% and the negative predictive value was 60%. The use of a cut-off value superior to 2 for MI and superior to 0.5 for CI appears to be a good criterion for helping the diagnosis of relapse according to the analysis of Receiver Operating Characteristic curves (ROC). A positive SPECT was conclusive for the diagnosis of recurrence but a negative SPECT did not allow to assess the absence of recurrence. Limits of methods have to be stressed and searched for a better understanding of false negatives.
Lamy-Lhullier
C
C
Service Central de Médecine Nucléaire (Unité d'Imagerie Fonctionnelle cérébrale), CHRU, Lille.
Dubois
F
F
Blond
S
S
Lecouffe
P
P
Steinling
M
M
D000368:Aged; D001254:Astrocytoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D001706:Biopsy; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology*; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D016545:Choroid Plexus Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D016371:Cranial Irradiation / Q000009:adverse effects; D003937:Diagnosis, Differential; D005069:Evaluation Studies as Topic; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D005910:Glioma / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D009837:Oligodendroglioma / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D011446:Prospective Studies; D011832:Radiation Injuries / Q000000981:diagnostic imaging* / Q000209:etiology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013238:Stereotaxic Techniques; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
D017256:Technetium Tc 99m Sestamibi
Intérêt de la tomoscintigraphie cérébrale au Sestamibi marqué au technétium dans le diagnostic différentiel récidive tumorale-radionécrose des tumeurs gliales sus-tentorielles de l'adulte.