Differentiation of tumor recurrence from radiation necrosis in high-grade gliomas using 201Tl-SPECT.
MRI is routinely performed to detect recurrence in patients with primary brain tumors, but it may not differentiate recurrent tumor from radiation-induced necrosis reliably. Thallium-201 single-photon emission computed tomography ((201)Tl-SPECT) might be useful in distinguishing between these two clinical entities. In a retrospective study (201)Tl-SPECT studies with corresponding MRI studies in 19 patients with clinical or radiological suspicion of high-grade tumor recurrence were reviewed. The diagnostic accuracies of both modalities were based on the subsequent histology or clinical course where biopsy was not performed. Post-scan histology was available in nine patients (43%) who underwent re-resection. The SPECT result determined management in six patients (29%). Post-SPECT survival was significantly better in patients with negative (201)Tl-SPECT studies compared to patients with positive studies (median survival 15+vs. 6 months) (p=0.04, log-rank test). The sensitivity and specificity of (201)Tl-SPECT in diagnosing tumor recurrence were 83% and 100%, respectively. (201)Tl-SPECT can accurately differentiate tumor recurrence from radiation necrosis in patients with high-grade gliomas and abnormal MRI findings post irradiation. This is reflected in a significantly longer post-scan survival time in patients with a negative (201)Tl-SPECT result.
Department of Medical Oncology, Royal Melbourne Hospital, Parkville, Victoria, Australia. Jeannetie@gmail.com
Jeanne
J
Tie
Dishan H
DH
Gunawardana
Mark A
MA
Rosenthal
D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D005910:Glioma / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000401:mortality; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging; D011832:Radiation Injuries / Q000000981:diagnostic imaging* / Q000473:pathology; D012008:Recurrence; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016019:Survival Analysis; D013793:Thallium; D015899:Tomography, Emission-Computed, Single-Photon
C027549:thallium chloride; D013793:Thallium