TL-201 IN BRAIN-TUMORS - RELATIONSHIP BETWEEN TUMOR-CELL ACTIVITY IN ASTROCYTIC TUMOR AND PROLIFERATING CELL NUCLEAR ANTIGEN

This study was performed to assess the relationship between Tl-201 chl oride uptake and brain tumor proliferation using monoclonal antibody K i-67 and proliferating cell nuclear antigen (PCNA). Methods: Thirty-fo ur patients with brain tumors were studied. Serial SPECT images were r ecorded and thallium uptake (Tl index) and washout rates in the tumors were calculated. Imaging results were compared with those from biopsy and histology. Cell proliferation was determined by PCNA or Ki-67 mon oclonal antibody staining. Results: Thallium-201-chloride indices of t he astrocytoma were 1.73 +/- 0.17 and 1.48 +/- 0.07 on early and delay ed images, respectively. On the other hand, Tl-201 indices for anaplas tic astrocytoma were 2.60 +/- 1.05 and 1.76 +/- 0.93 and 3.26 +/- 1.63 and 2.23 +/- 0.56 for glioblastoma. The correlation coefficient betwe en Tl-201 and PCNA indices was 0.68 for astrocytic tumors. There was n o statistically significant correlation between the Tl-201 (delay) and Ki-67 indices for astrocytic tumor. There were no significant differe nces between Ki-67/PCNA indices and washout rates. Conclusion: There w as a positive correlation between PCNA but not the Ki-67 labeling inde x and the Tl-201 index. With the use of a noninvasive technique, Tl-20 1 index supports the PCNA index.