Thallium-201 in brain tumors: relationship between tumor cell activity in astrocytic tumor and proliferating cell nuclear antigen.

Abstract

This study was performed to assess the relationship between 201Tl chloride uptake and brain tumor proliferation using monoclonal antibody Ki-67 and proliferating cell nuclear antigen (PCNA). Thirty-four patients with brain tumors were studied. Serial SPECT images were recorded 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 monoclonal antibody staining. Thallium-201-chloride indices of the astrocytoma were 1.73 +/- 0.17 and 1.48 +/- 0.07 on early and delayed images, respectively. On the other hand, 201TI indices for anaplastic 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 between the 201TI (delay) and Ki-67 indices for astrocytic tumor. There were no significant differences between Ki-67/PCNA indices and washout rates. There was a positive correlation between PCNA but not the Ki-67 labeling index and the 201Tl index. With the use of a noninvasive technique, 201TI index supports the PCNA index.