[Predicting of the period of recurrent for a post-operative glioblastoma after radiochemotherapy using 201TlCl SPECT].

After radiochemotherapy for a post-operative glioblastoma multiforme (GB), the majority of patients return at a later date with a recurrent. To assess whether 201TlCl uptake can be used as a prognostic indicator in patients with GB, we measured the ratio of 201TlCl uptake in tumor to 201TlCl uptake in normal brain (TL index) in 10 patients at the end of radiochemotherapy and followed all the patients until they returned with a recurrent. The TL indices at the end of radiochemotherapy indicated 1.36 to 6.82 (mean +/- SD; 3.59 +/- 1.84), and the terms of tumor recurrent were 3-12 months (5.55 +/- 3.10 month). There was a significant negative correlation between the TL indices and the terms of tumor recurrent (y = -1.28x + 10.14, r = 0.760, p < 0.01). Especially, three cases indicated less than 2.0 did not returned with a recurrent in 8 months and 7 cases more than 2.0 returned with a recurrent in 5 months. This study resulted that 201TlCl SPECT was clinically useful to predict the period of recurrent for GB.