[Difference in 201TlCl accumulation mechanism in brain tumors: a comparison of their Na(+)-K+ ATPase activities].

ABSTRACT

The accumulation levels of 201TlCl and Na(+)-K+ ATPase activity in tumor tissue were compared among glioblastoma, benign glioma and meningioma to study the difference in the mechanism of 201TlCl accumulation. The subjects were 19 cases comprised of 6 glioblastoma, 2 oligodendroglioma, 1 fibrillary astrocytoma, 1 pilocytic astrocytoma and 9 meningioma. Preoperative 201TlCl SPECT was performed in all the cases, and Thallium Index (TL index) was calculated by a ratio of 201TlCl in the tumor area and the contralateral area. In addition, cell membrane was extracted from the tumor tissue collected intraoperatively to determine Na(+)-K+ ATPase activity. No statistically significant difference in TL index was noted between the glioblastoma group (6.97 +/- 2.67) and the meningioma group (5.87 +/- 1.99). This fact showed that there was no difference in the accumulation level of 201TlCl between the two groups. On the other hand, the glioblastoma group indicated a higher value of Na(+)-K+ ATPase activity (49.13 +/- 43.76 mumole/hour/mg protein) than the meningioma group (7.73 +/- 13.84 mumole/hour/mg protein) (p < 0.05, t test). These results suggested the involvement of Na(+)-K+ ATPase activity in 201TlCl accumulation in glioblastoma and the influences of other accumulation mechanism than Na(+)-K+ ATPase activity such as the volume of intratumoral vascular bed in meningioma.