抄録
Vincristine and vinblastine possess antimitotic activities with arrest of cycling cells in metaphase. These drugs were utilized to analyze the growth characteristics of 12 human gliomas (6 glioblastomas, 4 anaplastic astrocytomas, 2 well differentiated gliomas). The patients received 3H-thymidine and mitostatic agents (either 0.1 mg/kg of Velban or 3 mg/m2 of Oncovin) prior to tumor biopsy. To allow for more convenient comparison of the mitotic index (MI) and the labeling index (LI) in the prognosis of patients, a normalized value (MI/t) was computed by dividing the MI by the lapsed time between drug administration and biopsy. Most malignant gliomas had a MI/t value of 4-5×10-3, a LI of 5-15%, and a potential doubling time of 8.7±3.3 days. In contrast, well differentiated gliomas had a MI/t value of <0.6×10-3 and a LI of 1.9% or less. Patients whose tumors had a MI/t value of > 2×10-3 and/or a LI of > 5% died within 6 months after biopsy. Postmortem examination of specimens from 4 glioblastomas revealed very few, inconsistent mitoses (MI ?? <0.5×10-3). Thus, MI/t values obtained with the use of mitostatic agents should have prognostic significances similar to the LI. Although many uncertainties still exist, the use of mitostatic agents in the study of human brain tumor growth kinetics offers some advantages such as: mitostatic agents are not radioactive; single doses of these drugs are virtually harmless; the method is simple to apply; and, the results can be obtained very quickly.
