Background: In a previous study, we found that Gadobenate dimeglumine (Gd-BOPTA) resulted in a significantly greater Gd uptake by brain tumor tissue than Gadopentate dimeglumine (Gd-DTPA). Therefore, we investigated whether Gd-BOPTA is an efficient agent for neutron capture therapy (NCT).
Materials and methods: Four groups of Fisher344 rats (control, neutron (n), n+ Gd-DTPA, n+ Gd-BOPTA) were subcutaneously injected 9L gliosarcoma cells in both hind legs. Gd-BOPTA and Gd-DTPA (0.05 mmol/g tumor weight) were injected directly into the tumor. At the peak of Gd uptake, thermal neutron irradiation was applied.
Results: Two Gd+ groups showed pronounced tumor growth delay as compared with the control and neutron groups (p = 0.0053, 0.0064, respectively). Furthermore, the BOPTA group showed significantly prolonged delay of tumor growth as compared to the DTPA group (p = 0.033).
Conclusion: This is the first report of Gd-NCT to demonstrate that Gd-BOPTA serve as an effective compound for NCT. Better cytocidal effects of Gd-BOPTA warrant further investigation of subcellular Gd distribution.