Repeated salvage high precision radiotherapy for repeated recurrence of high-grade glioma.

BACKGROUND

Repeated high precision radiotherapy may be an additional salvage treatment for patients with recurrent high-grade glioma, delivering a low minimum radiation dose to brain and a high effective dose to tumor.

MATERIALS: 24 patients with high-grade gliomas (grade 3: 8 patients, grade 4: 16 patients) were treated by surgery, chemotherapy, and tomotherapy (CT-guided intensity-modulated radiotherapy (IMRT)). A total dose of 60 Gy was prescribed to PTVh (planning tumor volume h) and 40 Gy to PTV1 in 15 fractions each. PTVh and PTV1 were defined as the MRI contrast-enhanced area plus a margin and as high intensity area on the double inversion recovery images plus a margin, respectively. The planning for distant recurrence was performed as well as the first tomotherapy, and for invasive recurrence, 40 Gy or lower was prescribed to PTVh.

RESULTS

The tomotherapy was performed for 14 of the 24 patients for the first recurrence, and for 7 of those 14 patients for the second or subsequent. Stepwise multiple regression analysis showed that patients with repeated tomotherapy had long survival time (p < 0.0001). Median survival time from the first tomotherapy (based on Kaplan-Meier estimates) was 18 months in the 14 patients with repeated tomotherapy versus 5.5 months in the 10 patients without repeated tomotherapy (p < 0.0001).

CONCLUSION

Repeated tomotherapy may be one of the additional salvage treatments without symptomatic adverse events for patients with repeated recurrences of glioma. Accurate and precise tomotherapy planning and neurosurgery for eloquent areas are essential for the comprehensive treatment of glioma patients.