Concomitant accelerated hyper-fractionated radiotherapy and temozolmide in the treatment of high grade astrocytoma

الملخص EN

Purpose : to evaluate the safety and efficacy of accelerated hyper-fractionated radiotherapy combined with tem-ozolomide in patients with high grade astrocytoma.

Methods and materials : Twenty-four patients with newly diagnosed and histologically proven high grade as-trocytoma were enrolled into this study.

Treatment protocol included radiotherapy delivered in fractions of 150 cGy 3 times daily with at least 4-hour intervals between fractions to a total dose 4050 cGy.

The target volume was the tumor plus the edema with a 2-cm margin.

A boost of 1800 cGy was given to the tumor plus a 2-cm margin to a total dose of 5850 cGy delivered in 39 sessions over 2.5 weeks.

Temozolomide dose was (150 mg / m2 / dayx7d / wk) given 2 hours prior to radiotherapy, from the beginning till the end of the course.

Results : of the 24 patients included 5 (21 %) developed G2 and G3 neutropenia, and 4 patients (17 %) developed G2 and G3 thrombocytopenia.

Non-hematologic toxic-ities were : G2 and G3 vomiting in 8 (33 %) patients, G2 and G3 fatigue in 13 (54 %) patients, G2 skin rash in 4 (17 %), and G2 acute radiation reaction in 2 (8 %) patients.

The twelve months and 18 months survival rates were 67 % and 51.5 % respectively.

Patients aged < 45 years and those who underwent debulking surgery had better survival rates (69 % and 70 %) in comparison to those aged ≥ 45 years and those who underwent biopsy only (27 % and 36 %).

Conclusion : temozolomide in a daily dose of 150 mg/ m2 concomitant with thrice daily fractions of 150 cGy for a total dose of 5840 cGy is a safe and tolerable regimen in terms of acute toxicities, however long term follow-up is required for proper assessment of late toxicities.

The results achieved are promising and need to be confirmed in a randomized trial comparing accelerated hyper-fractionated radiotherapy with and without temozolomide.