- Surgery followed by radiotherapy combined with chemotherapy is the standard treatment approach for aggressive glioblastomas.
- A recovery period of 4-5 weeks post-surgery is needed before starting radiotherapy, during which the cancer cells continue to grow or become more resistant to radiotherapy and chemotherapy.
- Neo-adjuvant chemotherapy that adds chemotherapy prior to radiotherapy, prevented the tumor from progressing during recovery and increased the patients survival.
A new clinical approach to increase the efficiency of treatment in glioblastomas has been developed. It helped to increase the median survival from 16 months to 22 months, bringing much needed hope to those affected by this aggressive disease.
This promising phase II clinical trial was conducted by a team of researchers of the McGill University Health Centre (MUHC).
"Glioblastomas are very difficult to treat," explains Dr. George Shenouda, radio-oncologist at the MUHC and lead author of the study. "These tumors grow and spread quickly throughout the brain, making it very difficult to completely remove with surgery."
The standard treatment for glioblastomas consists of removing as much of the tumor as possible with surgery and then eliminating what is left through radiotherapy combined with chemotherapy. Patients require at least 4-5 weeks to recover after surgery, before starting radiotherapy.
During this recovery period, the remaining cancer cells will continue to grow. The remaining cancer cells that arise are mainly cancer stem cells, and can also become more resistant to radiotherapy and chemotherapy.
In their new approach, the team of researchers added chemotherapy prior to radiotherapy, also called neo-adjuvant chemotherapy.
The neo-adjuvant chemotherapy helped to prevent the tumor from progressing during recovery and increased the patients' survival.
After the neo-adjuvant chemotherapy, the patients were then given accelerated radiotherapy.
"We had better control over the tumor by giving patients the same overall dose of radiotherapy in fewer sessions and a shorter period of time. By doing this, we increased the efficacy of the treatment and we believe that in turn the treatment targeted the stem cells, which are the basis of recurrence. Reducing the radiotherapy sessions by one-third also alleviates the burden for patients. In addition, this represents a considerable cost reduction of delivery of treatment" says Dr. Shenouda.
Additional research is required to validate the findings.
"Fifty per cent of the patients in our study have survived two years since their diagnosis - this is very encouraging and we are very positive about the outcome," says Dr. Shenouda.
The study is published in the International Journal of Radiology Oncology.
- George Shenouda et al. A Phase 2 Trial of Neoadjuvant Temozolomide Followed by Hypofractionated Accelerated Radiation Therapy With Concurrent and Adjuvant Temozolomide for Patients With Glioblastoma. International Journal of Radiology Oncology; (2017) DOI: 10.1016/j.ijrobp.2016.11.006