International journal of radiation oncology, biology, physics 2018-01-31
Head and Neck Tumor Control Probability: Radiation Dose-Volume Effects in Stereotactic Body Radiation Therapy for Locally Recurrent Previously-Irradiated Head and Neck Cancer: Report of the AAPM Working Group.
Abstract
Purpose
Stereotactic body radiation therapy (SBRT) has emerged as a viable reirradiation strategy for locally recurrent previously-irradiated head and neck cancer. Doses in the literature have varied, which challenges clinical application of SBRT as well as clinical trial design.
Material & methods
A working group was formed through the American Association of Physicists in Medicine to study tumor control probabilities for SBRT in head and neck cancer. We herein present a systematic review of the available literature addressing the dose/volume data for tumor control probability with SBRT in patients with locally recurrent previously-irradiated head and neck cancer. Dose-response models are generated that present tumor control probability as a function of dose.
Results
Data from more than 300 cases in 8 publications suggest that there is a dose-response relationship, with superior local control and possibly improved overall survival for doses of 35 to 45 Gy (in 5 fractions) compared with <30 Gy.
Conclusion
Stereotactic body radiation therapy doses equivalent to 5-fraction doses of 40 to 50 Gy are suggested for retreatment.
Related Questions
What approach do you take to determine dose constraints for SBRT reirradiation of the head and neck?
There is likely no "safe" dose when delivering full-dose SBRT overlapping tissue that previously received 40-70 Gy. The best you can do is make sure the patient understands the risks, that this strategy fits their goals of care, that you've considered all alternatives, and that you approach planning...
Do you give Cetuximab concurrently with SBRT for recurrent head and neck cancers previous treated with definitive radiation?
This is an area of active clinical trial development esp. as it relates to immunotherapy concurrent with SBRT. That being said, we certainly have phase I, II, and preliminary phase III data suggesting that SBRT in the setting of recurrent disease is safe and may offer extended LR control rates in a ...