International journal of radiation oncology, biology, physics 2016-10-01
Stereotactic Radiosurgery for Brainstem Metastases: An International Cooperative Study to Define Response and Toxicity.
ABSTRACT
PURPOSE
To pool data across multiple institutions internationally and report on the cumulative experience of brainstem stereotactic radiosurgery (SRS).
METHODS AND MATERIALS
Data on patients with brainstem metastases treated with SRS were collected through the International Gamma Knife Research Foundation. Clinical, radiographic, and dosimetric characteristics were compared for factors prognostic for local control (LC) and overall survival (OS) using univariate and multivariate analyses.
RESULTS
Of 547 patients with 596 brainstem metastases treated with SRS, treatment of 7.4% of tumors resulted in severe SRS-induced toxicity (grade ≥3, increased odds with increasing tumor volume, margin dose, and whole-brain irradiation). Local control at 12 months after SRS was 81.8% and was improved with increasing margin dose and maximum dose. Overall survival at 12 months after SRS was 32.7% and impacted by age, gender, number of metastases, tumor histology, and performance score.
CONCLUSIONS
Our study provides additional evidence that SRS has become an option for patients with brainstem metastases, with an excellent benefit-to-risk ratio in the hands of experienced clinicians. Prior whole-brain irradiation increases the risk of severe toxicity in brainstem metastasis patients undergoing SRS.
Related Questions
New comment by Radiation Oncologist at Mallory Radiotherapy, PLLC ( March 4, 2020)
How would you recommend treating a small (3-4 mm) melanoma met in the brainstem when using LINAC-based SRS (VMAT planning)? What dose fractionation would you use and PTV margi...
What factors influence your choice of SRS vs more fractionated regimens?
New comment by Radiation Oncologist at Mercy Health Johnson Family Cancer Center ( April 14, 2023)
Is there a size where you would consider a more fractionated regimen?
Do you treat on consecutive days or more protracted interfraction intervals? Does tumor type (benign vs malignant) or size influence your choice?
New comment by Radiation Oncologist at Vanderbilt-Ingram Cancer Center ( July 5, 2022)
I generally do 27/3 every other day. If I was doing 30Gy in 5, I would do daily.
When do you decrease your SRS dose or consider fractionated SRS regimens?
New comment by Radiation Oncologist at Roswell Park Comprehensive Cancer Center ( July 17, 2020)
Calculate standard SRS dose and discount by 2Gy for deep thalamus. Go for steepest dose gradient outside tumor possible. Watch for internal capsule,