Abstract: External Validity of a Risk Stratification Score Predicting Early Distant Brain Failure and Salvage Whole Brain Radiotherapy after Stereotactic Radiosurgery for Brain Metastases
Robert H. Press
Danielle M. Boselli
James T. Symanowski
Kirtesh R. Patel
Anthony L. Asher
Ashley L. Sumrall
Walter J. Curran Jr.
Hui-Kuo G. Shu
Ian R. Crocker
- Published on the Internal Journal of Radiation Oncology – View Abstract
A scoring system using pre-treatment factors was recently published (Press et al., Cancer 2015) for predicting risk of early (≤6 months) distant brain failure (DBF) and salvage whole brain radiotherapy (WBRT) after stereotactic radiosurgery (SRS) alone. Four risk factors were identified: (1) lack of prior WBRT, (2) melanoma or breast histology, (3) multiple brain metastases, and (4) total volume of brain metastases, International Journal of Radiation Oncology • Biology • Physics (2017), doi: 10.1016/ j.ijrobp.2017.03.012.
We reviewed records of 247 patients with 388 brain metastases treated with SRS between 2010-2013 at Levine Cancer Institute. The Press (Emory) risk score was calculated and applied to the validation cohort population and subsequent risk groups were analyzed using cumulative incidence.
The low risk (LR) group had a significantly lower risk of early DBF compared to high risk (HR) group (22.6% vs. 44%, p=0.004), but there was no difference between the HR and intermediate risk (IR) groups (41.2% vs. 44%, p=0.79). Total lesion volume
The 3 level Emory risk score was shown to not be externally valid, but the model was able to stratify between 2 levels (LR and not-LR (combined IR and HR)] for early (≤6 months) DBF. These results reinforce the importance of validating predictive models in independent cohorts. Further refinement of this scoring system with molecular information and in additional contemporary patient populations is warranted.
Press RH, Boselli DM, Symanowski JT, Lankford SP, McCammon RJ, Moeller BJ, Heinzerling JH, Fasola CE, Burri SH, Patel KR, Asher AL, Sumrall AL, Curran Jr WJ, Shu H-KG, Crocker IR, Prabhu RS, External Validity of a Risk Stratification Score Predicting Early Distant Brain Failure and Salvage Whole Brain Radiotherapy after Stereotactic Radiosurgery for Brain Metastases, International Journal of Radiation Oncology • Biology • Physics (2017), doi: 10.1016/ j.ijrobp.2017.03.012.