World neurosurgery | 2019
Comparison of clinical outcomes based on target delineation in patients treated with stereotactic body radiotherapy (SBRT) for spinal metastases.
Abstract
OBJECTIVE\nStereotactic body radiotherapy (SBRT) is an effective treatment for spinal metastases in the vertebral body. There is variation between practitioners about appropriate target delineation. As such, we compare tumor control, rates of compression fracture, and pain control for patients treated with stereotactic body radiotherapy (SBRT) for spinal metastases treated to lesion only (LO) versus the full vertebral body (FVB).\n\n\nMETHODS\n126 spinal metastases in 84 patients were treated with single-fraction stereotactic body radiotherapy between January 2009 to February 2015. There were 36 lesions (29%) were treated with radiation to the FVB, and the remainder were treated to the LO. Radiation plans were reviewed to determine the treatment volume. Odds ratios were used to compare rates of compression fracture and local failure. Regression analysis was performed to identify predictors of outcome.\n\n\nRESULTS\nThere were five failures in the FVB group and 14 in the LO group, but this was not statistically significant (p = 0.5). There was no difference in pain reduction between groups (p = 0.9). There were seven post-treatment compression fractures in the LO group and four in the FVB group, this difference did not reach statistical significance (p = 0.6). Minimum dose to PTV, age, and PTV size were the only significant factors predicting local failure, vertebral body fracture, and pain control respectively.\n\n\nCONCLUSIONS\nGiven that we found no difference in tumor control, pain reduction and fracture rate between patients treated to the FVB vs. LO, it may be reasonable to consider treating with SBRT to the LO in select patients.