Prophylactic dexamethasone effectively reduces the incidence of pain flare following spine stereotactic body radiotherapy (SBRT): a prospective observational study.

Purpose: The purpose of this study was to determine the incidence of pain flare (PF) in patients receiving spine stereotactic body radiotherapy (SBRT) treated with prophylactic oral dexamethasone (DEX) 1 h before and for 4 days following SBRT.

Methods: Forty-seven patients were accrued on this prospective observational study. The first cohort of 24 patients was treated with 4 mg, while a second cohort of 23 patients treated with 8 mg of DEX. The Brief Pain Inventory (BPI) was used to score pain and functional interference each day during SBRT and for 10 days following. Comparisons between the 4 and 8 mg cohorts, in addition to our previously reported steroid naïve patients post SBRT (n = 41), were also performed.

Results: The total incidence of PF was 19 % (9/47). The incidence in the 4 and 8 mg cohorts was 25 % (6/24) and 13 % (3/23), respectively, and the difference was not statistically significant (p = 0.46). Comparing functional interference, the 4 mg cohort had better profile in walking ability (p < 0.005) and relationships with others (p < 0.035) compared to the 8 mg cohort. Compared to our previously reported steroid naïve cohort, prophylactic DEX significantly reduced the incidence of PF (68 vs. 19 %, p < 0.0001, respectively), patients had lower worst pain scores, and improved general activity interference outcome.

Conclusion: We recommend prophylactic DEX for patients treated with spine SBRT. Our current practice is based on the 4 mg protocol primarily due to the improved functional interference outcomes. A randomized trial is required to finalize the optimal regimen and schedule.