Fracture Risk Following Lumbosacral Spine SBRT in Patients Having Received Previous Whole Pelvis Radiation Therapy

PURPOSE/OBJECTIVE(S)

Stereotactic body radiation therapy (SBRT) for metastatic spinal disease provides local control with palliative effects1. Previous studies have demonstrated a posttreatment fracture rate range of roughly 5.7-39%2, with 14-17% the most commonly cited fracture risk range. However, the rate of spine fracture after lumbosacral SBRT in patients having received prior pelvic radiation therapy (RT) is unclear. The purpose of this study is to investigate the incidence of fracture in patients receiving lumbosacral spine SBRT following previous whole pelvic RT.

MATERIALS/METHODS

This study was a single institution retrospective chart review. All lumbar and sacral spine SBRT cases over a 5-year period (from January 2018 through September 2022) with at least three months of post-treatment follow-up were identified. Patients having previously received pelvic RT were assessed; the development of a vertebral fracture was recorded as was the time to fracture and potential intervention (if any).

RESULTS

A total of 35 lumbosacral spine SBRT cases were identified. Of those eight (23%) previously received whole pelvic RT, ranging from 20-70 Gy/5-35 fractions. Of the lumbosacral spine SBRT patients having received prior pelvic RT, two (25%) developed a fracture post-treatment. The average time to fracture was 7.5 months. Both fractures were treated with conservative management; neither required vertebroplasty/kyphoplasty or operative stabilization. The mean dose per SBRT fraction for patients who suffered a fracture (8.5 Gy) did not significantly differ from that for patients who did not suffer a fracture (9 Gy).

CONCLUSION

In the first examination of lumbosacral fracture risk following SBRT to patients having received previous pelvic RT, the fracture rate in this patient population was 25%. Noteworthy is that the SBRT dose per fraction did not differ between patients having suffered a fracture versus those without fracture. These findings indicate that patients having received previous whole pelvis RT should be counseled on the potential increased risk of fracture; however, there is no evidence that decreasing SBRT dose per fraction reduces the likelihood of fracture in this patient population. This increased fracture rate is of concern, and further investigation in larger studies to identify potential risk factors for vertebral fracture such as systemic therapy, age and gender is warranted.

Assessment of patient-reported outcome and quality of life improvement following surgery for epiphora

PurposeTo assess and compare the subjective improvement in symptoms and quality of life in adult patients who underwent commonly performed oculoplastic surgical interventions to treat epiphora.Materials and methodsA prospective study was undertaken involving all adult patients undergoing dacryocystorhinostomy (DCR), lid tightening (lateral tarsal strip or lateral wedge resection), and punctoplasty surgery at our institution. We assessed severity of epiphora preoperatively using the Munk score. At 3 months postoperatively, all patients were sent postal questionnaires comprising of Munk score, 'social impact score' from validated Lac-Q questionnaire ranging from 0 (no impact) to 5 (maximal negative impact) and Glasgow Benefit Inventory (GBI) score, ranging from -100 (maximal detriment) to +100 (maximal benefit).ResultsA total of 134 questionnaires were sent with an overall response rate of 74.6%. For the purpose of data analysis, patients were divided into four groups: DCR, lid tightening, punctoplasty, and combined group (lid tightening plus punctoplasty). There was statistically significant improvement in subjective epiphora postoperatively, as assessed by Munk score (P<0.001) in all groups. The total GBI scores were +42.67 (95% CI: 33.42-51.91) for DCR, +19.65 (95% CI: 10.33-28.97) for lid tightening, +16.06 (95% CI: 2.65-29.48) for punctoplasty, and +26.53 (95% CI: 13.15-39.90) for the combined group, demonstrating a positive change in health status for all groups. There was negative correlation between total GBI and post-operative Munk scores (r=-0.58, P<0.001), and positive correlation between Lac-Q and Munk scores (r=0.65, P<0.001).ConclusionPatients derived significant improvement in symptoms and health-related quality of life benefit following all surgical interventions for epiphora.