Quantifying the changes in the tumour vascular micro-environment in spinal metastases treated with stereotactic body radiotherapy - a single arm prospective study

Vascular changes in spine metastases treated with SBRT

Authors

  • Balamurugan A Vellayappan National University Cancer Institute, National University Health System, National University of Singapore
  • Dennis Cheong Clinical Imaging Research Centre, National University of Singapore
  • Salil Singbal Department of Diagnostic Imaging, National University Hospital, Singapore
  • Jeremy Tey Department of Radiation Oncology, National University Cancer Institute Singapore, National University Hospital, Singapore
  • Yu Yang Soon Department of Radiation Oncology, National University Cancer Institute Singapore, National University Hospital, Singapore
  • Cheng Nang Leong Department of Radiation Oncology, National University Cancer Institute Singapore, National University Hospital, Singapore
  • Alvin Wong Department of Haematology-Oncology, National University Cancer Institute Singapore, National University Hospital, Singapore
  • Sein Lwin Division of Neurosurgery, Department of Surgery, National University Hospital, Singapore
  • Chau Hung Lee Department of Radiology, Tan Tock Seng Hospital, Singapore
  • Pravin Periasamy Centre for Life Sciences(CeLS), National University of Singapore
  • Simon Lo Department of Radiation Oncology, University of Washington, Seattle, WA, USA
  • Naresh Kumar Department of Orthopaedic Surgery, National University Hospital, Singapore

Abstract

Objectives The primary objective is to quantify changes in vascular micro-environment in spinal metastases(SM) patients treated with SBRT with multi-parametric dynamic contrast enhanced(DCE) magnetic resonance imaging (MRI). The secondary objective is to study plasma biomarkers related to endothelial apoptosis.

 

Methods

Patients were imaged with DCE-MRI at baseline/1-week/12-weeks post-SBRT. Metrics including normalised time-dependent leakage(Ktrans), permeability surface product(PS), fractional plasma volume(Vp), extracellular volume(Ve) and perfusion(F) were estimated using distributed parameter model. Serum acid sphingomyelinase(ASM) and sphingosine-1-phosphate(S1P) were quantified using ELISA. Clinical outcomes including physician-scored and patient-reported toxicity were collected.

 

Results

Twelve patients (with varying primary histology) were recruited, of whom 10 underwent SBRT. Nine patients (with 10 lesions) completed all 3 imaging assessment timepoints. One patient died due to pneumonia (unrelated) before follow-up scans were performed. Median SBRT dose 27 Gy(range:24–27) over 3 fractions(range:2–3). Median follow-up for alive patients was 42-months(range:22.3–54.3), with a local control of 90% and one grade 2 or higher toxicity (vertebral compression fracture). In general, we found an overall trend of reduction at 12-weeks in all parameters(Ktrans/PS/Vp/Ve/F). Ktrans and PS showed a reduction as early as 1-week. Ve/Vp/F exhibited a slight rise 1-week post-SBRT before reducing below the baseline value. There were no significant changes, post-SBRT, in plasma biomarkers(ASM/S1P).

 

Conclusion

Tumour vascular micro-environment (measured by various metrics) showed a general trend towards downregulation post-SBRT. It is likely that vascular-mediated cell killing contributes to excellent local control rates seen with SBRT. Future studies should evaluate the effect of SBRT on primary-specific spinal metastases (e.g., renal cell carcinoma).

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Published

2022-12-05

How to Cite

Vellayappan, B. A., Cheong, D. ., Singbal, S., Tey, J. ., Soon, Y. Y., Leong, C. N., Wong, A., Lwin, S., Lee, C. H., Periasamy, P., Lo, S., & Kumar, N. (2022). Quantifying the changes in the tumour vascular micro-environment in spinal metastases treated with stereotactic body radiotherapy - a single arm prospective study : Vascular changes in spine metastases treated with SBRT . Radiology and Oncology, 56(4), 525–534. Retrieved from https://radioloncol.com/index.php/ro/article/view/3959

Issue

Section

Clinical oncology