Surgical Resection With Radiation Treatment Planning of Spinal Tumors.
Neurosurgery
Radiation dosimetry
Spine
Spine separation surgery
Stereotactic body radiosurgery
Surgery
Treatment planning
Journal
Neurosurgery
ISSN: 1524-4040
Titre abrégé: Neurosurgery
Pays: United States
ID NLM: 7802914
Informations de publication
Date de publication:
01 06 2019
01 06 2019
Historique:
received:
23
10
2017
accepted:
10
04
2018
pubmed:
26
5
2018
medline:
4
6
2020
entrez:
26
5
2018
Statut:
ppublish
Résumé
The clinical paradigm for spinal tumors with epidural involvement is challenging considering the rigid dose tolerance of the spinal cord. One effective approach involves open surgery for tumor resection, followed by stereotactic body radiotherapy (SBRT). Resection extent is often determined by the neurosurgeon's clinical expertise, without considering optimal subsequent post-operative SBRT treatment. To quantify the effect of incremental epidural disease resection on tumor coverage for spine SBRT in an effort to working towards integrating radiotherapy planning within the operating room. Ten patients having undergone spinal separation surgery with postoperative SBRT were retrospectively reviewed. Preoperative magnetic resonance imaging was coregistered to postoperative planning computed tomography to delineate the preoperative epidural disease gross tumor volume (GTV). The GTV was digitally shrunk by a series of fixed amounts away from the cord (up to 6 mm) simulating incremental tumor resection and reflecting an optimal dosimetric endpoint. The dosimetric effect on simulated GTVs was analyzed using metrics such as minimum biologically effective dose (BED) to 95% of the simulated GTV (D95) and compared to the unresected epidural GTV. Epidural GTV D95 increased at an average rate of 0.88 ± 0.09 Gy10 per mm of resected disease up to the simulated 6 mm limit. Mean BED to D95 was 5.3 Gy10 (31.2%) greater than unresected cases. All metrics showed strong positive correlations with increasing tumor resection margins (R2: 0.989-0.999, P < .01). Spine separation surgery provides division between the spinal cord and epidural disease, facilitating better disease coverage for subsequent post-operative SBRT. By quantifying the dosimetric advantage prior to surgery on actual clinical cases, targeted surgical planning can be implemented.
Sections du résumé
BACKGROUND
The clinical paradigm for spinal tumors with epidural involvement is challenging considering the rigid dose tolerance of the spinal cord. One effective approach involves open surgery for tumor resection, followed by stereotactic body radiotherapy (SBRT). Resection extent is often determined by the neurosurgeon's clinical expertise, without considering optimal subsequent post-operative SBRT treatment.
OBJECTIVE
To quantify the effect of incremental epidural disease resection on tumor coverage for spine SBRT in an effort to working towards integrating radiotherapy planning within the operating room.
METHODS
Ten patients having undergone spinal separation surgery with postoperative SBRT were retrospectively reviewed. Preoperative magnetic resonance imaging was coregistered to postoperative planning computed tomography to delineate the preoperative epidural disease gross tumor volume (GTV). The GTV was digitally shrunk by a series of fixed amounts away from the cord (up to 6 mm) simulating incremental tumor resection and reflecting an optimal dosimetric endpoint. The dosimetric effect on simulated GTVs was analyzed using metrics such as minimum biologically effective dose (BED) to 95% of the simulated GTV (D95) and compared to the unresected epidural GTV.
RESULTS
Epidural GTV D95 increased at an average rate of 0.88 ± 0.09 Gy10 per mm of resected disease up to the simulated 6 mm limit. Mean BED to D95 was 5.3 Gy10 (31.2%) greater than unresected cases. All metrics showed strong positive correlations with increasing tumor resection margins (R2: 0.989-0.999, P < .01).
CONCLUSION
Spine separation surgery provides division between the spinal cord and epidural disease, facilitating better disease coverage for subsequent post-operative SBRT. By quantifying the dosimetric advantage prior to surgery on actual clinical cases, targeted surgical planning can be implemented.
Identifiants
pubmed: 29796646
pii: 4996178
doi: 10.1093/neuros/nyy176
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
1242-1250Informations de copyright
Copyright © 2018 by the Congress of Neurological Surgeons.