Abstract | BACKGROUND: For metastatic spinal cord compression (MSCC), conventional radiotherapy with 10 × 3 Gy in 2 weeks results in better local progression-free survival (LPFS) than 5 × 4 Gy in 1 week. Since patients with MSCC are often significantly impaired, an overall treatment time of 1 week would be preferable if resulting in similar outcomes as longer programs. This may be achieved with 5 × 5 Gy in 1 week, since the biologically effective dose is similar to 10 × 3 Gy. It can be expected that 5 × 5 Gy (like 10 × 3) Gy results in better LPFS than 5 × 4 Gy in 1 week. METHODS/DESIGN: This phase 2 study investigates LPFS after high-precision RT with 5 × 5 Gy in 1 week. LPFS is defined as freedom from both progression of motor deficits during RT and new or progressive motor deficits dur to an in-field recurrence of MSCC following RT. Considering the tolerance dose of the spinal cord, 5 × 5 Gy can be safely administered with high-precision radiotherapy such as volumetric modulated arc therapy (VMAT) or stereotactic body radiotherapy (SBRT). Maximum dose to the spinal cord should not exceed 101.5% of the prescribed dose to keep the risk of radiation myelopathy below 0.03%. Primary endpoint is LPFS at 6 months following radiotherapy; secondary endpoints include motor function/ability to walk, sensory function, sphincter dysfunction, LPFS directly and 1 and 3 months following radiotherapy, overall survival, pain relief, quality of life and toxicity. Follow-up visits will be performed directly and at 1, 3 and 6 months following radiotherapy. After completion of this phase 2 study, patients will be compared to a historical control group receiving conventional radiotherapy with 5 × 4 Gy in 1 week. Forty-four patients will be included assuming 5 × 5 Gy will provide the same benefit in LPFS when compared to 5 × 4 Gy as reported for 10 × 3 Gy. DISCUSSION: If superiority regarding LPFS is shown for high-precision radiotherapy with 5 × 5 Gy when compared to conventional radiotherapy with 5 × 4 Gy, patients with MSCC would benefit from 5 × 5 Gy, since high LPFS rates could be achieved with 1 week of radiotherapy instead of 2 weeks (10 × 3 Gy). TRIAL REGISTRATION: clinicaltrials.gov NCT03070431 . Registered 27 February 2017.
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Authors | Dirk Rades, Jon Cacicedo, Antonio J Conde-Moreno, Claudia Doemer, Jürgen Dunst, Darejan Lomidze, Barbara Segedin, Denise Olbrich, Niels Henrik Holländer |
Journal | BMC cancer
(BMC Cancer)
Vol. 17
Issue 1
Pg. 818
(Dec 04 2017)
ISSN: 1471-2407 [Electronic] England |
PMID | 29202720
(Publication Type: Journal Article)
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Topics |
- Clinical Trials, Phase II as Topic
- Disease-Free Survival
- Dose Fractionation, Radiation
- Humans
- Motor Disorders
(etiology, therapy)
- Multicenter Studies as Topic
- Radiotherapy Planning, Computer-Assisted
- Spinal Cord Compression
(complications, radiotherapy)
- Spinal Neoplasms
(radiotherapy, secondary)
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