Spinal cord compression

12. Oct 2016
High-precision radiotherapy of motor deficits due to metastatic spinal cord compression

Spinal cord compression and its treatment
Metastatic spinal cord compression (MSCC) occurs in five to ten percent of all cancer patients during the course of their disease. Untreated, this can lead to a complete paraplegia. Radiotherapy alone is the most common treatment. However, various radiation concepts (regime) are available. Longer-course radiotherapy programs result in better local progression-free survival (LPFS) than short-course programs. The advantage is attributed to the higher biological effect of the long-term therapy.

Aim is to reduce treatment time
The biological effect of radiotherapy depends on both the total dose and the dose per session (fraction) and is described by the equivalent dose (EQD2: Equivalent dose in two Gy fractions) in gray (GY). The aim of this study is the execution of five fractions, where a higher dose per session is given. The EQD2 of this regime is similar to the EQD2 of a long-term therapy. This treatment concept –is expected to result in a shorter overall treatment time being more convenient for the patients.

Use of modern high-precision techniques in radiotherapy
Radiotherapy of MSCC can be intensified with the use of high-precision techniques such as volumetric modulated arc therapy (VMAT) and stereotactic body radiotherapy (SBRT) considering the tolerance doses of the spinal cord and the vertebral bone in order to avoid the risk of radiation myelopathy and damage to the vertebral bone.

Course of the study
In this phase II study, 44 patients with MSCC will get included receiving treatment with high-precision radio therapy. The primary aim is to investigate the LPFS of MSCC after six months. In addition, motor function/ability to walk, pain, quality of life, toxicity and overall survival are examined. The results are compared with those of patients from the world's largest MSCC database who received standard short-course radiotherapy with 5x4 Gy.

Objectives
It is expected that high-precision radiotherapy in one week results in significantly better LPFS of MSCC than conventional short-course treatment in one week. As a result, the high-precision radiotherapy could be a preferable alternative to short-course radiotherapy with 5x4 Gy in one week and longer-course radiotherapy with 10x3 Gy in two weeks.

Coordinating Investigator
Prof. Dr. med. Dirk Rades, Department of Radiation Oncology, University of Lübeck / University Medical Center Schleswig-Holstein Campus Lübeck (Germany)