How would you approach treatment of an unresectable paraspinal chondrosarcoma causing cord compression?

For unresectable chondrosarcoma, RT is usually recommended. If conventional fractionated regimens (1.8-2 Gy per fraction) are used, RT of over 70 Gy will be needed to control the disease (per NCCN). In recent years, a limited number of published studies evaluated SBRT (5 fractions) for chondrosarcoma (where chordoma is usually included in the study). A dose of 25-40 Gy (a median dose of 37.5 Gy) has been used to achieve a local control rate of over 80%. So if the mass is less than 5 cm, I prefer to use SBRT technique with a dose of up to 40 Gy in 5 fractions.

It is more challenging when paraspinal chondrosarcoma is causing cord compression. If the conventional fractionated regimen is used, I will use IMRT to treat the initial field (without...

The first step in the treatment of an unresectable paraspinal chondrosarcoma is to relieve the cord compression by surgery. The next step is to stabilize the spine. It would be worthwhile to get an opinion regarding additional surgery from a center that specializes in surgery involving disorders of the spine to ensure that this is not a truly unresectable lesion. The optimal form of adjuvant treatment in my opinion is to use the pencil beam scanning proton therapy using the IMPT technique. This would allow a target dose of a minimum of 70 Gy in 35 fractions to be delivered to the tumor while keeping the cord to within tolerance limits (with virtually no dose to the bowel space) as demonstrated from the experience of the Paul Scherrer Instit...