Kei Ito, Presenter: Nothing to Disclose

Katsuyuki Karasawa, Abstract Co-Author: Nothing to Disclose

Purpose/Objective(s):Stereotactic body radiotherapy (SBRT) for spinal tumors has potentially a strong effect on pain and local control, according to several phase II trials. Patients with oligo-metastasis or who received previous radiation therapy are good candidates for this therapy, but the safety of SBRT for large-volume spinal tumors has not been evaluated. We report our clinical experiences of SBRT for large-volume spinal tumors.Materials/Methods:Although the optimal dose-fraction schedule of SBRT for spinal tumors has not been determined, we have conducted SBRT according to our strategy in which the prescribed doses are 24 Gy in 2 fractions to the spine, 35 Gy in 5 fractions to the other sites than spine and 30 Gy in 5 fractions to a lesion with high risk of radiation injuries. Considering previously delivered radiation dose, we have set the dose limitation of risk organs including spinal cord, small bowel and so on. We conducted SBRT for large-volume spinal tumors among patients with oligo-metastasis and re-irradiated patients.Case 1:A 71-year-old male with oligo-metastasis of the right iliac and sacral bone (PTV; 1,044 cc) from renal cancer. The prescribed dose was 35 Gy in 5 fractions.Case 2:A 79-year-old male with a local recurrence of rectal cancer, invading the sacral bone (PTV; 1,766 cc), which had been previously irradiated twice; 60 Gy in 30 fractions and 8 Gy in 1 fraction. The prescribed dose was 30 Gy in 5 fractions.Case 3:A 39-year-old male with a local recurrence of osteosarcoma invading the 10th - 12th thoracic spine (PTV; 739 cc), which had been irradiated with carbon ion beam of 70.4 GyE in 16 fractions. The spinal cord was irradiated 32 GyE. The lesion had a decompression surgery because of the spinal cord compression. The prescribed dose was 24 Gy in 2 fractions.We evaluated pain control with numeric rating scale (NRS), tumor response with CT or MRI with RECIST criteria, and adverse event with NCI-CTCAE ver.4. The follow-up periods were 5 months/4 months (dead)/4 months in Case 1/2/3, respectively.Results:Pain reduction was achieved in all patients 4 weeks after SBRT (NRS:4 to 0/3 to 1/0 to 0 in Case 1/2/3, respectively) and maintained during 4 month after SBRT. The tumor response 4 weeks after SBRT was Stable Disease (SD)/Progressive Disease/SD in Case 1/2/3, respectively. Grade 1 nausea in case 1, grade 2 radiation dermatitis in case 3, but no grade 3 or greater toxicities were observed.Conclusions:We report our clinical experience of SBRT for large-volume spinal tumors. The clinical trial in our hospital is under preparation to prove the efficacy and safety of SBRT for large-volume spinal tumors.

Ito, K, Karasawa, K, Clinical Experience of Stereotactic Body Radiotherapy for Large-volume Spinal Tumors.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045828.html