ESTRO 2024 - Abstract Book

S737

Clinical - CNS

ESTRO 2024

40

Digital Poster

Re-irradiation of stereotactic body radiotherapy for metastatic epidural spinal cord compression

Yutaro Koide 1 , Shouichi Haimoto 2 , Hidetoshi Shimizu 1 , Takahiro Aoyama 1 , Yurika Shindo 1 , Naoya Nagai 1 , Shingo Hashimoto 1 , Hiroyuki Tachibana 1 , Takeshi Kodaira 1 1 Aichi Cancer Center Hospital, Radiation Oncology, Aichi, Japan. 2 Aichi Cancer Center Hospital, Neurosurgery, Aichi, Japan

Purpose/Objective:

This study aimed to evaluate the outcomes of re-irradiation with 24 Gy in 2 fractions stereotactic body radiotherapy (SBRT) for metastatic epidural spinal cord compression (MESCC) in the cervical and thoracic spine previously irradiated with more than 50 Gy.

Material/Methods:

We retrospectively reviewed 21 patients treated with re-irradiation SBRT for MESCC between April 2018 and March 2023, who had a history of irradiation to the target vertebrae exceeding 50 Gy. Overall survival (OS), local control (LC), and treatment-related adverse events were assessed.

Results:

The median age was 68 years. The primary tumor site was esophageal in 6 patients, lung in 6, head and neck in 7, and others in 2. The 1-year overall survival rate was 57.3%. Local recurrence occurred in 6 patients (29%), with 1 year and 2-year recurrence rates of 22% and 31% respectively. Treatment-related mortality occurred in 1 patient due to mediastinitis and epidural abscess from esophageal perforation. Other toxicities included 5 cases of vertebral fractures (3 at the time of recurrence) and 1 case of radiation pneumonitis (Grade 2).

Conclusion:

Re-irradiation with 24 Gy in 2 fractions SBRT may be an effective salvage treatment for selected patients with cervical and thoracic spine metastases previously irradiated with more than 50 Gy. Careful consideration of surrounding organs at risk, especially the esophagus, laryngopharynx, and carotid artery is critical.

Keywords: spine, SBRT, re-irradiation,