ESTRO 2024 - Abstract Book

S1959

Clinical - Mixed sites, palliation

ESTRO 2024

Stereotactic Body Radiation Therapy (SBRT) for pain control in spinal metastases

Beatrice Bettazzi 1 , Maria G Carnevale 1 , Victoria Lorenzetti 1 , Mauro Loi 1 , Gabriele Simontacchi 1 , Lucia Angelini 1 , Anna Peruzzi 1 , Viola Salvestrini 1 , Pierluigi Bonomo 1 , Monica Mangoni 1 , Vanessa Di Cataldo 1 , Isacco Desideri 1 , Icro Meattini 1 , Giulio Francolini 1 , Emanuela Olmetto 1 , Pietro Garlatti 1 , Raffaella Doro 2 , Laura Masi 2 , Ivano Bonucci 2 , Lorenzo Livi 1 1 Radiation Oncology, Azienda Ospedaliero Universitaria Careggi, Università di Firenze, Firenze, Italy. 2 CyberKnife Center, Istituto Fiorentino di Cura e Assistenza (IFCA), Firenze, Italy

Purpose/Objective:

Despite evidence from recent prospective trials [1;2], Stereotactic Body Radiation Therapy (SBRT) is not yet recognized as a standard of care for antalgic purposes. We therefore analyzed pain control after SBRT on spinal metastases.

Material/Methods:

We retrospectively collected data on palliative SBRT, performed at our center between 2021 and 2022 on a cohort of consecutive patients. SBRT was delivered both with Volumetric Modulated Arc Therapy (VMAT) using a C-arm Linac and robotic-arm radiotherapy (rRT) using spine tracking. All SBRT treatments were performed on secondary bone lesions from primary tumors of miscellaneous histology. An alpha/beta of 10 was assumed to calculate biologically effective dose (BED) for dose regimens comparison. Pain control and adverse events were assessed using the CTCAE v. 5 score. χ² test was used to compare categorical values to correlate pain control with clinical and treatment related data.

Results:

Among 226 spinal metastases treated with SBRT, 72 were performed for antalgic purpose. Pain control data were available for 63 of these. Treatment sites were cervical, thoracic and lumbosacral spine in respectively 2, 37, 24 cases. Oligometastatic disease was found in 18 cases. SBRT was carried out with rRT or VMAT in 35 and 28 cases respectively. Treatment schedules were 24 Gy in 2 fractions (n=32) or 27-30 Gy in 3 fractions (n=31), with a median BED of 52.8 Gy (range 51.3-60). At a median follow-up of 10 months, pain response was achieved in 38 patients, consisting of complete pain relief in 28 cases and partial response in 10. Stability of the symptom was obtained in 24 patients. Only 1 patient experienced increased pain after treatment, possibly in relation with vertebral fracture detected after radiologic review. We show our results in Figure 1 . Pain flare was observed in 11 patients, while G ≥ 2 nausea/vomit was observed in 3 patients. No difference in terms of pain control and pain flare was observed according to treatment schedule, technique and location.

Figure 1.