Local control of 1–5 fraction radiotherapy regimens for spinal metastases: an analysis of the impacts of biologically effective dose and primary histology

Abstract

Background This analysis evaluates the impacts of biologically effective dose (BED) and histology on local control (LC) of spinal metastases treated with highly conformal radiotherapy to moderately-escalated doses. Materials and methods Patients were treated at two institutions from 2010–2020. Treatments with less than 5 Gy per fraction or 8 Gy in 1 fraction were excluded. The dataset was divided into three RPA classes predictive of survival (1). The primary endpoint was LC. Results 223 patients with 248 treatments met inclusion criteria. Patients had a median Karnofsky Performance Status (KPS ) of 80, and common histologies included breast (29.4%), non-small cell lung cancer (15.7%), and prostate (13.3%). A median 24 Gy was delivered in 3 fractions (BED: 38.4 Gy) to a median planning target volume (PTV) of 37.3 cc. 2-year LC was 75.7%, and 2-year OS was 42.1%. Increased BED was predictive of improved LC for primary prostate cancer (HR = 0.85, 95% CI: 0.74–0.99). Patients with favorable survival (RPA class 1) had improved LC with BED ≥ 40 Gy (p = 0.05), unlike the intermediate and poor survival groups. No grade 3–5 toxicities were reported. Conclusions Moderately-escalated treatments were efficacious and well-tolerated. BED ≥ 40 Gy may improve LC, particularly for prostate cancer and patients with favorable survival.

Does Timing of Radiation Therapy Impact Wound Healing in Patients Undergoing Metastatic Spine Surgery?

“…Furthermore, the current recommendation is one to five fractions delivering 5-24 Gy per fraction [23], which was adopted at our institution for all patients. A higher dose of radiation may be linked to skin changes, fatigue, radiation induced myelopathy, dysphagia/dysphonia (cervical spine), and GI symptoms (nausea, vomiting, diarrhea, or abdominal cramps) in the thoracic and lumbar spine, among others [23,24].…”

Vertebral hemangioma — the current radiation therapy perspective

“…The most commonly used fractional dose is 1.8–3 Gy and a threshold dose to achieve the control is 34 Gy. Nowadays, SRS and SBRT of the spine is gaining interest and acceptable local control is reported in a study treating spinal tumors with SRS/SBRT [ 46 , 47 ]. A clinical trial is underway to test the efficacy of SBRT for VH for 25 Gy/5# dose regimen and results are awaited [ 48 ].…”