BACKGROUND: Vertebral compression fracture (VCF) is a challenging and not infrequent complication observed following spine stereotactic body radiation therapy (SBRT). OBJECTIVE: To summarize the data from the multiple studies that have been published, addressing the risk and predictive factors for VCF post-SBRT. METHODS: A systematic literature review was conducted. Studies were selected if they specifically addressed risk factors for post-SBRT VCF in their analyses. RESULTS: A total of 11 studies were identified, reporting both the risk of VCF post-SBRT and an analysis of risk factors based on univariate and multivariate analysis. A total of 2911 spinal segments were treated with a crude VCF rate of 13.9%. The most frequently identified risk factors on multivariate analysis were: lytic disease (hazard ratio [HR] range, 2.76-12.2), baseline VCF prior to SBRT (HR range, 1.69-9.25), higher dose per fraction SBRT (HR range, 5.03-6.82), spinal deformity (HR range, 2.99-11.1), older age (HR range, 2.15-5.67), and more than 40% to 50% of vertebral body involved by tumor (HR range, 3.9-4.46). In the 9 studies that specifically reported on the use of post-SBRT surgical procedures, 37% of VCF had undergone an intervention (range, 11%-60%). CONCLUSION: VCF is an important adverse effect following SBRT. Risk factors have been identified to guide the selection of high-risk patients. Evidence-based algorithms with respect to patient selection and intervention are needed.

BACKGROUND: Postoperative stereotactic body radiotherapy (pSBRT) is an emerging indication for spinal metastases (SM). OBJECTIVE: To report our experience with pSBRT for SM. METHODS: A retrospective chart review was performed for prospectively collected data of patients treated between September 2008 to December 2015 with pSBRT and followed with serial spinal MRIs every 2 to 3 mo until death or last follow-up. Univariate and multivariable analyses were performed to identify predictive factors. RESULTS: A total of 83 spinal segments in 47 patients treated with a median dose of 24 Gy in 2 fractions were included, with mostly lung and breast primaries. A total of 59.3% had preoperative high-grade epidural disease (ED) and 39.7% were unstable. The 12-mo cumulative incidence of local failure was 17% for all segments, and 33.3%, 21.8%, and 0% in segments with postoperative high-grade, low-grade, and no ED, respectively. Downgrading preoperative ED was predictive of better local control (P = .03). The grade of postoperative ED was also predictive for local control (P < .0001), as was a longer interval between prior radiotherapy and pSBRT in those previously irradiated (P = .004). The 12-mo overall survival rate was 55%. One case of radiculopathy, 3 vertebral compression fractures, and no cases of myelopathy, hardware failure, or skin breakdown were observed. CONCLUSION: pSBRT is an effective and safe treatment. The association between downgrading preoperative ED and better local control following pSBRT is confirmed and supports the concept of separation surgery.

Patients with oral cavity cancers often present late to seek medical care. Surgery is usually the preferred upfront treatment. However, surgical resection cannot be achieved in many cases with advanced disease without major impact on patient’s quality of life. On the other hand, radiotherapy (RT) and chemotherapy (CT) have not been employed routinely to replace surgery as curative treatment or to facilitate surgery as neoadjuvant therapy. The optimal care of these patients is challenging when surgical treatment is not feasible. In this review, we aimed to summarize the best available evidence-based treatment approaches for patients with locally advanced oral cavity cancer. Surgery followed by RT with or without CT is the standard of care for locally advanced oral cavity squamous cell carcinoma. In the case of unresectable disease, induction CT prior to surgery or chemoradiotherapy (CRT) can be attempted with curative intent. For inoperable patients or when surgery is expected to result in poor functional outcome, patients may be candidates for possibly curative CRT or palliative RT with a focus on quality of life.

Purpose: Two dose calculation algorithms are available in Varian Eclipse software: Anisotropic Analytical Algorithm (AAA) and Acuros External Beam (AXB). Many Varian Eclipse‐based centers have access to AXB; however, a thorough understanding of how it will affect plan characteristics and, subsequently, clinical practice is necessary prior to implementation. We characterized the difference in breast plan quality between AXB and AAA for dissemination to clinicians during implementation.Methods: Locoregional irradiation plans were created with AAA for 30 breast cancer patients with a prescription dose of 50 Gy to the breast and 45 Gy to the regional node, in 25 fractions. The internal mammary chain (IMC_CTV) nodes were covered by 80% of the breast dose. AXB, both dose‐to‐water and dose‐to‐medium reporting, was used to recalculate plans while maintaining constant monitor units. Target coverage and organ‐at‐risk doses were compared between the two algorithms using dose–volume parameters. An analysis to assess location‐specific changes was performed by dividing the breast into nine subvolumes in the superior–inferior and left–right directions.Results: There were minimal differences found between the AXB and AAA calculated plans. The median difference between AXB and AAA for breast_CTV V_95%, was <2.5%. For IMC_CTV, the median differences V_95%, and V_80% were <5% and 0%, respectively; indicating IMC_CTV coverage only decreased when marginally covered. Mean superficial dose increased by a median of 3.2 Gy. In the subvolume analysis, the medial subvolumes were “hotter” when recalculated with AXB and the lateral subvolumes “cooler” with AXB; however, all differences were within 2 Gy.Conclusion: We observed minimal difference in magnitude and spatial distribution of dose when comparing the two algorithms. The largest observable differences occurred in superficial dose regions. Therefore, clinical implementation of AXB from AAA for breast radiotherapy is not expected to result in changes in clinical practice for prescribing or planning breast radiotherapy.

Spine is a common site of metastases in cancer patients. Spine surgery is indicated for select patients, typically those with mechanical instability and/or malignant epidural spinal cord (or cauda equina) compression. Although post-operative conventional palliative external beam radiation therapy has been the standard of care, technical improvements in radiation planning and image-guided radiotherapy have allowed for the application of stereotactic body radiotherapy (SBRT) to the spine. Spine SBRT is intended to ablate residual tumor and optimize local control by delivering several fold greater biologically effective doses. Early clinical experience of postoperative spinal SBRT report encouraging results in terms of safety and efficacy. In this review, we summarize the clinical and technical aspects pertinent to a safe and effective practice of postoperative SBRT for spinal metastases.