Pathological characteristics of spine metastases treated with high-dose single-fraction stereotactic radiosurgery Journal Article


Authors: Katsoulakis, E.; Laufer, I.; Bilsky, M.; Agaram, N. P.; Lovelock, M.; Yamada, Y.
Article Title: Pathological characteristics of spine metastases treated with high-dose single-fraction stereotactic radiosurgery
Abstract: Objective Spine radiosurgery is increasingly being used to treat spinal metastases. As patients are living longer because of the increasing efficacy of systemic agents, appropriate follow-up and posttreatment management for these patients is critical. Tumor progression after spine radiosurgery is rare; however, vertebral compression fractures are recognized as a more common posttreatment effect. The use of radiographic imaging alone posttreatment may make it difficult to distinguish tumor progression from postradiation changes such as fibrosis. This is the largest series from a prospective database in which the authors examine histopathology of samples obtained from patients who underwent surgical intervention for presumed tumor progression or mechanical pain secondary to compression fracture. The majority of patients had tumor ablation and resulting fibrosis rather than tumor progression. The aim of this study was to evaluate tumor histopathology and characteristics of patients who underwent pathological sampling because of radiographic tumor progression, fibrosis, or collapsed vertebrae after receiving high-dose single-fraction stereotactic radiosurgery. Methods Between January 2005 and January 2014, a total of 582 patients were treated with linear accelerator-based single-fraction (18-24 Gy) stereotactic radiosurgery. The authors retrospectively identified 30 patients (5.1%) who underwent surgical intervention for 32 lesions with vertebral cement augmentation for either mechanical pain or instability secondary to vertebral compression fracture (n = 17) or instrumentation (n = 15) for radiographic tumor progression. Radiation and surgical treatment, histopathology, and long-term outcomes were reviewed. Survival and time to recurrence were calculated using the Kaplan-Meier method. Results The mean age at the time of radiosurgery was 59 years (range 36-80 years). The initial pathological diagnoses were obtained for all patients and primarily included radioresistant tumor types, including renal cell carcinoma in 7 (22%), melanoma in 6 (19%), lung carcinoma in 4 (12%), and sarcoma in 3 (9%). The median time to surgical intervention was 24.7 months (range 1.6-50.8 months). The median follow-up and overall survival for all patients were 42.5 months and 41 months (overall survival range 7-86 months), respectively. The majority of assessed lesions showed no evidence of tumor on pathological review (25 of 32, 78%), while a minority of lesions revealed residual tumor (7 of 32, 22%). The median survival for patients after tumor recurrence was 5 months (range 2-70 months). Conc lusions High-dose single-fraction radiosurgery is tumor ablative in the majority of instances. In a minority of cases, tumor persists and salvage treatments should be considered.
Keywords: image-guided radiation therapy; spine stereotactic radiosurgery; tumor ablation; pathological correlation; radiation fibrosis
Journal Title: Neurosurgical Focus
Volume: 42
Issue: 1
ISSN: 1092-0684
Publisher: American Association of Neurological Surgeons  
Date Published: 2017-01-01
Start Page: E7
Language: English
DOI: 10.3171/2016.10.focus16368
PROVIDER: scopus
PUBMED: 28041326
PMCID: PMC5548126
DOI/URL:
Notes: Article -- Export Date: 2 February 2017 -- Source: Scopus
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MSK Authors
  1. Yoshiya Yamada
    479 Yamada
  2. Mark H Bilsky
    319 Bilsky
  3. Narasimhan P Agaram
    190 Agaram
  4. Dale M Lovelock
    183 Lovelock
  5. Ilya Laufer
    146 Laufer