Stereotactic radiosurgery for intracranial chordomas: an international multiinstitutional study

Abstract

OBJECTIVE The object of this study was to evaluate the safety, efficacy, and long-term outcomes of stereotactic radiosurgery (SRS) in the management of intracranial chordomas. METHODS This retrospective multicenter study involved consecutive patients managed with single-session SRS for an intracranial chordoma at 10 participating centers. Radiological and neurological outcomes were assessed after SRS, and predictive factors were evaluated via statistical methodology. RESULTS A total of 93 patients (56 males [60.2%], mean age 44.8 years [SD 16.6]) underwent single-session SRS for intracranial chordoma. SRS was utilized as adjuvant treatment in 77 (82.8%) cases, at recurrence in 13 (14.0%) cases, and as primary treatment in 3 (3.2%) cases. The mean tumor volume was 8 cm3 (SD 7.3), and the mean prescription volume was 9.1 cm3 (SD 8.7). The mean margin and maximum radiosurgical doses utilized were 17 Gy (SD 3.6) and 34.2 Gy (SD 6.4), respectively. On multivariate analysis, treatment failure due to tumor progression (p = 0.001) was associated with an increased risk for post-SRS neurological deterioration, and a maximum dose > 29 Gy (p = 0.006) was associated with a decreased risk. A maximum dose > 29 Gy was also associated with improved local tumor control (p = 0.02), whereas the presence of neurological deficits prior to SRS (p = 0.04) and an age > 65 years at SRS (p = 0.03) were associated with worse local tumor control. The 5- and 10-year tumor progression-free survival rates were 54.7% and 34.7%, respectively. An age > 65 years at SRS (p = 0.01) was associated with decreased overall survival. The 5- and 10-year overall survival rates were 83% and 70%, respectively. CONCLUSIONS SRS appears to be a safe and relatively effective adjuvant management option for intracranial chordomas. The best outcomes were obtained in younger patients without significant neurological deficits. Further well-designed studies are necessary to define the best timing for the use of SRS in the multidisciplinary management of intracranial chordomas.

Adjuvant stereotactic radiosurgery with or without postoperative fractionated radiation therapy in adults with skull base chordomas: a systematic review

“…Such doses are considerably higher than those needed to control skull base meningiomas or schwannomas. [38][39][40][41] Additionally, in a recent multicenter study, Pikis et al 42 investigated the impact of SRS on chordomas and found that a marginal dose > 17 Gy had a protective value in the univariate analysis but not the multivariate analysis. These authors also found that a maximal dose > 29 Gy provided a 24% decrease in the likelihood of neurological deterioration and a 40% decrease in the likelihood of tumor progression.…”

Proton and carbon ion beam treatment with active raster scanning method in 147 patients with skull base chordoma at the Heidelberg Ion Beam Therapy Center—a single-center experience

“…A recent analysis of 93 patients with small intracranial chordoma who underwent single-session SRS has been published by Pikis et al. [ 24 ] With a mean maximum dose of 34.2 Gy, the LC after 5 years was 54.7%. Notably, the irradiation volume was much smaller than in the prevailing study (mean 8 cc vs. 40.4 cc).…”

Adjuvant Stereotactic Radiosurgery With or Without Postresection Fractionated Radiation Therapy for the Management of Clival Chordomas in Adults: An International Multicenter Case Series

“…Detailed methods of the study, SRS techniques, and follow-up protocol have been previously defined. 18 Institutional review board approval and patient consents were obtained in all centers for all included patients. The present article, conducted according to the PROCESS guidelines, 19 is a subgroup analysis limited to histologically proven-with brachyury-positive staining-primary clival chordomas in adults.…”

“…Recently, we published an international multi-institutional study of 93 clival chordomas treated with SRS at 10 participating centers. 18 The report examined the impact of chordoma SRS for various indications—primary SRS without resection, adjuvant SRS after resection, boost SRS after FRT, and salvage SRS after recurrence. Data are available on reasonable request.…”