Incidence, Treatment, and Survival Patterns for Sacral Chordoma in the United States, 1974-2011.
BACKGROUND
Sacral chordomas represent one half of all chordomas, a rare neoplasm of notochordal remnants. Current NCCN guidelines recommend surgical resection with or without adjuvant radiotherapy or definitive radiation for unresectable cases. Recent advances in radiation for chordomas include conformal photon and proton beam radiation. We investigated incidence, treatment, and survival outcomes to observe any trends in response to improvements in surgical and radiation techniques over a near 40-year time period.


METHODS
Three hundred forty-five microscopically confirmed cases of sacral chordoma were identified between 1974 and 2011 from the surveillance, epidemiology, and end results program of the National Cancer Institute. Cases were divided into three cohorts by calendar year, 1974-1989, 1990-1999, and 2000-2011, as well as into two groups by age ≤65 versus >65 to investigate trends over time and age via Chi-square analysis. Kaplan-Meier analyses were performed to determine effects of treatment on survival. Multivariate Cox regression analysis was performed to determine predictors of overall survival (OS).


RESULTS
Five-year OS for the entire cohort was 60.0%. OS correlated significantly with treatment modality, with 44% surviving at 5 years with no treatment, 52% with radiation alone, 82% surgery alone, and 78% surgery and radiation (p < 0.001). Age >65 was significantly associated with non-surgical management with radiation alone or no treatment (p < 0.001). Relatively, fewer patients received radiation between 2000 and 2011 compared to prior time periods (p = 0.03) versus surgery, for which rates which did not vary significantly over time (p = 0.55). However, 5-year OS was not significantly different by time period. Age group and treatment modality were predictive for OS on multivariate analysis (p < 0.001).


CONCLUSIONS
Surgery remains an important component in the treatment of sacral chordomas in current practice. Fewer patients were treated with radiation more recently despite advances in photon and proton beam radiation. OS remains unchanged. Additional analyses of margin status, radiation modality, and local control in current practice are warranted.
Radiation Oncology, Tufts Medical Center , Boston, MA , USA.
Esther
E
Yu
Radiation Oncology, Tufts Medical Center , Boston, MA , USA.
Paul P
PP
Koffer
Radiation Oncology, Tufts Medical Center, Boston, MA, USA; Radiation Oncology, Warren Alpert Medical School of Brown University, Providence, RI, USA.
Thomas A
TA
DiPetrillo
Radiation Oncology, Warren Alpert Medical School of Brown University , Providence, RI , USA.
Timothy J
TJ
Kinsella
IMRT; SBRT; chordoma; heavy ion; protons
J Surg Oncol. 2014 Aug;110(2):115-22
24752878
J Bone Joint Surg Am. 2005 Oct;87(10):2211-6
16203885
Int J Radiat Oncol Biol Phys. 2010 Aug 1;77(5):1470-6
19939576
Int J Radiat Oncol Biol Phys. 2004 Feb 1;58(2):631-40
14751537
Neurosurgery. 2013 Oct;73(4):673-80; discussion 680
23842548
Int J Radiat Oncol Biol Phys. 2006 Aug 1;65(5):1514-21
16757128
Cancer. 2000 May 1;88(9):2122-34
10813725
Int J Radiat Oncol Biol Phys. 2010 Feb 1;76(2):326-32
20117285
Neurosurgery. 1999 Jan;44(1):74-9; discussion 79-80
9894966
Neurosurgery. 2009 Feb;64(2 Suppl):A44-53
19165073
Radiother Oncol. 1996 Oct;41(1):67-72
8961370
Clin Orthop Relat Res. 2008 Sep;466(9):2217-23
18584264
Int J Radiat Oncol Biol Phys. 2000 Jun 1;47(3):591-6
10837940
Neurosurg Clin N Am. 2008 Jan;19(1):5-15
18156043
Radiother Oncol. 1993 Oct;29(1):27-32
8295984
Spine (Phila Pa 1976). 2015 Apr 15;40(8):544-9
25627289
Br J Radiol. 2014 Jan;87(1033):20130512
24288399
Spine (Phila Pa 1976). 2009 Sep 15;34(20):2233-9
19752710
Int J Radiat Oncol Biol Phys. 2016 May 1;95(1):322-7
27084649
Radiother Oncol. 2010 Dec;97(3):408-12
21056488
Int J Radiat Oncol Biol Phys. 2011 Jan 1;79(1):110-6
20400242
Int J Radiat Oncol Biol Phys. 2012 Jun 1;83(2):542-51
22137019