Extent of Surgical Resection as a Predictor of Tumor Progression in Skull Base Chordomas: A Multicenter Volumetric Analysis.

INTRODUCTION: Skull-base chordomas are aggressive tumors with a propensity for recurrence/progression. Even with standard of care (SoC), 5-year recurrence rates are variable (19%-54%). This high recurrence/progression rate correlates with increased morbidity and mortality. We sought to analyze a multicenter cohort of skull base chordomas to identify predictors of progression in patients receiving SoC. METHODS: The [Blinded]-Neurosurgery data registry was queried for skull base chordomas treated from 2008-2020. Patients with the histopathologic diagnosis of chordoma were included. The cohort was composed of patients with preoperative and postoperative magnetic resonance imaging. Tumor volume and radiologic characteristics were obtained from axial T2 sequences using a Digital Imaging and Communications in Medicine viewer. Survival analysis was performed using Kaplan-Meier method, and time-to-event multivariate regression was performed to identify independent predictors of progression. RESULTS: The cohort included 195 patients, of which 66 patients met inclusion criteria; median age was 44, and 28 (42%) were females. Fifty-four (82%) received SoC, 7 (11%) resection only, and 5 (8%) radiotherapy only. Median preoperative and postoperative tumor volumes were 11.55 cm3 (0.33-54.89) and 0.34 cm3 (0-42.52), respectively. Recurrence rate with SoC was 37%. Postoperative tumor volume (P = 0.010) correlated with progression. A postoperative volume of >4.9 cm3 (P = 0.044), ≤81.3% of tumor resection (P = 0.02), and lower-clivus location (P < 0.005) correlated with decreased time to progression. CONCLUSIONS: Skull base chordomas can be challenging to resect. Even though maximal resection and radiotherapy improve rate of tumor progression, many of these lesions eventually recur. We have identified a postoperative tumor volume of ≥4.9 cm3 and extent of resection of ≤81.3% in this cohort as predictors of progression in patients receiving SoC.

Impact of facility type and volume on post-surgical outcomes following diagnosis of WHO grade II glioma.

OBJECTIVE: Low grade gliomas present unique and challenging scenarios. We aimed to identify if facility type and/or facility volume impact overall survival (OS) following diagnosis of WHO grade II gliomas. We also sought to compare early post-surgical outcomes based on these factors. METHODS: The National Cancer Database was queried for patients with WHO grade II gliomas diagnosed from 2004 to 2013 with known survival. Patients were grouped based on facility type and facility volume. Multivariable analyses were performed to investigate factors associated with OS following diagnosis, and Chi-square tests were used to compare early post-surgical outcomes. RESULTS: 6428 patients met inclusion criteria. Factors associated with improved OS on multivariable analysis included younger patient age, female gender, race, non-use of radiotherapy (each p < 0.001). Also, on multivariable analysis, OS was improved among patients treated at Academic/Research programs compared to those treated at Non-Academic/Research programs (HR 0.898, p = 0.014), but facility volume did not impact OS (p = 0.760). Thirty-day mortality did not differ by facility type (p = 0.265), but 90-day morality as well as 30-day readmission rates were more favorable in Academic/Research programs (p = 0.008 and <0.001, respectively). CONCLUSIONS: This study suggests that patients treated in Academic/Research programs have increased survival and generally more favorable early-postsurgical outcomes. The extent to which differences in patient populations, socioeconomic factors, and/or provider expertise play into this cause will be areas of future research.