Incidence and survival rates and trends of skull Base chondrosarcoma: A Population-Based study

Medicare Reimbursement and Utilization Trends Within Skull Base Surgery

BACKGROUND

Medicare reimbursements for otolaryngology and neurosurgery procedures have generally declined since 2000. We explore Medicare reimbursement trends for anterior cranial fossa, middle cranial fossa, posterior cranial fossa, pituitary surgery, and skull base reconstruction surgery from 2000-2022.

METHODS

Cross-sectional analysis of the Centers for Medicare and Medicaid Services Physician Fee Schedule was performed from 2000-2022 on approach, resection, and repair of the skull base (Current Procedural Terminology codes 31290-31291, 61546, 61548, 61575-61619, and 62165). Reimbursement data were adjusted for inflation to 2022 U.S. dollars, and annual and total changes calculated. The Centers for Medicare and Medicaid Services Part B National Summary Data File was analyzed for trends in Medicare procedure volume and total payment.

RESULTS

Adjusted for inflation since 2000, reimbursements for anterior cranial fossa, middle cranial fossa, posterior cranial fossa, pituitary surgery, and skull base reconstruction codes had an overall decrease of 22.85%, 32.43%, 28.09%, 44.22%, and 38.65%, respectively. Simultaneously, procedure volume increased at an average annual rate of 63.99%, 128.57%, 19.75%, 36.11%, and 12.79%, respectively.

CONCLUSIONS

While nominal per-service Medicare reimbursement has increased for skull base surgery codes, there has been a downward trend in inflation-adjusted procedural reimbursement. This parallels findings in other otolaryngology and neurosurgery procedures. Despite this, surgical volume in all skull base surgery subfields has increased, indicating increased utility and adoption of these techniques.

Proton-Based Radiation Therapy for Skull Base Chondrosarcomas in Children and Adolescents: 40-Year Experience From the Massachusetts General Hospital

PURPOSE

The literature on skull base chondrosarcoma (CHS) is scarce. We report outcomes for pediatric and young patients ≤22 years with base of skull CHSs treated with proton-based radiation therapy (PBRT).

METHODS AND MATERIALS

We retrospectively reviewed all patients treated with PBRT between 1981 and 2023. Primary endpoints were overall survival (OS), chondrosarcoma-specific survival (CSS), progression-free survival (PFS), local control, and distal control.

RESULTS

Eighty-four patients were identified. Median age at diagnosis was 19 years (range, 6-22). Most patients (n = 79, 94%) had conventional CHS, whereas 5 (6%) had mesenchymal CHS. Nine patients (11%) underwent gross total resection, 64 (76%) subtotal resection, and 11 patients (13%) underwent biopsy. Twenty-four (29%) patients progressed before radiation therapy. The median prescription dose was 70 Gy (relative biological equivalent) (range, 50-79.7). At a median follow-up of 18.0 years (IQR, 9.2-26.2) from diagnosis, 11 patients recurred (7 local, 4 distant). Six patients died of disease. Five patients died of other causes. Ten-year OS, CSS, and PFS rates for all patients were 93.3%, 94.7%, and 88%, respectively. Twenty-year OS, CSS, and PFS rates for conventional CHS (n = 79) were 93.1%, 97.1%, and 89.2%, respectively. Mesenchymal histology was significantly associated with worse OS and PFS. Preradiation therapy tumor progression portended worse OS and CSS. Eight patients (9.9 %) experienced a late toxicity grade 3 or greater.

CONCLUSIONS

This is the largest cohort of pediatric base of skull CHSs in literature to date. High-dose PBRT after surgical resection achieves excellent disease control with minimal toxicity.

A Prospective Phase I/II Clinical Trial of High-Dose Proton Therapy for Chordomas and Chondrosarcomas

Purpose

The purpose of this study was to evaluate the feasibility and safety of dose-escalated proton beam therapy for treating chordomas and chondrosarcomas of the skull base and spine. Methods: A prospective cohort of 54 patients (42 with chordomas and 12 with chondrosarcomas) was enrolled between 2010 and 2018. The primary endpoints were feasibility and <20% rate of acute grade ≥3 toxicity, and secondary endpoints included cancer-specific outcomes and toxicities. Patients were followed with magnetic resonance imaging or computed tomography at 3-month intervals. Proton beam therapy was delivered with doses up to 79.2 Gy using protons only, combination protons/intensity modulated radiation therapy (IMRT), or IMRT only.

Results

Feasibility endpoints were met, with only 2 out of 54 patient radiation therapy plans failing to meet dosimetric constraints with protons, and 4 out of 54 experiencing a delay or treatment break >5 days, none for toxicities related to treatment. There were no grade 4 acute toxicities and 1 grade 3 acute toxicity (sensory neuropathy). The only 2 grade 3 late toxicities recorded, osteoradionecrosis and intranasal carotid blowout (mild and not emergently treated), occurred in a single patient. We report overall survival as 83% at 5 years, with local failure-free survival and progression-free survival rates of 72% and 68%, respectively. Five patients developed distant disease, and among the 9/54 patients who died, 4 deaths were not attributed to treatment or recurrence.

Conclusions

Our findings suggest that high-dose proton therapy alone or in combination with IMRT is a safe and effective treatment option for chordomas and chondrosarcomas of the skull base and spine.

DWI-Detected Ischemic Lesions after Endovascular Treatment for Cerebral Aneurysms: An Updated Systematic Review and Meta-analysis

BACKGROUND AND PURPOSE

DWI-detected ischemic lesions are potential complications of endovascular procedures that are performed to treat intracranial aneurysms. We completed a systematic review and meta-analysis to identify the occurrence of DWI-detected ischemic lesions after endovascular treatment for intracranial aneurysms.

MATERIALS AND METHODS

A systematic literature search of PubMed, the Web of Science, EMBASE, and Scopus between January 2000 and June 2022 of post-endovascular procedures for intracranial aneurysm studies was conducted using the Nested Knowledge AutoLit software. The main outcome was DWI-detected ischemic lesions within 5 days of the procedures. Information regarding associated risk factors such as the type of procedure, patient demographics, and aneurysm characteristics was also collected.

RESULTS

Twenty-nine studies with 2686 patients were included. The overall incidence of DWI ischemic lesions was 47.0% (95% CI, 39.6%-55.8%). The highest rate of lesions was seen with flow diversion at 62.4% (95% CI, 48.4%-80.5%), followed by complex procedures at 49.3% (95% CI, 29.5%-82.1%), stent-assisted coiling at 47.5% (95% CI, 34.6%-65.3%), simple coiling at 47.1% (95% CI, 35.7%-62.3%), and balloon-assisted coiling at 37.0% (95% CI, 28.3%-48.4%). The differences among different techniques were not statistically significant; however, there was significant heterogeneity and a significant risk of publication bias among included studies.

CONCLUSIONS

Many patients who undergo endovascular procedures for intracranial aneurysms present with new postprocedural DWI-detected ischemic lesions, regardless of the endovascular procedure used. Future studies and meta-analyses are needed to investigate early and long-term outcomes of such small infarcts.

Are we improving? Temporal trends in outcomes for mechanical thrombectomy for stroke: A systematic review and meta-analysis of randomized trials

BACKGROUND

In 2015, mechanical thrombectomy (MT) was deemed the standard of care for acute ischemic stroke (AIS) in the anterior circulation due to large vessel occlusion (LVO). To determine if outcomes in patients treated with MT have changed, we conducted a systematic review and meta-analysis of published randomized controlled trials (RCTs).

METHODS

A systematic literature review of the English language literature was conducted using PubMed. We included RCTs that focused on patients with AIS treated with MT. The primary outcome of interest was good functional outcome defined as modified Rankin Scale (mRS) 0-2 at 90 days. Safety outcomes included rates of symptomatic intracranial hemorrhage (sICH) and mortality at 90 days. Using Joinpoint Regression Analysis Program, we calculated the average annual percent change (AAPC) for the outcomes of interest.

RESULTS

We included 23 RCTs with 5784 patients. The years of mid-enrollment among the included RCTs ranged from 2012-2020. There was an AAPC of +3.82% between 2012 and 2020 (95% CI 0.4 to 7.3; P-value = 0.033) in rates of good functional outcome. There was an AAPC of +6.98% between 2012 and 2020 (95% CI 0.5 to 13.9; P-value = 0.039) in rates of sICH. There was an AAPC of -0.49% between 2012 and 2020 (95% CI -4.4 to 3.5; P-value = 0.77) in rates of mortality.

CONCLUSION

Between 2012 and 2020, rates of good functional outcome and sICH increased, while rates of mortality remained consistent in RCTs investigating MT for AIS. Multiple factors likely influenced our results, including increased use of MT and utilization of adjunctive therapies alongside MT.

Skull Base Registries: A Roadmap

Hospitals, payors, and patients increasingly expect us to report our outcomes in more detail and to justify our treatment decisions and costs. Although there are many stakeholders in surgical outcomes, physicians must take the lead role in defining how outcomes are assessed. Skull base lesions interact with surrounding anatomy to produce a complex spectrum of presentations and surgical challenges, requiring a wide variety of surgical approaches. Moreover, many skull base lesions are relatively rare. These factors and others often preclude the use of prospective randomized clinical trials, thus necessitating alternate methods of scientific inquiry. In this paper, we propose a roadmap for implementing a skull base registry, along with expected benefits and challenges.

Revisitation of imaging features of skull base chondrosarcoma in comparison to chordoma

PURPOSE

Pre-surgical diagnosis of skull base chondrosarcoma (SBC) is often challenging due to the resemblance to chordoma. The goal of this study was to develop an optimal method for predicting SBC diagnosis.

METHODS

This retrospective study included patients with histologically diagnosed SBC and skull base chordoma. Their clinical and radiologic features were compared, and the predictive factors of SBC were examined.

RESULTS

Forty-one patients with SBC and 41 with chordoma were included. Most SBCs exhibited hypointensity (25, 64.1%) or isointensity (12, 30.8%) on T1-weighted images, and hyperintensity (34, 87.1%) or mixed intensity (5, 12.8%) on T2-weighted images. MRI contrast enhancement was usually avid or fair (89.7%) with "arabesque"-like pattern (41.0%). The lateral/paramidline location was more common in SBC than in chordoma (85.4% vs. 9.8%; P < 0.01), while midline SBCs (14.6%) were also possible. Multivariate analysis demonstrated that higher apparent diffusion coefficient (ADC) value (unit odds ratio 1.01; 95% confidence interval 1.00-1.02; P < 0.01) was associated with an SBC diagnosis. An ADC value of ≥ 1750 × 10^-6 mm²/s demonstrated a strong association with an SBC diagnosis (odds ratio 5.89 × 10²; 95% confidence interval 51.0-6.80 × 10³; P < 0.01) and yielded a sensitivity of 93.9%, specificity of 97.4%, positive predictive value of 96.9%, and negative predictive value of 95.0%.

CONCLUSION

The ADC-based method is helpful in distinguishing SBC from chordoma and readily applicable in clinical practice. The prediction accuracy increases when other characteristics of SBC, such as non-midline location and arabesque-like enhancement, are considered together.

Racial disparity in recommendation for surgical resection of skull base chondrosarcomas: A Surveillance, Epidemiology, and End Results (SEER) analysis

INTRODUCTION

There is increased appreciation of racial disparities in the delivery of neurosurgical care. Here, we explore whether race influences surgical recommendations in the management of skull base chondrosarcomas.

METHODS

We identified 493 patients with skull base chondrosarcoma using the Surveillance, Epidemiology, and End Results (SEER) registry (November 2017 submission). Regression analyses were performed to identify demographic variables associated with recommendation against surgery. Univariate and multivariate cox proportional hazards models were used for survival analysis.

RESULTS

In a univariate analysis, we found that the African-American race was associated with an increased likelihood of surgeon recommendation against surgery (OR = 4.416, 95% CI = 1.893-10.302, p = 0.001). This association remained robust in the multivariate model that controlled for other covariates, including age of diagnosis (OR = 5.091, 95% CI = 2.127-12.187, p < 0.001). For patients who received a recommendation against surgery, the likelihood of dying from non-chondrosarcoma causes was comparable between Caucasian and African-American patients, suggesting that the prevalence and severity of medical conditions that increase the risk of death were comparable between these cohorts (HR = 0.466, 95% CI = 0.057-3.802, p = 0.475). The likelihood of dying from chondrosarcoma was comparable between Caucasian and African-American patients who underwent surgery (HR = 0.982, 95% CI = 0.353-2.732, p = 0.973), suggesting absence of race-specific surgical benefits.

CONCLUSION

We identified a racial disparity against African-Americans in recommendations for surgical resection of skull base chondrosarcomas.

Determinants of survival in sinonasal and skull base chondrosarcoma: An analysis of the National Cancer Database

BACKGROUND

Chondrosarcomas are rare, malignant chondroid tumors that can occur in the sinonasal and skull base regions. Surgery is a mainstay of treatment, but complete resection can be challenging because of the close proximity of critical neurovascular structures. Because of their rarity and relatively indolent nature, optimal treatment regimens are not established. Our objective was to assess determinants of survival for sinonasal and skull base chondrosarcomas utilizing the National Cancer Database (NCDB).

METHODS

The NCDB (2004-2017) was queried for cases of sinonasal and skull base chondrosarcoma. Multivariate hazard regression modeling was used to identify significant predictors of 60-month and 120-month overall survival (OS).

RESULTS

Seven hundred thirty-six cases met inclusion criteria. OS for all treatment types was 84.7% [SE±0.02] at 60 months and 75.6% [SE±0.02] at 120 months. Surgery with or without adjuvant treatment was found to associate with highest OS at 60 and 120 months. For patients receiving adjuvant radiation during treatment, proton therapy had significantly better OS at 60 months (95.4% [SE±0.03] vs 82.3% [SE±0.03], -²  = 5.27; p = 0.02) and 120 months (85.1% [SE±0.08] vs 72.8% [SE±0.05], -²  = 4.11; p = 0.04) compared with conventional external beam. After adjustment for primary site, multivariate Cox regression modeling (n = 561) identified cofactors significantly associated with variation in mortality risk at 60 and 120 months, including age, Charlson-Deyo total score ≥ 3, insurance provision status, and tumor grade.

CONCLUSIONS

Sinonasal and skull base chondrosarcoma are primarily treated with surgery with favorable OS. Adjuvant treatment may be required and proton radiation was associated with improved 60-month and 120-month survival compared with conventional radiation.

Chondrosarcoma-from Molecular Pathology to Novel Therapies

Chondrosarcoma (CHS) is the second most common primary malignant bone sarcoma. Overall survival and prognosis of this tumor are various and often extreme, depending on histological grade and tumor subtype. CHS treatment is difficult, and surgery remains still the gold standard due to the resistance of this tumor to other therapeutic options. Considering the role of differentiation of CHS subtypes and the need to develop new treatment strategies, in this review, we introduced a multidisciplinary characterization of CHS from its pathology to therapies. We described the morphology of each subtype with the role of immunohistochemical markers in diagnostics of CHS. We also summarized the most frequently mutated genes and genome regions with altered pathways involved in the pathology of this tumor. Subsequently, we discussed imaging methods and the role of currently used therapies, including surgery and the limitations of chemo and radiotherapy. Finally, in this review, we presented novel targeted therapies, including those at ongoing clinical trials, which can be a potential future target in designing new therapeutics for patients with CHS.