Treatment of a large, symptomatic skull metastasis requires surgical excision and in many cases postoperative radiation therapy. Immediate reconstruction of the skull for cerebral protection usually involves cranioplasty with titanium mesh and/or methyl methacrylate. Preoperative synthetic cranioplasty technology is yet to evolve sufficiently to allow computer-generated prostheses to precisely fit a defined craniectomy defect created at the time of tumor removal. We document the techniques used for simultaneous craniectomy and composite cranioplasty in the setting of a large occipital renal cell skull metastasis. Preoperative computed tomography (CT) and magnetic resonance (MR) imaging identified the pathological anatomy of an occipital skull metastasis presenting as an exophytic scalp mass. Preoperative angiography and embolization was performed followed by craniectomy in the semi-sitting position and composite cranioplasty using titanium mesh and methyl methacrylate. A series of steps in the surgical procedure are outlined to assist with safely and accurately performing the craniectomy and cranioplasty to guarantee the best surgical and cosmetic outcome. Postoperative CT imaging confirmed excellent contours of the cranioplasty. The method described herein allows for a single-step surgical procedure to excise a large skull metastasis and create a structurally sound and cosmetically acceptable composite cranioplasty. This method can also be used for the excision and repair of other skull tumors or anomalies requiring excision.

Abstract

BACKGROUND

Metastasis of melanoma to the brain is associated with poor outcomes. Recent trials demonstrate improved survival after treatment with immune checkpoint inhibitors.

OBJECTIVE

To examine the impact that checkpoint inhibitor treatment has on overall survival (OS) and central nervous system (CNS) progression in a cohort of patients undergoing surgical resection of melanoma brain metastases.

METHODS

This retrospective, single-center study included patients undergoing first-time surgical resection of melanoma brain metastases. A multivariate Cox proportional model was used to estimate the association of patient and treatment factors with OS and CNS progression.

RESULTS

85 patients underwent first-time resection of 97 melanoma brain metastases with a median follow-up of 9.5 months. Checkpoint inhibitors (Pembrolizumab, Ipilimumab, and/or Nivolumab) were used in 55.1% of cases (19 pre-op; 47 post-op; median 9 cycles). Patients treated with checkpoint inhibitors had similar peri-op systemic disease status and KPS but had been treated with more systemic agents and had more instances of CNS progression prior to surgery. Median OS and time to CNS progression for the cohort were 1 year and 237 days, respectively. In a multivariate Cox regression model, age (HR 1.03 by decade; p=0.02), treatment with a checkpoint inhibitor (HR 0.27; p<0.0001), prior radiotherapy (HR 2.44; p=0.007), and number of brain metastases at the time of surgery (HR 1.05 per metastasis; p=0.04) were significant predictors of OS. Checkpoint inhibitor treatment was associated with longer OS from surgery (median 3 vs 0.5 yrs, log-rank p=0.004). However, patients who underwent craniotomy after prior checkpoint inhibitor treatment had poor OS (median 0.56 yrs). Prior radiotherapy was also associated with poor OS (median 0.53 yrs).

CONCLUSIONS

While checkpoint inhibitor treatment was associated with improved survival in this surgical cohort of melanoma brain metastases, patients who require surgical resection after checkpoint inhibitor treatment or radiotherapy are poor surgical candidates.

Abstract

Background

Despite the promising results for treating metastatic cancer with checkpoint inhibitor immunotherapies, there are limited data on surgical outcomes for brain metastases (BMs) that have progressed after prior checkpoint inhibitor treatment. The objective of this study was to identify factors associated with local progression, leptomeningeal disease, and survival for patients undergoing surgical resection of a BM in patients previously treated with checkpoint inhibitor immunotherapy.

Methods

A retrospective, single-center cohort study was conducted with inclusion of adult patients undergoing surgical resection of a BM in the setting of progression after prior checkpoint inhibitor treatment. Univariate and multivariate analyses were performed to identify factors associated with outcomes of interest.

Results

Over an 8-year period, 26 patients who underwent resection of 30 BMs met inclusion criteria. Median patient age at surgery was 63.9 years, and median clinical follow-up was 6.9 months (range 0.1 – 52.9). Extracranial disease was present at the time of surgery in 73.3% of cases. There were 6 postoperative complication events (20% of cases) by 30-days. By last follow-up, 65.4% of the cohort had died with a median censored survival of 7.6 months from surgery. Eight patients (30.8%) died within 3 months of surgery. On multivariate analysis, postoperative complications were associated with worse survival (HR 5.33, 95%CI 1.15–24.77, p=0.03). Four BMs had local progression (13.3%), and 60% of procedures were associated with distant progression within a median time of 3.6 months. Leptomeningeal disease developed in 32% of cases. On multivariate analysis, increased time from BM diagnosis to surgery was associated with a greater risk of leptomeningeal disease (OR 1.2, 95%CI 1.00–1.43, p=0.021).

Conclusion

Patients who require BM resection after prior checkpoint inhibitor treatment have an overall poor prognosis. Although local control rates are acceptable, these patients are at high risk for developing leptomeningeal disease postoperatively.

Here we evaluated the utility of MRI to monitor intrathecal infusions in nonhuman primates. Adeno-associated virus (AAV) spiked with gadoteridol, a gadolinium-based MRI contrast agent, enabled real-time visualization of infusions delivered either via cerebromedullary cistern, lumbar, cerebromedullary and lumbar, or intracerebroventricular infusion. The kinetics of vector clearance from the cerebrospinal fluid (CSF) were analyzed. Our results highlight the value of MRI in optimizing the delivery of infusate into CSF. In particular, MRI revealed differential patterns of infusate distribution depending on the route of delivery. Gadoteridol coverage analysis showed that cerebellomedullary cistern delivery was a reliable and effective route of injection, achieving broad infusate distribution in the brain and spinal cord, and was even greater when combined with lumbar injection. In contrast, intracerebroventricular injection resulted in strong cortical coverage but little spinal distribution. Lumbar injection alone led to the distribution of MRI contrast agent mainly in the spinal cord with little cortical coverage, but this delivery route was unreliable. Similarly, vector clearance analysis showed differences between different routes of delivery. Overall, our data support the value of monitoring CSF injections to dissect different patterns of gadoteridol distribution based on the route of intrathecal administration.

Background

There is a concern that glioma patients undergoing repeat craniotomies are more prone to complications. The study's goal was to assess if the complication profiles for initial and repeat craniotomies were similar, to determine predictors of complications, and to compare results with those in the literature.

Methods

A retrospective study was conducted of glioma patients (WHO grade II-IV) who underwent either an initial or repeat craniotomy performed by the senior author from 2012 until 2019. Complications were recorded by discharge, 30 days, and 90 days postoperatively. New neurologic deficits were recorded by 90 days postoperatively. Multivariate regression was performed to identify factors associated with complications. A meta-analysis was performed to identify rates of complications based on number of prior craniotomies.

Results

Within the cohort of 714 patients, 400 (56%) had no prior craniotomies, 218 (30.5%) had undergone 1 prior craniotomy, and 96 (13.5%) had undergone ≥ 2 prior craniotomies. There were 27 surgical and 10 medical complications in 30 patients (4.2%) and 19 reoperations for complications in 19 patients (2.7%) with no deaths by 90 days. Complications, reoperation rates, and new neurologic deficits did not differ based on number of prior craniotomies. On multivariate analysis, older age (OR1.5, 95%CI 1.0-2.2) and significant leukocytosis due to steroid use (OR12.6, 95%CI 2.5-62.9) were predictors of complications. Complication rates in the cohort were lower than rates reported in the literature.

Conclusion

Contrary to prior reports in the literature, repeat craniotomies can be as safe as initial operations if surgeons implement best practices.

Niemann-Pick disease type A (NPD-A) is a lysosomal storage disorder characterized by neurodegeneration and early death. It is caused by loss-of-function mutations in the gene encoding for acid sphingomyelinase (ASM), which hydrolyzes sphingomyelin into ceramide. Here, we evaluated the safety of cerebellomedullary (CM) cistern injection of adeno-associated viral vector serotype 9 encoding human ASM (AAV9-hASM) in nonhuman primates (NHP). We also evaluated its therapeutic benefit in a mouse model of the disease (ASM-KO mice). We found that CM injection in NHP resulted in widespread transgene expression within brain and spinal cord cells without signs of toxicity. CM injection in the ASM-KO mouse model resulted in hASM expression in cerebrospinal fluid and in different brain areas without triggering an inflammatory response. In contrast, direct cerebellar injection of AAV9-hASM triggered immune response. We also identified a minimally effective therapeutic dose for CM injection of AAV9-hASM in mice. Two months after administration, the treatment prevented motor and memory impairment, sphingomyelin (SM) accumulation, lysosomal enlargement, and neuronal death in ASM-KO mice. ASM activity was also detected in plasma from AAV9-hASM CM-injected ASM-KO mice, along with reduced SM amount and decreased inflammation in the liver. Our results support CM injection for future AAV9-based clinical trials in NPD-A as well as other lysosomal storage brain disorders.