Chordomas are rare, malignant bone tumors of the skull-base and axial skeleton. Until recently, there was no consensus among experts regarding appropriate clinical management of chordoma, resulting in inconsistent care and suboptimal outcomes for many patients. To address this shortcoming, the European Society of Medical Oncology (ESMO) and the Chordoma Foundation, the global chordoma patient advocacy group, convened a multi-disciplinary group of chordoma specialists to define by consensus evidence-based best practices for the optimal approach to chordoma. In January 2015, the first recommendations of this group were published, covering the management of primary and metastatic chordomas. Additional evidence and further discussion were needed to develop recommendations about the management of local-regional failures. Thus, ESMO and CF convened a second consensus group meeting in November 2015 to address the treatment of locally relapsed chordoma. This meeting involved over 60 specialists from Europe, the United States and Japan with expertise in treatment of patients with chordoma. The consensus achieved during that meeting is the subject of the present publication and complements the recommendations of the first position paper.

Study Design. Retrospective cohort analysis of a nationwide administrative database.Objective. The aim of this study was to analyze the association between cannabis abuse and serious adverse events following elective spine surgery. Summary of Background Data. Cannabis is the most popular illicit drug in the United States, and its use has been increasing in light of state efforts to decriminalize and legalize its use for both medical and recreational purposes. Its legal status has long precluded extensive research into its adverse effects, and to date, little research has been done on the sequelae of cannabis on surgical patients, particularly in spine surgery. Methods. The 2012-2015 Nationwide Inpatient Sample was queried for all patients undergoing common elective spine surgery procedures. These patients were then grouped by the presence of concurrent diagnosis of cannabis use disorder and compared with respect to various peri-and postoperative complications, all-cause mortality, discharge disposition, length of stay, and hospitalization costs. Propensity score matching was utilized to control for potential baseline confounders.Results. A total of 423,978 patients met inclusion/exclusion criteria, 2393 (0.56%) of whom had cannabis use disorder. After controlling for baseline characteristics and comorbid tobacco use, these patients similar inpatient mortality, but higher rates of perioperative thromboembolism (odds ratio [OR] 2.2; 95% confidence interval [CI] 1.2-4.0; P ¼ 0.005), respiratory complications (OR 2.0; 95% CI 1.4 -2.9; P < 0.001), neurologic complications such as stroke and anoxic brain injury (OR 2.9; 95% CI 1.2-7.5; P ¼ 0.007), septicemia/sepsis (OR 1.5; 95% CI 1.0 to 2.5; P ¼ 0.031), and nonroutine discharge (P < 0.001), as well as increased lengths of stay (7.1 vs. 5.2 days, P < 0.001) and hospitalization charges ($137,631.30 vs. $116,112.60, P < 0.001). Conclusion. Cannabis abuse appears to be associated with increased perioperative morbidity among spine surgery patients. Physicians should ensure that a thorough preoperative drug use history is taken, and that affected patients be adequately informed of associated risks.

BACKGROUND Autologous bone removed during craniectomy is often the material of choice in cranioplasty procedures. However, when the patient's own bone is not appropriate (infection and resorption), an alloplastic graft must be utilized. Common options include titanium mesh and polyetheretherketone (PEEK)-based custom flaps. Often, neurosurgeons must decide whether to use a titanium or custom implant, with limited direction from the literature. OBJECTIVE To compare surgical outcomes of synthetic cranioplasties performed with titanium or vs custom implants. METHODS Ten-year retrospective comparison of patients undergoing synthetic cranioplasty with titanium or custom implants. RESULTS A total of 82 patients were identified for review, 61 (74.4%) receiving titanium cranioplasty and 21 (25.6%) receiving custom implants. Baseline demographics and comorbidities of the 2 groups did not differ significantly, although multiple surgical characteristics did (size of defect, indication for craniotomy) and were controlled for via a 2:1 mesh-to-custom propensity matching scheme in which 36 titanium cranioplasty patients were compared to 18 custom implant patients. The cranioplasty infection rate of the custom group (27.8%) was significantly greater (P = .005) than that of the titanium group (0.0%). None of the other differences in measured complications reached significance. Discomfort, a common cause of reoperation in the titanium group, did not result in reoperation in any of the patients receiving custom implants. CONCLUSION Infection rates are higher among patients receiving custom implants compared to those receiving titanium meshes. The latter should be informed of potential postsurgical discomfort, which can be managed nonsurgically and is not associated with return to the operating room.

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Optimization problems, particularly NP-Hard Combinatorial Optimization problems, are some of the hardest computing problems with no known polynomial time algorithm existing. Recently there has been interest in using dedicated hardware to accelerate the solution to these problems, with physical annealers and quantum adiabatic computers being some of the state of the art. In this work we demonstrate usage of the Restricted Boltzmann Machine (RBM) as a stochastic neural network capable of solving these problems efficiently. We show that by mapping the RBM onto a reconfigurable Field Programmable Gate Array (FPGA), we can effectively hardware accelerate the RBM's stochastic sampling algorithm. We benchmark the RBM against the DWave 2000Q Quantum Adiabatic Computer and the Optical Coherent Ising Machine on two such optimization problems: the MAX-CUT problem and finding the ground state of a Sherrington-Kirkpatrick (SK) spin glass. On these problems, the hardware accelerated RBM shows best in class performance compared to these other accelerators, with an empirical scaling performance of O(e −N ) for probability of reaching the ground state compared to a similar empirical O(e −N ) for the CIM (with the RBM showing a constant factor of improvement over the CIM) and empirical O(e −N 2) for the DWave Annealer. The results show up to 10 7 x and 10 5 x time to solution improvement compared to the DWave 2000Q on the MAX-CUT and SK problems respectively, along with a 150x and 1000x performance increase compared to the Coherent Ising Machine annealer on those problems. By using commodity hardware running at room temperature for acceleration, the RBM also has greater potential for immediate and scalable use.