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Tumor-to-tumor metastasis: esophageal carcinoma metastatic to an intracranial paraganglioma

Case report

Jian-Qiang Lu, Moosa Khalil, William Hu, Garnette R. Sutherland, and Arthur W. Clark

Tumor-to-tumor metastasis (TTM) is a relatively rare but well-documented phenomenon. The authors report a unique case of esophageal carcinoma metastatic to an intracranial paraganglioma. A sellar and suprasellar tumor was found using MR imaging in an 81-year-old man who presented with a 3-week history of progressive headache and blurred vision. A subtotal excision of the tumor was achieved. Histopathological examination of the tumor disclosed a neoplasm with two distinct components: one showing the classic Zellballen pattern of a paraganglioma, the other exhibiting malignant features leading to the diagnosis of a poorly differentiated carcinoma metastatic to a sellar/suprasellar paraganglioma. The primary esophageal carcinoma was not uncovered until 2 months later, after the patient presented with upper gastrointestinal bleeding. The patient died 4 months after initial presentation. This case expands the spectrum of TTM, and emphasizes the importance of TTM in the practice of pathology.

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A novel surgical planning system using an AI model to optimize planning of pedicle screw trajectories with highest bone mineral density and strongest pull-out force

Chi Ma, Da Zou, Huan Qi, Chentian Li, Cheng Zhang, Kedi Yang, Feng Zhu, Weishi Li, and William W. Lu

OBJECTIVE

The purpose of this study was to evaluate the ability of a novel artificial intelligence (AI) model in identifying optimized transpedicular screw trajectories with higher bone mineral density (BMD) as well as higher pull-out force (POF) in osteoporotic patients.

METHODS

An innovative pedicle screw trajectory planning system called Bone’s Trajectory was developed using a 3D graphic search and an AI-based finite element analysis model. The preoperative CT scans of 21 elderly osteoporotic patients were analyzed retrospectively. The AI model automatically calculated the number of alternative transpedicular trajectories, the trajectory BMD, and the estimated POF of L3–5. The highest BMD and highest POF of optimized trajectories were recorded and compared with AO standard trajectories.

RESULTS

The average patient age and average BMD of the vertebral bodies were 69.6 ± 7.8 years and 55.9 ± 17.1 mg/ml, respectively. On both sides of L3–5, the optimized trajectories showed significantly higher BMD and POF than the AO standard trajectories (p < 0.05). On average, the POF of optimized trajectory screws showed at least a 2.0-fold increase compared with AO trajectory screws.

CONCLUSIONS

The novel AI model performs well in enabling the selection of optimized transpedicular trajectories with higher BMD and POF than the AO standard trajectories.

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Thirty-day readmission and reoperation after surgery for spinal tumors: a National Surgical Quality Improvement Program analysis

Aditya V. Karhade, Viren S. Vasudeva, Hormuzdiyar H. Dasenbrock, Yi Lu, William B. Gormley, Michael W. Groff, John H. Chi, and Timothy R. Smith

OBJECTIVE

The goal of this study was to use a large national registry to evaluate the 30-day cumulative incidence and predictors of adverse events, readmissions, and reoperations after surgery for primary and secondary spinal tumors.

METHODS

Data from adult patients who underwent surgery for spinal tumors (2011–2014) were extracted from the prospective National Surgical Quality Improvement Program (NSQIP) registry. Multivariable logistic regression was used to evaluate predictors of reoperation, readmission, and major complications (death, neurological, cardiopulmonary, venous thromboembolism [VTE], surgical site infection [SSI], and sepsis). Variables screened included patient age, sex, tumor location, American Society of Anesthesiologists (ASA) physical classification, preoperative functional status, comorbidities, preoperative laboratory values, case urgency, and operative time. Additional variables that were evaluated when analyzing readmission included complications during the surgical hospitalization, hospital length of stay (LOS), and discharge disposition.

RESULTS

Among the 2207 patients evaluated, 51.4% had extradural tumors, 36.4% had intradural extramedullary tumors, and 12.3% had intramedullary tumors. By spinal level, 20.7% were cervical lesions, 47.4% were thoracic lesions, 29.1% were lumbar lesions, and 2.8% were sacral lesions. Readmission occurred in 10.2% of patients at a median of 18 days (interquartile range [IQR] 12–23 days); the most common reasons for readmission were SSIs (23.7%), systemic infections (17.8%), VTE (12.7%), and CNS complications (11.9%). Predictors of readmission were comorbidities (dyspnea, hypertension, and anemia), disseminated cancer, preoperative steroid use, and an extended hospitalization. Reoperation occurred in 5.3% of patients at a median of 13 days (IQR 8–20 days) postoperatively and was associated with preoperative steroid use and ASA Class 4–5 designation. Major complications occurred in 14.4% of patients: the most common complications and their median time to occurrence were VTE (4.5%) at 9 days (IQR 4–19 days) postoperatively, SSIs (3.6%) at 18 days (IQR 14–25 days), and sepsis (2.9%) at 13 days (IQR 7–21 days). Predictors of major complications included dependent functional status, emergency case status, male sex, comorbidities (dyspnea, bleeding disorders, preoperative systemic inflammatory response syndrome, preoperative leukocytosis), and ASA Class 3–5 designation (p < 0.05). The median hospital LOS was 5 days (IQR 3–9 days), the 30-day mortality rate was 3.3%, and the median time to death was 20 days (IQR 12.5–26 days).

CONCLUSIONS

In this NSQIP analysis, 10.2% of patients undergoing surgery for spinal tumors were readmitted within 30 days, 5.3% underwent a reoperation, and 14.4% experienced a major complication. The most common complications were SSIs, systemic infections, and VTE, which often occurred late (after discharge from the surgical hospitalization). Patients were primarily readmitted for new complications that developed following discharge rather than exacerbation of complications from the surgical hospital stay. The strongest predictors of adverse events were comorbidities, preoperative steroid use, and higher ASA classification. These models can be used by surgeons to risk-stratify patients preoperatively and identify those who may benefit from increased surveillance following hospital discharge.

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Histopathological validation of a three-dimensional magnetic resonance spectroscopy index as a predictor of tumor presence

Tracy R. McKnight, Mary H. von dem Bussche, Daniel B. Vigneron, Ying Lu, Mitchel S. Berger, Michael W. McDermott, William P. Dillon, Edward E. Graves, Andrea Pirzkall, and Sarah J. Nelson

Object. Data obtained preoperatively from three-dimensional (3D)/proton magnetic resonance (MR) spectroscopy were compared with the results of histopathological assays of tissue biopsies obtained during surgery to verify the sensitivity and specificity of a choline-containing compound—N-acetylaspartate index (CNI) used to distinguish tumor from nontumorous tissue within T2 hyperintense and contrast-enhancing lesions of patients with untreated gliomas. The information gleaned from the biopsy correlation study was used to test the hypothesis that there is metabolically active tumor in nonenhancing regions of the T2-hyperintense lesion that can be detected using MR spectroscopy.

Methods. Patients suspected of harboring a glioma underwent 3D MR spectroscopy during their preoperative MR imaging examination. Surgical navigation techniques were used to record the location of tissue biopsies collected during open resection of the tumor. A receiver operating curve analysis of the CNI and histological characteristics of specimens at each biopsy location was performed to determine the optimal threshold of the CNI required to separate tumor from nontumorous tissue. Histograms of the CNIs within enhancing and nonenhancing regions of lesions appearing on MR images were generated to determine the spatial distribution of CNIs consistent with tumor.

Conclusions. Biopsy samples containing tumor were distinguished from those containing a mixture of normal, edematous, gliotic, and necrotic tissue with 90% sensitivity and 86% specificity by using a CNI threshold of 2.5. The CNIs of nontumorous specimens were significantly different from those of biopsy specimens containing Grade II (p < 0.03), Grade III (p < 0.005), and Grade IV (p < 0.01) tumors. On average, one third to one half of the T2-hyperintense lesion outside the contrast-enhancing lesion contained CNI greater than 2.5.

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Letter to the Editor. Questionable value of 7-T MRI in Cushing's disease and relationship to inferior petrosal sinus sampling

Zihao Wang, Lu Gao, and Bing Xing

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Abstracts of the 2014 Annual Meeting of the Lumbar Spine Research Society Chicago, Illinois • May 1–2, 2014

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Abstracts of the 2013 Annual Meeting of the Lumbar Spine Research Society, Chicago, Illinois • April 11–12, 2013

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Oral Presentations

2010 AANS Annual Meeting Philadelphia, Pennsylvania May 1–5, 2010

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Oral Presentations 2014 AANS Annual Scientific Meeting San Francisco, California • April 5–9, 2014

Published online June 1, 2015; DOI: 10.3171/2015.6.JNS.AANS2014abstracts

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Abstracts of the 2017 AANS/CNS Joint Section on Disorders of the Spine and Peripheral Nerves Las Vegas, Nevada • March 8–11, 2017