Missing Genomic Resources for the Next Generation of Environmental Risk Assessment.

Environmental risk assessment traditionally relies on a wide range of in vivo testing to assess the potential hazards of chemicals in the environment. These tests are often time-consuming and costly and can cause test organisms' suffering. Recent developments of reliable low-cost alternatives, both in vivo- and in silico-based, opened the door to reconsider current toxicity assessment. However, many of these new approach methodologies (NAMs) rely on high-quality annotated genomes for surrogate species of regulatory risk assessment. Currently, a lack of genomic information slows the process of NAM development. Here, we present a phylogenetically resolved overview of missing genomic resources for surrogate species within a regulatory ecotoxicological risk assessment. We call for an organized and systematic effort within the (regulatory) ecotoxicological community to provide these missing genomic resources. Further, we discuss the potential of a standardized genomic surrogate species landscape to enable a robust and nonanimal-reliant ecotoxicological risk assessment in the systems ecotoxicology era.

Piperacillin-Tazobactam Compared With Cefoxitin as Antimicrobial Prophylaxis for Pancreatoduodenectomy: A Randomized Clinical Trial.

Importance: Despite improvements in perioperative mortality, the incidence of postoperative surgical site infection (SSI) remains high after pancreatoduodenectomy. The effect of broad-spectrum antimicrobial surgical prophylaxis in reducing SSI is poorly understood. Objective: To define the effect of broad-spectrum perioperative antimicrobial prophylaxis on postoperative SSI incidence compared with standard care antibiotics. Design, Setting, and Participants: Pragmatic, open-label, multicenter, randomized phase 3 clinical trial at 26 hospitals across the US and Canada. Participants were enrolled between November 2017 and August 2021, with follow-up through December 2021. Adults undergoing open pancreatoduodenectomy for any indication were eligible. Individuals were excluded if they had allergies to study medications, active infections, chronic steroid use, significant kidney dysfunction, or were pregnant or breastfeeding. Participants were block randomized in a 1:1 ratio and stratified by the presence of a preoperative biliary stent. Participants, investigators, and statisticians analyzing trial data were unblinded to treatment assignment. Intervention: The intervention group received piperacillin-tazobactam (3.375 or 4 g intravenously) as perioperative antimicrobial prophylaxis, while the control group received cefoxitin (2 g intravenously; standard care). Main Outcomes and Measures: The primary outcome was development of postoperative SSI within 30 days. Secondary end points included 30-day mortality, development of clinically relevant postoperative pancreatic fistula, and sepsis. All data were collected as part of the American College of Surgeons National Surgical Quality Improvement Program. Results: The trial was terminated at an interim analysis on the basis of a predefined stopping rule. Of 778 participants (378 in the piperacillin-tazobactam group [median age, 66.8 y; 233 {61.6%} men] and 400 in the cefoxitin group [median age, 68.0 y; 223 {55.8%} men]), the percentage with SSI at 30 days was lower in the perioperative piperacillin-tazobactam vs cefoxitin group (19.8% vs 32.8%; absolute difference, -13.0% [95% CI, -19.1% to -6.9%]; P < .001). Participants treated with piperacillin-tazobactam, vs cefoxitin, had lower rates of postoperative sepsis (4.2% vs 7.5%; difference, -3.3% [95% CI, -6.6% to 0.0%]; P = .02) and clinically relevant postoperative pancreatic fistula (12.7% vs 19.0%; difference, -6.3% [95% CI, -11.4% to -1.2%]; P = .03). Mortality rates at 30 days were 1.3% (5/378) among participants treated with piperacillin-tazobactam and 2.5% (10/400) among those receiving cefoxitin (difference, -1.2% [95% CI, -3.1% to 0.7%]; P = .32). Conclusions and Relevance: In participants undergoing open pancreatoduodenectomy, use of piperacillin-tazobactam as perioperative prophylaxis reduced postoperative SSI, pancreatic fistula, and multiple downstream sequelae of SSI. The findings support the use of piperacillin-tazobactam as standard care for open pancreatoduodenectomy. Trial Registration: ClinicalTrials.gov Identifier: NCT03269994.

Plant PhysioSpace: a robust tool to compare stress response across plant species.

Generalization of transcriptomics results can be achieved by comparison across experiments. This generalization is based on integration of interrelated transcriptomics studies into a compendium. Such a focus on the bigger picture enables both characterizations of the fate of an organism and distinction between generic and specific responses. Numerous methods for analyzing transcriptomics datasets exist. Yet, most of these methods focus on gene-wise dimension reduction to obtain marker genes and gene sets for, for example, pathway analysis. Relying only on isolated biological modules might result in missing important confounders and relevant contexts. We developed a method called Plant PhysioSpace, which enables researchers to compute experimental conditions across species and platforms without a priori reducing the reference information to specific gene sets. Plant PhysioSpace extracts physiologically relevant signatures from a reference dataset (i.e. a collection of public datasets) by integrating and transforming heterogeneous reference gene expression data into a set of physiology-specific patterns. New experimental data can be mapped to these patterns, resulting in similarity scores between the acquired data and the extracted compendium. Because of its robustness against platform bias and noise, Plant PhysioSpace can function as an inter-species or cross-platform similarity measure. We have demonstrated its success in translating stress responses between different species and platforms, including single-cell technologies. We have also implemented two R packages, one software and one data package, and a Shiny web application to facilitate access to our method and precomputed models.

Hospital-level Variation in Utilization of Surgery for Clinical Stage I-II Pancreatic Adenocarcinoma.

OBJECTIVE: To (1) evaluate rates of surgery for clinical stage I-II pancreatic ductal adenocarcinoma (PDAC), (2) identify predictors of not undergoing surgery, (3) quantify the degree to which patient- and hospital-level factors explain differences in hospital surgery rates, and (4) evaluate the association between adjusted hospital-specific surgery rates and overall survival (OS) of patients treated at different hospitals. BACKGROUND: Curative-intent surgery for potentially resectable PDAC is underutilized in the United States. METHODS: Retrospective cohort study of patients ≤85 years with clinical stage I-II PDAC in the 2004 to 2014 National Cancer Database. Mixed effects multivariable models were used to characterize hospital-level variation across quintiles of hospital surgery rates. Multivariable Cox proportional hazards models were used to estimate the effect of adjusted hospital surgery rates on OS. RESULTS: Of 58,553 patients without contraindications or refusal of surgery, 63.8% underwent surgery, and the rate decreased from 2299/3528 (65.2%) in 2004 to 4412/7092 (62.2%) in 2014 (P < 0.001). Adjusted hospital rates of surgery varied 6-fold (11.4%-70.9%). Patients treated at hospitals with higher rates of surgery had better unadjusted OS (median OS 10.2, 13.3, 14.2, 16.5, and 18.4 months in quintiles 1-5, respectively, P < 0.001, log-rank). Treatment at hospitals in lower surgery rate quintiles 1-3 was independently associated with mortality [Hazard ratio (HR) 1.10 (1.01, 1.21), HR 1.08 (1.02, 1.15), and HR 1.09 (1.04, 1.14) for quintiles 1-3, respectively, compared with quintile 5] after adjusting for patient factors, hospital type, and hospital volume. CONCLUSIONS: Quality improvement efforts are needed to help hospitals with low rates of surgery ensure that their patients have access to appropriate surgery.

Laparoscopic Common Bile Duct Exploration for Choledocholithiasis: Analysis of Practice Patterns of Intermountain HealthCare.

BACKGROUND: The ideal management of common bile duct (CBD) stones remains controversial, whether with single-stage management using laparoscopic CBD exploration (LCBDE) during laparoscopic cholecystectomy, or with 2-stage management using preoperative or postoperative ERCP. We wished to elucidate the practice patterns within our health system, which includes both large urban referral centers and small rural critical access hospitals. STUDY DESIGN: We conducted a retrospective data analysis from our 22-hospital, not-for-profit, integrated healthcare system. All patients with a diagnosis of choledocholithiasis who underwent laparoscopic cholecystectomy (LC) and either ERCP or LCBDE for duct clearance between 2008 and 2013 were included. Demographic data, along with disease-specific characteristics and outcomes, were collected and compared. RESULTS: During the study period, 37,301 patients underwent LC. Of these, 1,961 (5.3%) met inclusion criteria. Single-stage management with LC+LCBDE was performed in 28% of patients, and the remaining 72% underwent 2-stage management with ERCP (73% postoperative ERCP, 27% preoperative). Mean total number of procedures was lowest in the LC+LCBDE group vs the post-cholecystectomy ERCP group vs the preoperative ERCP group (mean 1.4 vs 2.1 vs 2.3; p < 0.05). Hospital charges were also lower in the LC+LCBDE group vs post-cholecystectomy ERCP vs preoperative ERCP groups ($9,000 vs $10,800 vs $14,200; p < 0.05). Single-stage vs two-stage management varied greatly between hospitals (from 0% to 93%). CONCLUSIONS: Single-stage management of CBD stones resulted in the fewest procedures and lower hospital charges without an increase in complications. Single-stage management (LC+LCBDE) of CBD stones is underused and can offer better value in today's cost-constrained environment.

Primary Caregiver Perception of Pain Control following Pediatric Adenotonsillectomy: A Cross-Sectional Survey.

OBJECTIVES: To (1) review pain medications prescribed following pediatric adenotonsillectomy (T&A), (2) identify pain medications reported to be helpful, and (3) compare parent-reported outcomes among various combinations of pain medications. STUDY DESIGN: Case series with planned data collection. SETTING: Multihospital network. SUBJECTS AND METHODS: The primary caregivers of children aged 1 to 18 years who underwent isolated T&A from June to December 2014 were contacted 14 to 21 days after surgery. Data collected included pain medications prescribed, medications most helpful in controlling pain, and duration that pain medication was required. Parents rated their children's pain on postoperative days 2, 3, 7, and 14 and reported the time to resumption of normal diet/activity, as well as any hospital return visits. RESULTS: The study cohort included 672 subjects of 1444 potential participants (46% response rate). The mean age of the patients was 7.9 ± 3.6 years. Narcotics were prescribed in 71.9%, and 70.4% were told to use ibuprofen. Children who took ibuprofen alone were significantly younger (P < .001). Pain was significantly less on postoperative days 2 and 3 in the ibuprofen-only group as compared with the groups taking narcotics only (P < .001) and ibuprofen with narcotics (P = .002). Those taking ibuprofen alone returned to normal activity (P < .001) and diet (P = .026) sooner than those taking ibuprofen with narcotics. No difference was seen in pain control on subgroup analysis comparing oxycodone and hydrocodone. CONCLUSIONS: For pediatric T&A, significant variation exists in the management of postoperative pain. Parents of children given ibuprofen reported less pain than those given narcotics with and without ibuprofen. Further studies are needed to identify the optimal pain regimen for children after T&A.

Unique features of a global human ectoparasite identified through sequencing of the bed bug genome.

The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host-symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome sequencing and annotation establish a solid foundation for future research on mechanisms of insecticide resistance, human-bed bug and symbiont-bed bug associations, and unique features of bed bug biology that contribute to the unprecedented success of C. lectularius as a human ectoparasite.

Variation in costs among surgeons and hospitals in Pediatric tympanostomy tube placement.

OBJECTIVES/HYPOTHESIS: 1) Identify the major expenses for outpatient pediatric tympanostomy tube placement in a multihospital network. 2) Compare differences for variations in costs among hospitals and surgeons. METHODS: An observational cohort study in a multihospital network using a standardized activity-based accounting system to determine hospital costs for tympanostomy tube placement from February 2011 to January 2015. Children aged 6 months to less than 3 years old who underwent same-day surgery (SDS) for tympanostomy tubes at 15 hospital facilities were included. Subjects with additional procedures were excluded. Hospital costs were subdivided into categories including operating room (OR), SDS preoperative, SDS postoperative, postanesthesia care unit, anesthesia, pharmacy, and OR supplies. RESULTS: The study cohort included 5,623 patients undergoing tympanostomy tube placement by 67 surgeons. Mean cost per surgery was $769 ± $3. Significant variations (P < 0.001) in mean cost per procedure were identified by hospital (range $1212 ± $38 to $509 ± $11) and by surgeon (range $1330 ± $75 to $660 ± $11). Operating room and SDS preoperative were the greatest expenditures; each category accounted for over 30% of overall costs. Pharmacy costs and OR costs were some of the major drivers of cost variation among surgeons. CONCLUSION: This study demonstrates that OR and SDS preoperative costs accounted for the greatest expenditure in tympanostomy tube placement, and significant variation exists among surgeons and hospitals within a multihospital network. Further research is needed to elucidate factors accounting for such variation in cost and the overall impact on patient outcomes. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:1935-1939, 2016.

Hospital and Surgeon Adherence to Pediatric Tonsillectomy Guidelines Regarding Perioperative Dexamethasone and Antibiotic Administration.

OBJECTIVES: To (1) determine adherence to American Academy of Otolaryngology-Head and Neck Surgery Foundation guidelines for pediatric tonsillectomy recommending routine administration of perioperative dexamethasone and against routine antibiotic administration among surgeons and hospitals in a multihospital network and (2) evaluate the impact of adherence on the risk of complications. STUDY DESIGN: Case series with chart review. SETTING: Multihospital network. SUBJECTS AND METHODS: A case series of 15,950 children aged 1 to 18 years undergoing same-day surgery adenotonsillectomy (T&A) within a multihospital network from 2008 to 2014 was reviewed to determine whether dexamethasone and/or antibiotics were given in the hospital. The frequency of dexamethasone and antibiotic administration was compared among surgeons and hospitals in the years before and after the guidelines were published. The frequency of complications was compared in adhering vs nonadhering surgeons. RESULTS: The study cohort included 15,950 children undergoing T&A at 19 hospitals by 74 surgeons. Of the patients before guideline publication, 98.4% (n = 7432) received dexamethasone compared with 98.9% of subjects after guideline publication (n = 8518). In total, 16.1% received antibiotics before the guidelines compared with 13.8% after. Prior to the guidelines, 27 of 74 surgeons (36%) routinely gave antibiotics. After the guidelines were published, 19 surgeons (26%) continued to give antibiotics more than 50% of the time. There was no difference in complication visits between adhering and nonadhering surgeons. CONCLUSIONS: Most hospitals and surgeons administered perioperative dexamethasone routinely. While the overall frequency of antibiotic administration decreased after the guidelines were published, a significant percentage of surgeons continued to give antibiotics routinely, suggesting the need for improved dissemination and implementation of guidelines to promote adherence.

RNA-Seq transcriptome analysis to identify genes involved in metabolism-based diclofop resistance in Lolium rigidum.

Weed control failures due to herbicide resistance are an increasing and worldwide problem that significantly affect crop yields. Metabolism-based herbicide resistance (referred to as metabolic resistance) in weeds is not well characterized at the genetic level. An RNA-Seq transcriptome analysis was used to find candidate genes that conferred metabolic resistance to the herbicide diclofop in a diclofop-resistant population (R) of the major global weed Lolium rigidum. A reference cDNA transcriptome (19 623 contigs) was assembled and assigned putative annotations. Global gene expression was measured using Illumina reads from untreated control, adjuvant-only control, and diclofop treatment of R and susceptible (S). Contigs that showed constitutive expression differences between untreated R and untreated S were selected for further validation analysis, including 11 contigs putatively annotated as cytochrome P450 (CytP450), glutathione transferase (GST), or glucosyltransferase (GT), and 17 additional contigs with annotations related to metabolism or signal transduction. In a forward genetics validation experiment, nine contigs had constitutive up-regulation in R individuals from a segregating F2 population, including three CytP450, one nitronate monooxygenase (NMO), three GST, and one GT. Principal component analysis using these nine contigs differentiated F2 -R from F2 -S individuals. In a physiological validation experiment in which 2,4-D pre-treatment induced diclofop protection in S individuals due to increased metabolism, seven of the nine genetically validated contigs were induced significantly. Four contigs (two CytP450, NMO, and GT) were consistently highly expressed in nine field-evolved metabolic resistant L. rigidum populations. These four contigs were strongly associated with the resistance phenotype and are major candidates for contributing to metabolic diclofop resistance.

Enhanced recovery after colon surgery in a community hospital system.

BACKGROUND: Enhanced recovery after colon surgery has not been widely adopted in the United States and Europe, despite evidence that postoperative complications and hospital length of stay are decreased. OBJECTIVE: We sought to evaluate the introduction of a comprehensive care process for enhanced recovery after colon surgery in 8 community hospitals. DESIGN: A system-wide, surgeon-directed, multidisciplinary committee developed a comprehensive enhanced-care quality-improvement program. Surgeons and operations leaders in each hospital developed the internal structure to implement the process. PATIENTS: Surgeons had the option of entering or not entering patients in the enhanced-care pathway. Other than trauma patients, there were no exclusion criteria. MAIN OUTCOME MEASURES: To limit selection bias, the study population included all patients undergoing colon resections (those entered and not entered in the care process). Length of stay, postoperative days, hospital costs, 30-day readmission rate, and return to surgery for the study population were compared with a 2-year historical baseline. RESULTS: Forty-two percent of the study population was entered in the enhanced-care process. The average length of stay and the number of postoperative days in the study population decreased by 1.5 (P < .0001) and 1.3 (P < .0001) days. The rate of readmissions and returns to surgery remained stable (P > .05), and the average hospital cost decreased by $1763 (P = .02). Generalized linear regression analysis demonstrated that the enhanced-care process was a more significant variable than was the surgical approach (laparoscopic vs open surgery) in decreasing length of stay. LIMITATIONS: The degree of compliance with care process elements and the relative contribution of each element of the care process are unknown. CONCLUSIONS: A comprehensive enhanced-care colon surgery care process was successfully introduced in a community hospital system, as indicated by the clinical outcome measures.

Role of sentinel lymph node biopsy in the staging of synovial, epithelioid, and clear cell sarcomas.

BACKGROUND: Soft tissue sarcomas generally have a

The outcome of surgical resection versus assignment to the liver transplant waiting list for hepatocellular carcinoma.

BACKGROUND: Optimal management of patients with hepatocellular carcinoma (HCC) is controversial. This study was conducted to evaluate the outcome of tumor resection versus assignment to a liver transplant waiting list (WL) in patients with HCC. METHODS: Prospectively collected patient data from 1970 to 1997 on 313 patients with HCC were retrospectively analyzed by multivariate analysis to determine the effect of liver disease, method of treatment, and tumor-related factors on survival. RESULTS: A total of 199 patients underwent nonsurgical palliative care (PC), 81 underwent partial liver resection (LR), and 33 were assigned to a liver transplant WL, of which 22 received a donor liver. A total of 91%, 53%, and 91% of the patients had cirrhotic livers in the PC, LR, and WL groups, respectively (P < .001). In the LR group, the absence of a tumor capsule (P < .0001) and a poorly differentiated tumor (P = .027) were both adverse prognostic factors. In the WL group, hepatitis B (P = .02) and American Joint Committee on Cancer tumor stage III (P = .019) were adverse prognostic factors. The 3-year survival rates were 4%, 33%, and 38% for the PC, LR, and WL patients, respectively (P < .0001). The 3-year survival rate in the LR patients was 51% in patients without cirrhosis and 15% in patients with cirrhosis (P < .0001). CONCLUSIONS: Patients with locally unresectable tumors, distant disease, or both will continue to receive PC. Patients assigned to liver transplant WLs run the risk of not receiving a donor liver, in which case their survival is predicted to be poor. Survival after resection in a group of patients with advanced tumors is worse than that after transplantation; however, shortages of donor livers presently preclude transplantation in this population of patients.

Prognosis and management of extramammary Paget's disease and the association with secondary malignancies.

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare clinical entity and can be associated with other malignancies. We analyzed our experience for prognosis and impact of therapy on outcomes. STUDY DESIGN: We conducted a retrospective review of all patients (n = 33) with EMPD treated at a tertiary care center from 1971 to 1998. Pathologic features of EMPD, concurrent secondary malignancies, and the effect of operations on recurrence were analyzed. Overall survival was compared with that of the general population. RESULTS: Male-to-female ratio was 4:29, and median age was 70 years. Median followup was 68 months, and no patient died from EMPD. The lesion was predominantly found on the vulva (76%). Patch-like, nonconfluent growth was present in 45% of patients, and no patient had pathologic lymph nodes. The most common signs and symptoms were irritation or pruritus (73%) and rash (61%). The presence of patches, invasive tumor growth, or a second malignancy were significantly associated with a higher recurrence rate. The type of operation, either local excision or hemivulvectomy, was not related to the time to recurrence. Complete gross resection was achieved in 94% of cases. Fifty-six percent of patients had microscopically positive margin and this correlated with a significantly higher recurrence rate (p = 0.002). The tumor recurred clinically in 14 of 33 patients (42%) after a median of 152 months (range 5 to 209 months). In those patients, between one and six reexcisions were performed. In 14 of 33 patients with EMPD (42%), 16 concurrent secondary malignancies were found. Overall survival rates for EMPD patients were similar to those of the general population. CONCLUSIONS: EMPD is an infrequently diagnosed disease that is preferably managed with complete local excision and reexcisions if needed. A thorough search for frequently occurring secondary malignancies might be beneficial to provide the best outcomes for these patients.

Metastatic patterns of extremity myxoid liposarcoma and their outcome.

BACKGROUND AND OBJECTIVES: Extremity myxoid liposarcomas have a unique extrapulmonary metastatic potential. We studied the metastatic pattern of extremity liposarcomas to determine what types of posttreatment imaging may be of value in the follow-up these patients. METHODS: Twenty-two patients from a total of 128 patients with primary extremity liposarcoma were treated at a tertiary care institution for subsequent metastases from January 1981 to January 2000. Median follow-up was 45 months (range: 6-270 months). Data on these patients was prospectively collected and then retrospectively analyzed for effect of metastatic pattern and treatment on outcome. RESULTS: Of these 22 patients, extrapulmonary metastases developed in 10, combined pulmonary and extrapulmonary metastases developed in 6, and isolated pulmonary metastases developed in 6. Of the 16 patients with extrapulmonary metastases, 13 were of the myxoid subtype. Of the 49 patients with extremity myxoid liposarcomas, metastases developed in 14 (29%). The most common sites of metastases among these 14 patients include: the retroperitoneum, 10 patients (71)%; intra-abdominal extra-hepatic, 7 patients (50%); spinal/paraspinal, 6 patients (43%). Only 3 of the patients are alive and disease free and all 3 of these patients are from the subgroup of 10 patients with only extra-pulmonary metastases (2 intra-abdominal and 1 retroperitoneal). CONCLUSIONS: Extremity myxoid liposarcomas have an unusually high predilection for extra-pulmonary metastases, frequently without any pulmonary metastases. After treatment of the primary tumor, these patients should be followed with periodic chest X-ray and abdominal/pelvic computed tomography (CT) scans. Any back or neurologic complaints should prompt additional imaging of the appropriate spinal area. Consideration should be given to surgical and adjuvant treatment of metastatic disease when appropriate.

The effect of surgery and radiotherapy on outcome of anaplastic thyroid carcinoma.

BACKGROUND: Anaplastic thyroid carcinoma (ATC) is an aggressive rare tumor. We analyzed our experience for prognosis and the effect of surgery and radiotherapy on patients with ATC. METHODS: We conducted a retrospective review of all patients (n = 67) with ATC treated at a tertiary care center from 1969 to 1999. Survivor median follow-up was 51 months. Tumor and patient characteristics and therapy were assessed for effect on survival by multivariate analysis. RESULTS: Patients presented with a neck mass (99%), change of voice (51%), dysphagia (33%), and dyspnea (28%). Surgery was performed in 44 of 67 patients, with 12 complete resections. The 6-month and 1- and 3-year survival rates were 92%, 92%, and 83% after complete resection; 53%, 35%, and 0% after debulking; and 22%, 4%, and 0% after no resection, respectively (P < .0001). A radiation dose of >45 Gy improved survival as compared with a lower dose (P = .02). Multivariate analysis showed that age < or = 70 years, absence of dyspnea or dysphagia at presentation, a tumor size < or = 5 cm, and any surgical resection improved survival (P < .05). CONCLUSIONS: Candidates for surgery with curative intent for ATC are patients < or = 70 years, tumors < or = 5 cm, and no distant disease. Radiotherapy >45 Gy improves outcome.

Massive growth of a meningioma into the brachial plexus and thoracic cavity after intraspinal and supraclavicular resection. Case report and review of the literature.

Extracranial meningiomas comprise approximately 2% of all meningiomas. Involvement of peripheral nerves by meningioma, either by a primary tumor or through secondary extension of an intraaxial lesion, is a much rarer entity; there have been only two reported primary brachial plexus meningiomas and one description of secondary involvement of the brachial plexus by extension of an intraaxial lesion. Although thoracic cavity meningiomas have been described in the literature, their pathogenesis is poorly understood. The authors present the case report of a 36-year-old man who was initially treated for a thoracic spinal meningioma that infiltrated the brachial plexus. After resection, progressive and massive growth with infiltration of the brachial plexus and pleural cavity occurred over a 5-year period despite radio- and chemotherapy. The case report is followed by a review of the literature of this rare entity.