Enormous myxoid/round cell liposarcoma: A case report.

Myxoid/round cell liposarcomas (MRCLPS) are a rare soft tissue sarcoma. We report the largest sarcoma in our institutional history. We discuss the patient's surgical management and treatment of the tumor and challenges given its dimensions. Several complications arose following primary resection that were managed by a multidisciplinary team. Although MRCLPS can vary in size, large MRCLPS must be treated cautiously given the potential for complications. Additionally, multidisciplinary treatment of MRCLPS is essential in diagnosing and treating these complex cases.

Myoepithelial Carcinoma of Soft Tissue: Report of Two Cases.

CASE: A 40-year-old man was evaluated for a painful mass on his right calf, and a 36-year-old woman presented with a painless mass on her right foot. Final pathology revealed marked nuclear atypia and positivity for S100/SOX10 and AE1/AE3 confirming diagnoses of myoepithelial carcinoma. Both patients underwent surgical resection and are without evidence of local recurrence or metastatic disease at 1-year follow-up. CONCLUSION: Soft-tissue tumors presenting in the extremities warrant careful evaluation and timely histopathologic diagnosis. Myoepithelial carcinomas are rare, aggressive tumors with a propensity for local recurrence and metastasis. Treatment of these tumors should be discussed by a multidisciplinary tumor team.

Planar amorphous silicon carbide microelectrode arrays for chronic recording in rat motor cortex.

Chronic implantation of intracortical microelectrode arrays (MEAs) capable of recording from individual neurons can be used for the development of brain-machine interfaces. However, these devices show reduced recording capabilities under chronic conditions due, at least in part, to the brain's foreign body response (FBR). This creates a need for MEAs that can minimize the FBR to possibly enable long-term recording. A potential approach to reduce the FBR is the use of MEAs with reduced cross-sectional geometries. Here, we fabricated 4-shank amorphous silicon carbide (a-SiC) MEAs and implanted them into the motor cortex of seven female Sprague-Dawley rats. Each a-SiC MEA shank was 8 µm thick by 20 µm wide and had sixteen sputtered iridium oxide film (SIROF) electrodes (4 per shank). A-SiC was chosen as the fabrication base for its high chemical stability, good electrical insulation properties, and amenability to thin film fabrication. Electrochemical analysis and neural recordings were performed weekly for 4 months. MEAs were characterized pre-implantation in buffered saline and in vivo using electrochemical impedance spectroscopy and cyclic voltammetry at 50 mV/s and 50,000 mV/s. Neural recordings were analyzed for single unit activity. At the end of the study, animals were sacrificed for immunohistochemical analysis. We observed statistically significant, but small, increases in 1 and 30 kHz impedance values and 50,000 mV/s charge storage capacity over the 16-week implantation period. Slow sweep 50 mV/s CV and 1 Hz impedance did not significantly change over time. Impedance values increased from 11.6 MΩ to 13.5 MΩ at 1 Hz, 1.2 MΩ-2.9 MΩ at 1 kHz, and 0.11 MΩ-0.13 MΩ at 30 kHz over 16 weeks. The median charge storage capacity of the implanted electrodes at 50 mV/s was 58.1 mC/cm2 on week 1 and 55.9 mC/cm2 on week 16, and at 50,000 mV/s, 4.27 mC/cm2 on week 1 and 5.93 mC/cm2 on week 16. Devices were able to record neural activity from 92% of all active channels at the beginning of the study, At the study endpoint, a-SiC devices were still recording single-unit activity on 51% of electrochemically active electrode channels. In addition, we observed that the signal-to-noise ratio experienced a small decline of -0.19 per week. We also classified observed units as fast and slow repolarizing based on the trough-to-peak time. Although the overall presence of single units declined, fast and slow repolarizing units declined at a similar rate. At recording electrode depth, immunohistochemistry showed minimal tissue response to the a-SiC devices, as indicated by statistically insignificant differences in activated glial cell response between implanted brains slices and contralateral sham slices at 150 µm away from the implant location, as evidenced by GFAP staining. NeuN staining revealed the presence of neuronal cell bodies close to the implantation site, again statistically not different from a contralateral sham slice. These results warrant further investigation of a-SiC MEAs for future long-term implantation neural recording studies.

Hip Arthroplasty Outcomes in Patients with Metastatic Bone Disease.

Background/Objective: The hip is a common location for metastatic bone disease (MBD) and surgical intervention is often indicated to relieve pain and improve function. MBD of the hip is usually treated with hemiarthroplasty or with total hip arthroplasty if there are acetabular lesions. As treatment for metastatic disease evolves and patients may expect to live longer after diagnosis, further evaluation of the complications and functional outcomes associated with hip arthroplasty for MBD are necessary. Methods: This was a retrospective review of patients who underwent hip arthroplasty for MBD at a single institution between 2007 and 2021. Outcomes included rates of reoperation, complications, and overall survival. Results: Ninety-three cases in 91 patients were included. Total hip arthroplasty (THA) was performed in 52 cases (55.9%), hemiarthroplasty in 15 (16.1%), and complex arthroplasty, including proximal femur replacement or THA with complex acetabular reconstruction, was performed in 26 (28%). There were 11 reoperations in five patients and six dislocations. Median survival was 10.4 months and one-year overall survival was 53.3%. There was a significant increase in the proportion of patients who were able to ambulate independently (35.2% vs 17.6%; p=0.02) and a significant decrease in patients confined to a wheelchair (18.7% vs 3.3%; p=0.045) after surgery. Conclusions: Hip arthroplasty for MBD leads to relatively low rates of complications and reoperations in this population known to have high postoperative morbidity and mortality. Hip arthroplasty provides the majority of MBD patients with a durable reconstruction that exceeds their lifespan and enables them to return to an acceptable level of function.

Intra-Articular Nodular Fasciitis of the Knee, A Rare Clinical Presentation and Histological Diagnosis: A Case Report.

Introduction: Nodular fasciitis is a rare, benign soft tissue lesion that can prove to be difficult to diagnose, especially when intra-articular. Case presentation: A 17-year-old female softball player presents with several year history of right knee pain and swelling initially attributed to patellar maltracking refractory to non-operative and operative management. Management and Outcomes: Initial pathology suggested tenosynovial giant cell tumor; however, further tissue diagnosis revealed nodular fasciitis, which was eventually resected. Conclusion: Intra-articular nodular fasciitis of the knee is rare and may easily be misdiagnosed due to its nonspecific clinical presentation. Careful histological examination can aid in diagnosis. Nodular fasciitis should be considered in the differential diagnoses for intra-articular lesions of the knee joint.

In Vitro Pharmacological Modulation of PIEZO1 Channels in Frontal Cortex Neuronal Networks.

PIEZO1 is a mechanosensitive ion channel expressed in various organs, including but not limited to the brain, heart, lungs, kidneys, bone, and skin. PIEZO1 has been implicated in astrocyte, microglia, capillary, and oligodendrocyte signaling in the mammalian cortex. Using murine embryonic frontal cortex tissue, we examined the protein expression and functionality of PIEZO1 channels in cultured networks leveraging substrate-integrated microelectrode arrays (MEAs) with additional quantitative results from calcium imaging and whole-cell patch-clamp electrophysiology. MEA data show that the PIEZO1 agonist Yoda1 transiently enhances the mean firing rate (MFR) of single units, while the PIEZO1 antagonist GsMTx4 inhibits both spontaneous activity and Yoda1-induced increase in MFR in cortical networks. Furthermore, calcium imaging experiments revealed that Yoda1 significantly increased the frequency of calcium transients in cortical cells. Additionally, in voltage clamp experiments, Yoda1 exposure shifted the cellular reversal potential towards depolarized potentials consistent with the behavior of PIEZO1 as a non-specific cation-permeable channel. Our work demonstrates that murine frontal cortical neurons express functional PIEZO1 channels and quantifies the electrophysiological effects of channel activation in vitro. By quantifying the electrophysiological effects of PIEZO1 activation in vitro, our study establishes a foundation for future investigations into the role of PIEZO1 in neurological processes and potential therapeutic applications targeting mechanosensitive channels in various physiological contexts.

Evaluation of Absolute Neutrophil Count in the Perioperative Setting of Sarcoma Resection.

Introduction: Limb salvage surgery (LSS) is the preferred surgical treatment for bone sarcomas. Preoperatively, many patients receive chemotherapy and may develop neutropenia. No study has evaluated the effect of a low preoperative absolute neutrophil count (ANC) on postoperative outcomes following LSS. Methods: This was a retrospective review of 114 patients who underwent LSS for bone sarcoma from 2010 to 2020. Preoperative lab values were analyzed by logistic regression to identify the risk of developing surgical complications within 30 days, surgical site infection (SSI), and reoperation. Results: Three (2.6%) patients experienced a surgical complication within 30 days. Twelve (10.53%) patients experienced postoperative SSI. Twenty-nine (25.4%) required reoperation. Preoperative ANC was not a significant predictor of surgical complications within 30 days, SSI, or reoperation. The only independent predictor of worse overall survival was the presence of a pathologic fracture at the time of surgery. Conclusion: This is the first study to evaluate preoperative ANC on postoperative outcomes following LSS. We report no significant differences in surgical complications within 30 days, SSI, or reoperation with low preoperative ANC. Future studies with larger cohorts of neutropenic patients are needed to evaluate these outcomes, as our cohort had very few neutropenic patients due to selection bias.

Macrofungal Mediated Biosynthesis of Silver Nanoparticles and Evaluation of Its Antibacterial and Wound-Healing Efficacy.

Recently, the utilization of biological agents in the green synthesis of nanoparticles has been given interest. In this study, silver nanoparticles were synthesized from an aqueous extract of macrofungus (mushroom), namely Phellinus adamantinus, in a dark room using 20 µL of silver nitrate. Biosynthesized silver nanoparticles were confirmed by analyzing them using a UV-Vis (ultraviolet-visible) spectrophotometer. The synthesized silver nanoparticles were optimized at different pH and temperatures with various dosages of AgNO3 (silver nitrate) and fungal extracts. The synthesized AgNPs (silver nanoparticles) were characterized using TEM (transmission electron microscopy) and EDX (energy-dispersive X-ray) analyses, which confirmed the presence of silver nanoparticles. The size of the nanosilver particles was found to be 50 nm with higher stability. The mycosynthesized AgNPs showed effective antibacterial activity against strains of Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (E. coli and Pseudomonas aeruginosa) bacteria. The minimum inhibitory concentration (MIC) was found to be 3.125 µg/mL by MIC assay. The MTT assay (3-[4,5-dimethylthiazol-2-yl] 2,5-diphenyl-2H-tetrazolium bromide) was performed to study cytotoxicity, and reduced cell viability was recorded at 100 µg/mL. Silver-Polygalacturonic acid-Polyvinyl alcohol ((Ag-PGA)-PVA) nanofiber was prepared using the electrospinning method. The in vitro wound scratch assay was demonstrated to study the wound-healing efficacy of the prepared nanofiber. The wound-healing efficacy of the AgNP-incorporated nanofiber was found to be 20% after 24 h. This study will lay a platform to establish a unique route to the development of a novel nanobiomaterial and its application in antibacterial and wound-healing therapy.

Does Perioperative Radiation Affect Implant Survivorship of Primary Total Hip Arthroplasty in the Setting of Metastatic Bone Disease?

Background: Metastatic bone disease (MBD) commonly affects the hip and surgical intervention including total hip arthroplasty (THA) is often indicated to treat the joint and improve function. Patients with metastatic cancer often receive radiotherapy, and orthopaedic oncologists must consider surgical risks with operating on irradiated bone and soft tissue. We evaluated surgical outcomes and implant survival (IS) of titanium acetabular components and femoral components in patients treated for MBD in the setting of perioperative radiation. Methods: This was a retrospective review of patients who underwent THA for MBD at 3 institutions between 2017 and 2021. Outcomes included rates of reoperation, complications, IS, and overall survival. Results: Forty-six patients who received primary THA for MBD were included in the study. Twenty patients (43.5%) received perioperative radiation for MBD. Six postoperative complications including one superficial wound infection, 2 dislocations, 2 pathologic fractures, and one aseptic acetabular component loosening led to 5 reoperations. There were no significant differences in postoperative outcomes, reoperation after THA, and IS based on radiotherapy status. Conclusions: To our knowledge, this is the first paper evaluating primary THA outcomes and IS between patients who receive perioperative radiation for MBD to the hip and those who do not. As surgical management is a crucial part of the treatment in alleviating pain and disability in patients with MBD, we continue to recommend THA for patients who received radiation at the operative site.

An Unusual Case of Clear Cell Chondrosarcoma With Early Metastatic Recurrence.

We present a case of a 58-year-old male who presented following 4 months of progressively worsening right upper extremity pain. Initial pathology demonstrated pleomorphic chondroblasts with increased mitotic activity indicating an intermediate grade (Grade 2) clear cell chondrosarcoma of the proximal humerus. Following surgical resection, the primary lesion demonstrated aggressive behavior and early metastasis to the cervical and thoracic spine. The patient unfortunately expired 30 months after initial presentation. Although clear cell chondrosarcoma has been historically regarded as low grade, we present a unique example of an aggressive clinical course of clear cell chondrosarcoma.

Comparative molecular profiling of multidrug-resistant Pseudomonas aeruginosa identifies novel mutations in regional clinical isolates from South India.

Objectives: We sought to analyse the antibiotic susceptibility profiles and molecular epidemiology of MDR clinical Pseudomonas aeruginosa isolates from South India using non-MDR isolates as a reference. Methods: We established a comprehensive clinical strain library consisting of 58 isolates collected from patients across the South Indian state of Kerala from March 2017 to July 2019. The strains were subject to antibiotic susceptibility testing, modified carbapenem inactivation method assay for carbapenemase production, PCR sequencing, comparative sequence analysis and quantitative PCR of MDR determinants associated with antibiotic efflux pump systems, fluoroquinolone resistance and carbapenem resistance. We performed in silico modelling of MDR-specific SNPs. Results: Of our collection of South Indian P. aeruginosa clinical isolates, 74.1% were MDR and 55.8% were resistant to the entire panel of antibiotics tested. All MDR isolates were resistant to levofloxacin and 93% were resistant to meropenem. We identified seven distinct, MDR-specific mutations in nalD, three of which are novel. mexA was significantly overexpressed in strains that were resistant to the entire test antibiotic panel while gyrA and gyrB were overexpressed in MDR isolates. Mutations in fluoroquinolone determinants were significantly associated with MDR phenotype and a novel GyrA Y100C substitution was observed. Carbapenem resistance in MDR isolates was associated with loss-of-function mutations in oprD and high prevalence of NDM (blaNDM-1) within our sample. Conclusions: This study provides insight into MDR mechanisms adopted by P. aeruginosa clinical isolates, which may guide the potential development of therapeutic regimens to improve clinical outcomes.

Rare Dedifferentiated Periosteal Chondrosarcoma with 11-Year Metastatic Relapse: A Case Report.

A 50-year-old man presented for evaluation of a periscapular mass. Biopsy suggested a low-grade chondrosarcoma; however, the resected specimen revealed a grade 2 chondrosarcoma with a low-grade dedifferentiated mesenchymal component. The mass multiply recurred as chondrosarcoma without a dedifferentiated component before the patient developed lung metastases of chondrosarcoma without a dedifferentiated component 11 years after the initial diagnosis and died of disease. This is one of the first reported cases of a dedifferentiated chondrosarcoma with low-grade dedifferentiated component. While overall prognosis may be better than in typical dedifferentiated chondrosarcoma, this tumor demonstrated numerous local recurrences as well as metastasis.

The effect of timing between preoperative embolization and surgery: A retrospective analysis of hypervascular bone metastases.

BACKGROUND AND OBJECTIVES: The optimal timing between preoperative embolization of hypervascular metastatic bone lesions and surgery has yet to be established. Our analysis sought to evaluate embolization timing impacts blood loss, transfusion risk, and operative time in patients with hypervascular primary tumors. METHODS: We identified patients with renal cell (RCC) or thyroid carcinoma undergoing surgery between 1992 and 2023. Patients were segregated into the following cohorts: (1) no embolization preoperatively, (2) surgery <24 h of embolization, and (3) surgery >24 h after embolization. Multivariate logistic regression analyses were performed to assess the effect of embolization timing while controlling for confounding variables. RESULTS: No differences were seen in all evaluated outcomes between immediate and delayed embolization cohorts. No differences in estimated blood loss were seen between the immediate (OR: 0.685, 95% CI: 0.159-2.949; p = 0.611) and delayed (OR: 0.568, 95% CI: 0.093-3.462; p = 0.539) surgery cohorts compared with patients without embolization. Surgery >24 h after embolization was not associated with a higher risk of prolonged operative time (OR: 13.499, 95% CI: 0.832-219.146; p = 0.067). CONCLUSIONS: These findings suggest that surgery may be safely delayed beyond 24 h from embolization without a higher risk of bleeding. In appropriately selected cohorts, embolization may not be needed preoperatively.

Opiate use after total hip arthroplasty for metastatic bone disease.

OBJECTIVES: To investigate post-operative opioid use following a total hip arthroplasty (THA) in metastatic bone disease (MBD) patients and identify factors associated with post-operative opioid use at 6 weeks and 90 days. BACKGROUND: MBD commonly affects the hip, and surgical intervention including THA may be indicated for pain relief or to improve function. Following THA, patients are often prescribed short courses of opioids for post-operative pain relief. No study has evaluated opiate use following THA in patients for MBD. METHODS: This was a retrospective review of patients using opioids preoperatively who underwent primary THA for MBD at two institutions between 2009 and 2022. Preoperative and post-operative opioid usages, respectively, at 6 weeks and 90 days were quantified through calculating daily morphine milligram equivalents (MMEs) and compared using the sign test. Factors associated with post-operative opioid use at 6 weeks and 90 days were compared using χ2 test or Fisher's exact test as appropriate. RESULTS: Nineteen THA and 11 THA with complex acetabular reconstruction were included. At 6 weeks, 26 (86.7 percent) patients were utilizing opiates, and at 90 days, 23 (76.7 percent) patients were utilizing opiates. There was a statistically significant difference between median daily preoperative MME compared to daily MME at 90 days (p < 0.001). The only statistically significant association with opioid use at 90 days was opioid use at 6 weeks. CONCLUSION: To our knowledge, this is the first paper evaluating post-operative opioid use following primary THA in MBD patients. After THA in the setting of MBD, patients exhibit decreased post-operative opioid use. Future studies with larger cohorts should be conducted to characterize post-operative opioid use following joint arthroplasty in MBD patients.

Patient-reported outcome tools in musculoskeletal oncology.

Patient-reported outcomes (PRO) are collected directly from the patient and have become increasingly utilized in the clinical setting and in clinical research. In musculoskeletal oncology patients, a number of patient-reported outcomes measures (PROM) have been developed and investigated to evaluate functional outcomes and health-related quality of life in these patients. With the growing evidence for PROM in musculoskeletal oncology patients, PROM should be considered for the clinical care of these patients.

A Rare Location of Osteosarcoma in the Cuboid Bone: A Case Report.

CASE: In this case report, we describe a patient with left foot pain whose magnetic resonance imaging revealed a destructive tumor of the left cuboid bone. A biopsy of the tumor confirmed an osteoblastic osteosarcoma of the cuboid, and the patient was treated with chemotherapy followed by a below-the-knee amputation. CONCLUSION: There are only a handful of cases reporting osteosarcoma of the cuboid bone, and challenges remain in properly diagnosing the lesion to recommend the best course of treatment.

Association between neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and survival in undifferentiated pleomorphic sarcoma (NLR, PLR, and overall survival in UPS).

BACKGROUND AND OBJECTIVES: Cancer-related inflammation has been shown to be a driver of tumor growth and progression, and there has been a recent focus on identifying markers of the inflammatory tumor microenvironment. Neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) are inflammatory indices that have been identified as prognostic biomarkers in various malignancies. However, there is limited and conflicting data regarding their prognostic value in soft tissue sarcoma (STS) and specifically in undifferentiated pleomorphic sarcoma (UPS). METHODS: This was a retrospective review of patients who underwent surgical treatment for primary UPS from 1993 to 2021. Cutoff values for NLR and PLR were determined by receiver operating curve analysis. Cox proportional hazards regression was used to determine prognostic factors on univariate and multivariate analysis. RESULTS: Eighty-six patients were included. The optimal cutoff value was 3.3 for NLR and 190 for PLR. Both high NLR (HR 2.44; 95% CI 1.29-4.63; p = 0.005) and high PLR (HR 1.99; 95% CI 1.08-3.67, p = 0.02) were associated with worse OS on univariate analysis. On multivariate analysis, metastasis at presentation and radiotherapy were independently predictive of OS, but high NLR (HR 1.30; 95% CI 0.64-2.98; p = 0.41) and high PLR (HR 1.63; 95% CI 0.82-3.25; p = 0.17) were not predictive of survival. CONCLUSIONS: High pre-treatment NLR and PLR were associated with decreased overall survival but were not independent predictors of survival in patients undergoing resection for UPS. Until additional prospective studies can be done, survival outcomes are best predicted using previously established patient- and tumor-specific factors.

Evaluation of Local Recurrence and Diagnostic Discordance in Chondrosarcoma Patients Undergoing Preoperative Biopsy.

BACKGROUND/AIM: Preoperative biopsy of chondroid lesions has demonstrated discordance between biopsy grade and surgical resection grade. Furthermore, there is evidence to suggest risk of tumor contamination during biopsy. We evaluated our large chondrosarcoma institutional cohort to compare the rates of local recurrence based on pre-surgical biopsy, as well as other tumor characteristics and disease-related outcomes. PATIENTS AND METHODS: This was a retrospective review of patients who underwent surgical resection for chondrosarcoma at our Institution between 2005 and 2020. Outcomes included rates of local recurrence, metastasis, and overall survival. RESULTS: No significant differences were found in local recurrence and recurrence-free survival in cases of pre-operative biopsy. Thirteen (28.2%) patients had discordance between histological grade on biopsy and resection. Seven (63.6%) patients with dedifferentiation present on final resection were not identified on biopsy. The only independent predictor of recurrence-free survival and metastasis-free survival was the presence of dedifferentiation on resection. CONCLUSION: To our knowledge, this is the first study evaluating risk of local recurrence in the setting of pre-surgical biopsy in chondrosarcoma patients. Although pre-operative biopsy may contaminate biopsy tracts, appropriate surgical planning and final resection results in no difference in local recurrence rates in this cohort. However, discordance rates between preoperative biopsy and resected specimen must be considered while determining clinical treatment.

Epithelioid hemangioendothelioma of the distal lower extremity and the role of radiotherapy: A report of two cases.

We report two cases of epithelioid hemangioendothelioma (EHE) in the distal lower extremity. Our first patient had unicentric EHE of the left os calcis initially treated with an intralesional procedure; however, later developed two recurrences which were managed with radiation therapy. Our second patient had multicentric EHE of the distal tibia and fibula managed with primary radiation therapy. Although EHE is typically treated with wide resection or an intralesional procedure, we present two cases of EHE in the distal lower extremity to discuss the therapeutic role of radiation therapy in the management of distal EHE.

Radiation osteitis: incidence and clinical impact in the setting of radiation treatment for soft tissue sarcoma.

OBJECTIVE: Radiotherapy is an important component of soft tissue sarcoma management. Radiation osteitis is a common radiographic finding identified in the setting of radiotherapy on magnetic resonance imaging (MRI). This study aims to identify the incidence of radiation osteitis in patients who received radiotherapy for soft tissue sarcoma and if a further workup, including a biopsy, was performed for concerning MRI findings. MATERIALS AND METHODS: Medical records of patients with soft tissue sarcoma who received radiotherapy from 2008 to 2020 were retrospectively reviewed. Patients with at least one MRI of the sarcoma site following radiotherapy and information regarding radiotherapy treatments were included. MRIs of these patients were reviewed for the presence of radiation osteitis by two musculoskeletal radiologists. The clinical course of these patients including biopsy for concerning MRI findings, local recurrence, and metastasis was recorded. RESULTS: Thirty soft tissue sarcoma patients who received radiation for soft tissue sarcoma were included. Radiation osteitis was present in 18 patients. The time to osteitis present on MRI following radiotherapy completion was a median of 4.5 months. Biopsy for concerning MRI findings was performed in eight patients, five for local recurrence, and three for regional osseous metastasis. Three patients had confirmed osseous metastases. CONCLUSION: Although radiation osteitis is often a benign imaging finding, it can be difficult to discern these lesions from potentially malignant sites of disease. We recommend multidisciplinary management of soft tissue sarcoma at sarcoma centers to appropriately identify benign from malignant lesions and decide the necessity of a biopsy.