Periosteal Ewing Sarcoma with Distant Metastases: Report of Two Patients and Review of the Literature.

Periosteal Ewing sarcoma (ES) is an exceedingly rare topographic subtype of the ES. To our knowledge, only 60 patients have been reported in the medical English language literature. It predominantly affects men in the second decade of life and arises in the long tubular bone diaphysis. PES rarely develops distant metastases. We report two patients of this rare ES location that were found on the distal tibial shaft and proximal femoral diaphysis of a 21-year-old man and an 8-year-old boy, respectively. Both patients were treated with neoadjuvant chemotherapy, wide resection, and adjuvant chemotherapy. One of our patients had lung metastases at the time of diagnosis and died 5 years later. The other patient presented intramedullary humeral bone metastasis 19 years after diagnosis. There has been no evidence of disease in the 26 years of follow-up. Close follow-up of periosteal ES is recommended because distant metastases may exceptionally occur, even several years after diagnosis.

Effectiveness of specific scapular therapeutic exercises in patients with shoulder pain: a systematic review with meta-analysis.

Background: Therapeutic exercise has been considered a useful tool to rehabilitate shoulder pain, namely through its influence on scapular dynamics. Accordingly, the effectiveness of scapular therapeutic exercise needs to be explored. The present study aims to evaluate the effectiveness of scapular therapeutic exercises in shoulder pain and to identify the most effective exercise type (focal or multijoint) and ways of delivering them (as dose and progression). Methods: Search was conducted at EMBASE, Cochrane Library, MEDLINE via PubMed, Web of Science, PEDro (Physiotherapy Evidence Database), and trial registration databases. The meta-analysis considered randomized controlled/crossover trials that compared the effect of scapular exercises against other types of intervention in the shoulder pain, shoulder function, scapular motion, and/or muscular activity. The risk of bias was assessed through the PEDro scale. Results: From the 8318 records identified, 8 (high to low risk of bias- scoring from 4 to 8 on the PEDro scale) were included. The overall data, before sensitivity analysis, indicated that the scapular therapeutic exercises are: a) more effective than comparators in improving shoulder function (standardized mean difference [SMD] = 0.52 [95% Cl: 0.05, 0.99], P = .03, I2 = 76%); and b) as effective as comparators in reducing shoulder pain (SMD = 0.32 [95% Cl: -0.09, 0.73], P = .13, I2 = 70%). Subgroup analysis revealed that scapular exercises are more effective in improving shoulder function when the program duration is equal to or higher than 6 weeks (SMD = 0.43 [95% Cl: 0.09, 0.76] P = .01, I2 = 21%) and/or when the maximum number of exercise repetitions per session is lower than 30 (SMD = 0.79 [95% Cl: 0.15, 1.42], P = .01, I2 = 77%). Only 1 study considered scapular motion as an outcome measure, revealing therapeutic exercise effectiveness to improve scapular range of motion. Conclusions: Intervention programs involving scapular therapeutic exercises are effective in improving shoulder function, presenting benefits when performed for 6 or more weeks and/or when used up to a maximum of 30 repetitions per exercise, per session.

Lack of Specific Immune Response after Five Doses of mRNA SARS-CoV-2 Vaccine in a Patient with CD4+ T-Cell Lymphopenia but Preserved Responses to CMV.

Immunogenicity of SARS-CoV-2 mRNA vaccines is highly heterogeneous in patients with inborn errors of immunity (IEIs). This case report analyzes the immune response to mRNA COVID-19 two-dose primary vaccination followed by three boosters in an IEI patient with marked CD4+ T-cell cytopenia and diminished thymic output, in comparison with that raised against latent, chronic cytomegalovirus (CMV) infection. Serum IgG antibodies anti-spike (S) protein of SARS-CoV-2 and anti-CMV were both determined by chemiluminescent microparticle immunoassays (CMIAs). SARS-CoV-2 and CMV memory CD4+ T-cell responses were simultaneously evaluated in vitro using an activation-induced marker (AIM) assay via multicolor flow cytometry. Throughout the 2-year follow-up that included the administration of five doses of SARS-CoV-2 mRNA vaccines, cellular anti-SARS-CoV-2-specific responses remained consistently negative, with extremely weak humoral responses, while the patient showed in vitro persistent CD4+ T-cell reactivity to CMV peptides and high-IgG CMV-specific titers. The assessment of immune responses to vaccines and prevalent viruses is essential in IEI patients in order to take adequate preventive measures.

Characterisation of new in vitro models and identification of potentially active drugs in angiosarcoma.

Angiosarcoma is a rare soft tissue sarcoma originating from endothelial cells. Given that current treatments for advanced disease have shown limited efficacy, alternative therapies need to be identified. In rare diseases, patient-derived cell models are crucial for screening anti-tumour activity. In this study, cell line models were characterised in 2D and 3D cultures. The cell lines' growth, migration and invasion capabilities were explored, confirming them as useful tools for preclinical angiosarcoma studies. By screening a drug library, we identified potentially effective compounds: 8-amino adenosine impacted cell growth and inhibited migration and invasion at considerably low concentrations as a single agent. No synergistic effect was detected when combining with paclitaxel, gemcitabine or doxorubicin. These results suggest that this compound could be a potentially useful drug in the treatment of AGS.

Midfoot width changes after first metatarsal osteotomy in hallux valgus surgery: A biomechanical effect?

Hallux valgus is a challenging pathology characterized by a valgus deformity in the metatarsophalangeal area of the first ray. The aim of this study was to analyze the influence of first metatarsal osteotomy on the relationship between midfoot bones in patients with hallux valgus. The sample consisted of patients from the orthopedics and traumatology outpatient clinic who underwent surgical treatment for hallux valgus. Preoperative and postoperative X-rays were compared regarding the width of the midfoot and the tarsometatarsal joint. The sample consisted of 17 women, with 22 feet assessed in each group. The distance from the medial cuneiform to the cuboid, the distance from the intermediate cuneiform to the cuboid, the distance between the first and fifth metatarsals, and the distance between the second and fifth metatarsals reduced significantly between pre- and postoperative assessments. Hallux valgus correction through osteotomy of the first metatarsal leads to a structural change in the midfoot. Further studies should determine whether these changes persist over time.

Correction: Implementation of digital health in rural populations with chronic musculoskeletal conditions: A scoping review protocol.

[This corrects the article DOI: 10.1371/journal.pone.0291638.].

Scapular muscle dynamic stiffness of asymptomatic subjects and subjects with chronic shoulder pain, at rest and isometric contraction conditions.

Muscle stiffness had a crucial role in joint stability, particularly, at the shoulder complex. Although changes in upper trapezius muscle stiffness have been described for shoulder pain, contradictory findings have been obtained. Also, existing data regarding scapular muscles are, majorly, about trapezius. Myotonometry is a method used to assess stiffness; however, the reliability values of scapular muscle stiffness through this method have not been assessed in shoulder pain conditions. The present study aims to compare scapular muscles' stiffness (trapezius, serratus anterior, and levator scapulae) between subjects with and without chronic shoulder pain and to evaluate the related test-retest reliability. Twenty-two symptomatic and twenty-two asymptomatic subjects participated in a cross-sectional study. The dynamic muscular stiffness of scapular muscles, at rest and during an isometric contraction, was measured bilaterally with myotonometry, in two moments. The differences in bilateral averaged values between symptomatic and asymptomatic subjects and the effect of the group (group presenting pain in the dominant or non-dominant side, and asymptomatic group) and of the limb (unilateral painful or asymptomatic limb, and bilateral asymptomatic limbs) were investigated. Test-retest intra-rater reliability was determined. An effect of the group was observed at rest, for middle trapezius stiffness, and during contraction, for middle and lower trapezius stiffness. For middle trapezius, increased values were observed in the group presenting pain in non-dominant side comparing to both groups or to group presenting pain in dominant side. The intraclass correlation coefficient, majorly, ranged between 0.775 and 0.989. Participants with pain in the non-dominant side presented an increased middle trapezius' stiffness. Globally, high reliability was observed for scapular muscles dynamic stiffness.

Physiotherapists' barriers and facilitators to the implementation of a behaviour change-informed exercise intervention to promote the adoption of regular exercise practice in patients at risk of recurrence of low back pain: a qualitative study.

BACKGROUND: Recurrences of low back pain (LBP) are frequent and associated with high levels of disability and medical costs. Regular exercise practice may be an effective strategy to prevent recurrences of LBP, however, the promotion of this behaviour by physiotherapists seems to be challenging. This study aims to explore physiotherapists' perceived barriers and facilitators to the implementation of a behaviour change-informed exercise intervention to promote the adoption of regular exercise practice by patients at risk of recurrence of low back pain. METHODS: Two focus groups with primary healthcare physiotherapists were conducted, based on a semi-structured interview schedule informed by the Behaviour Change Wheel, including the Capability, Opportunity, Motivation-Behaviour (COM-B) model and the Theoretical Domains Framework (TDF). All focus groups were held through videoconference, audio and video recorded and transcribed verbatim. A deductive content analysis, using a coding matrix based on the COM-B and TDF, was performed by two independent researchers. A third researcher was approached to settle disagreements. RESULTS: In total, 14 physiotherapists participated in the focus groups. The analysis revealed a total of 13 barriers (4 COM-B components and 7 TDF domains) and 23 facilitators (5 COM-B and 13 TDF) to physiotherapists' implementation of a behaviour change-informed exercise intervention. The most common barriers were the lack of skills and confidence to implement the proposed intervention. These were explained by the fact that it differs from the usual practice of most participants and requires the learning of new skills applied to their contexts. However, for those who had already implemented other similar interventions or whose rationale is aligned with the new intervention, there seemed to exist more positive determinants, such as potential benefits for physiotherapists and the profession, improvement of quality of care and willingness to change clinical practice. For others who did not previously succeed in implementing these types of interventions, more context-related barriers were mentioned, such as lack of time to implement the intervention, schedule incompatibilities and lack of material and human resources. CONCLUSIONS: This study identified modifiable barriers and facilitators to physiotherapists' implementation of a behaviour change-informed exercise intervention for patients at risk of recurrence of LBP in primary healthcare. The findings of this study will allow the systematic and theory-based development of a behaviour change-informed training programme, aimed at physiotherapists and supporting the successful implementation of the exercise intervention.

Economic evaluation of percutaneous cryoablation vs conventional surgery in extra-abdominal desmoid tumours in the Spanish healthcare system.

BACKGROUND: Desmoid tumours (DTs) or deep fibromatosis are benign soft-tissue tumours, sometimes locally aggressive, requiring intervention on some cases. Surgery has been the gold standard, but new less invasive techniques such as percutaneous cryoablation have proved their effectiveness, reducing health resources and complications. The study aimed to compare the total cost of percutaneous cryoablation and conventional surgery for patients with extra-abdominal and/or abdominal wall DTs, candidates for local ablative treatment in Spain. METHODS: A cost-analysis model was developed. An expert panel provided data about resource consumption for the percutaneous cryoablation technique and validated the epidemiology used for target population estimation. Unitary resources cost (€ 2022) derived from local cost databases. A retrospective analysis of 54 surgical cases in 3 Spanish hospitals was performed to estimate the cost of conventional surgery based on the cost of the Diagnosis-Related group (DRG) codes identified on this patient sample, weighted by each DRG proportion. The total cost for each alternative included intervention cost and complications cost, considering debridement required in 4.5% of cases with percutaneous cryoablation and minor surgery for surgical site infection in 18.0% for conventional surgery. RESULTS: The total cost for percutaneous cryoablation (€ 5774.78/patient-year) was lower than the total cost for conventional surgery (€ 6780.98/patient-year), yielding cost savings up to € 80,002 in 1 year for the entire cohort of 80 patients with DTs eligible for intervention estimated in Spain. One-way sensitivity analyses confirmed the results' robustness. CONCLUSION: Percutaneous cryoablation versus conventional surgery would yield cost savings for the management of DT patients in Spain. CRITICAL RELEVANCE STATEMENT: This manuscript provides insight into the economic impact derived from the savings related to the use of percutaneous cryoablation for desmoid-type tumours from the perspective of the Spanish National Healthcare System, providing useful information for the health decision-making process. KEY POINTS: • Desmoid tumours are locally aggressive and may require local therapy. • Percutaneous cryoablation procedure is less invasive than the conventional surgery. • Cost comparison shows savings associated to percutaneous cryoablation use.

Recurrent and metastatic cellular cutaneous fibrous histiocytoma: A case report and literature review.

Cutaneous fibrous histiocytoma (FH) is considered a benign dermal tumor. The cellular variant is rare and poorly documented. Besides presenting a high risk of local recurrence, it has a low but serious metastatic potential. We present a case of metastatic cellular FH and also review the literature on this tumor, given its unusual metastatic development. A 47-year-old male patient presented with a lesion in the anterior surface of the right thigh, which has been present since adolescence but had grown during last year. Anatomopathological evaluation revealed a cellular FH, and the lesion was completely removed. Six months later, tumor recurrence with multiple compartment muscle involvement and pulmonary metastasis were detected. Both lesions were completely resected and after 3 years of follow-up, the patient is asymptomatic and free of the disease. We conclude that FH should be carefully sampled to detect variants with high local recurrence rates or with some metastatic risk such as the cellular one. We recommend wide surgical resection and a close follow-up including chest x-rays or thorax computed tomography (CT) in all cellular FH cases with local recurrence.

Minimal Intervention of Patient Education for Low Back Pain: A Systematic Review With Meta-analysis.

OBJECTIVE: To explore the effects of minimal intervention of patient education (MIPE) for reducing disability and pain intensity in patients with low back pain (LBP). DESIGN: Intervention systematic review with meta-analysis of randomized controlled trials. LITERATURE SEARCH: We searched the MEDLINE, Embase, CENTRAL, CINAHL, and PsycINFO databases from inception to May 2023. STUDY SELECTION CRITERIA: Trials comparing MIPE, consisting of a single session of patient education, to no or other interventions in patients with LBP. DATA SYNTHESIS: Random effects meta-analysis was conducted where possible. A noninferiority margin of 5 points (0-100 scale) was considered for noninferiority hypotheses. We assessed risk of bias using the revised Cochrane risk-of-bias tool (RoB 2), and certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. RESULTS: A total of 21 trials were included. There were no differences between MIPE and no intervention for effects on disability and pain intensity. There was low-certainty evidence that MIPE had inferior effects on short-term disability (mean difference = 3.62; 95% CI: 0.85, 6.38; 15 trials; n = 3066; I2 = 75%) and pain intensity (mean difference = 9.43; 95% CI: 1.31, 17.56; 10 trials; n = 1394; I2 = 90%) than other interventions. No differences were found for subsequent time points. CONCLUSION: As an intervention delivered in isolation, and without tailoring (ie, one-size-fits-all intervention), MIPE on average did not provide benefits for reducing disability and pain intensity over no or other interventions. We encourage clinicians to consider using additional/other or more tailored treatments when helping people manage LBP. J Orthop Sports Phys Ther 2024;54(2):1-13. Epub 16 November 2023. doi:10.2519/jospt.2023.11865.

Outcomes of Long Bones Treated With Carbon-Fiber Nails for Oncologic Indications: International Multi-institutional Study.

BACKGROUND: Intramedullary nail fixation is commonly used for prophylactic stabilization of impending and fixation of complete pathological fractures of the long bones. However, metallic artifacts complicate imaging evaluation for bone healing or tumor progression and postoperative radiation planning. Carbon-fiber implants have gained popularity as an alternative, given their radiolucency and superior axial bending. This study evaluates incidences of mechanical and nonmechanical complications. METHODS: Adult patients (age 18 years and older) treated with carbon-fiber nails for impending/complete pathological long bone fractures secondary to metastases from 2013 to 2020 were analyzed for incidences and risk factors of mechanical and nonmechanical complications. Mechanical complications included aseptic screw loosening and structural failures of host bone and carbon-fiber implants. Deep infection and tumor progression were considered nonmechanical. Other complications/adverse events were also reported. RESULTS: A total of 239 patients were included; 47% were male, and 53% were female, with a median age of 68 (IQR, 59 to 75) years. Most common secondary metastases were related to breast cancer (19%), lung cancer (19%), multiple myeloma (18%), and sarcoma (13%). In total, 17 of 30 patients with metastatic sarcoma received palliative intramedullary nail fixation for impending/complete pathological fractures, and 13 of 30 received prophylactic nail stabilization of bone radiated preoperatively to manage juxta-osseous soft-tissue sarcomas, where partial resection of the periosteum or bone was necessary for negative margin resection. 33 (14%) patients had complications. Mechanical failures included 4 (1.7%) structural host bone failures, 7 (2.9%) implant structural failures, and 1 (0.4%) aseptic loosening of distal locking screws. Nonmechanical failures included 8 (3.3%) peri-implant infections and 15 (6.3%) tumor progressions with implant contamination. The 90-day and 1-year mortalities were 28% (61/239) and 53% (53/102), respectively. The literature reported comparable failure and mortality rates with conventional titanium treatment. CONCLUSIONS: Carbon-fiber implants might be an alternative for treating impending and sustained pathological fractures secondary to metastatic bone disease. The seemingly comparable complication profile warrants further cohort studies comparing carbon-fiber and titanium nail complications.

Effectiveness of Neural Mobilisation on Pain Intensity, Functional Status, and Physical Performance in Adults with Musculoskeletal Pain - A Systematic Review with Meta-Analysis.

OBJECTIVE: To investigate up-to-date evidence of the effectiveness of neural mobilisation techniques compared with any type of comparator in improving pain, function, and physical performance in people with musculoskeletal pain. DATA SOURCES: The following sources were consulted: PubMed, Web of Science, CENTRAL, CINAHL, Scopus, and PEDro databases; scientific repositories; and clinical trial registers. The last search was performed on 01/06/2023. METHODS: Two reviewers independently assessed the studies for inclusion. We included randomised, quasi-randomised, and crossover trials on musculoskeletal pain in which at least one group received neural mobilisation (alone or as part of multimodal interventions). Meta-analyses were performed where possible. The RoB 2 and the Grading of Recommendations Assessment, Development and Evaluation tools were used to assess risk of bias and to rate the certainty of evidence, respectively. RESULTS: Thirty-nine trials were identified. There was a significant effect favouring neural mobilisation for pain and function in people with low back pain, but not for flexibility. For neck pain, there was a significant effect favouring neural mobilisation as part of multimodal interventions for pain, but not for function and range of motion. Regarding other musculoskeletal conditions, it was not possible to conclude whether neural mobilisation is effective in improving pain and function. There was very low confidence for all effect estimates. CONCLUSIONS: Neural mobilisation as part of multimodal interventions appears to have a positive effect on pain for patients with low back pain and neck pain and on function in people with low back pain. For the other musculoskeletal conditions, results are inconclusive.

Transcatheter Palliation With Pulmonary Artery Flow Restrictors in Neonates With Congenital Heart Disease: Feasibility, Outcomes, and Comparison With a Historical Hybrid Stage 1 Cohort.

BACKGROUND: Neonates with complex congenital heart disease and pulmonary overcirculation have been historically treated surgically. However, subcohorts may benefit from less invasive procedures. Data on transcatheter palliation are limited. METHODS: We present our experience with pulmonary flow restrictors (PFRs) for palliation of neonates with congenital heart disease, including procedural feasibility, technical details, and outcomes. We then compared our subcohort of high-risk single ventricle neonates palliated with PFRs with a similar historical cohort who underwent a hybrid Stage 1. Cox regression was used to evaluate the association between palliation strategy and 6-month mortality. RESULTS: From 2021 to 2023, 17 patients (median age, 4 days; interquartile range [IQR], 2-8; median weight, 2.5 kilograms [IQR, 2.1-3.3]) underwent a PFR procedure; 15 (88%) had single ventricle physiology; 15 (88%) were high-risk surgical candidates. All procedures were technically successful. At a median follow-up of 6.2 months (IQR, 4.0-10.8), 13 patients (76%) were successfully bridged to surgery (median time since PFR procedure, 2.6 months [IQR, 1.1-4.4]; median weight, 4.9 kilograms [IQR, 3.4-5.8]). Pulmonary arteries grew adequately for age, and devices were easily removed without complications. The all-cause mortality rate before target surgery was 24% (n=4). Compared with the historical hybrid stage 1 cohort (n=23), after adjustment for main confounding (age, weight, intact/severely restrictive atrial septum or left ventricle to coronary fistulae), the PFR procedure was associated with a significantly lower all-cause 6-month mortality risk (adjusted hazard ratio, 0.26 [95% CI, 0.08-0.82]). CONCLUSIONS: Transcatheter palliation with PFR is feasible, safe, and represents an effective strategy for bridging high-risk neonates with congenital heart disease to surgical palliation, complete repair, or transplant while allowing for clinical stabilization and somatic growth.

Implementation of digital health in rural populations with chronic musculoskeletal conditions: A scoping review protocol.

Musculoskeletal conditions are a major source of disability worldwide, and its burden have been rising in the last decades. Rural areas, in particular, are associated with higher prevalence of these conditions as well as higher levels of disability, which is likely related to other determinants that affect these communities. Although digital health has been identified as a potential solution to mitigate the impact of these determinants, it is also known that these populations may face barriers that limit the implementation of these interventions. Therefore, the aim of this scoping review is to comprehensively map the evidence regarding the implementation of digital health interventions in rural populations with chronic musculoskeletal conditions. We will include studies published from the year 2000; that report the use of digital interventions that promote prevention, treatment or monitoring of any chronic musculoskeletal condition or chronic pain from musculoskeletal origin, in patients that live in rural areas. This protocol follows the methodological framework for scoping reviews proposed by Arksey and O'Malley, as well as the Joana Briggs Institute (JBI) approach. We will conduct the search on Medline (PubMed), EMBASE, Web of Science and Scopus, as well as grey literature databases. Two independent reviewers will screen titles and abstracts followed by a full-text review to assess the eligibility of the articles. Data extracted will include the identification of the digital interventions used, barriers and enablers identified by the patients or healthcare providers, the patient-level outcomes measured, and the implementation strategies and outcomes reported. By mapping the evidence on the implementation of digital health interventions in rural communities with musculoskeletal conditions, this scoping review will enhance our understanding of their applicability in real-world settings.

Disección carotídea espontánea: Presentación de un caso clínico con revisión de la literatura / Carotid Artery Dissection. Case Report and Literature Review

Resumen Introducción: La disección carotídea consiste en el desgarro de la pared del vaso. Es una patología infrecuente, pero es la causa más común de enfermedad vascular cerebral (EVC) isquémica en personas menores de 45 años. Las manifestaciones clínicas son muy variables. Método: Utilizamos las recomendaciones CARE para el reporte de casos clínicos. Caso clínico: Hombre de 45 años previamente sano, con debilidad aguda de la extremidad torácica derecha sin causa aparente. La tomografía simple de cráneo no evidenció alteraciones. La resonancia magnética mostró una oclusión completa de la arteria carótida interna en todos sus segmentos y disminución del flujo de la arteria cerebral media izquierda. La evolución clínica fue desfavorable. Conclusión: La disección carotídea debe sospecharse en personas con EVC sin factores de riesgo cardiovascular.

Abstract Introduction: Carotid dissection consists of a tear in the vessel wall. It is a rare pathology, but it is the most common cause of ischemic cerebral vascular disease (CVD) in people under 45 years of age. The clinical manifestations are very variable. Method: We used CARE recommendations for reporting clinical cases. Clinical case: Previously, a healthy 45-year-old man with acute weakness of the right thoracic extremity without apparent cause. The simple skull tomography did not show any alterations. MRI showed complete occlusion of the internal carotid artery in all its segments and decreased flow of the left middle cerebral artery. The clinical evolution was unfavorable. Conclusion: Carotid dissection should be suspected in people with CVD without cardiovascular risk factors.

Soft Tissue Aneurysmal Bone Cyst in the Sartorius Muscle of a 13-Year-Old Boy Mimicking Myositis Ossificans: Case Report.

INTRODUCTION: A soft tissue aneurysmal bone cyst is an extremely rare tumor. The objective of the article is to present the clinical, radiological, and histopathological features of a very unusual neoplasm of soft tissues. CASE REPORT: A 13-year-old male patient presented a painful, mobile, and rapidly growing mass on the posteromedial aspect of his left knee. Imaging studies revealed a mass that arose from the medial surface of the distal sartorius muscle, with extension to the subcutaneous fat tissue. It was a well-circumscribed solid tumor with a peripheral rim calcification on plain film, computerized tomography, and ultrasound (zonal phenomenon). On magnetic resonance imaging, a heterogenous mass on T1-weighted images (WI) and T2-WI was seen, with a peripheral hypointense rim in both sequences. An outstanding edema on T2-WI extending to the soft tissue and muscles of the medial compartment of the knee was detected. The mass was resected, and the "tumoral mimickers" histopathological and molecular (next-generation sequencing) diagnoses confirmed a soft tissue aneurysmal bone cyst. A follow-up showed that the patient was free of disease 12 months after surgery. CONCLUSION: Soft tissue aneurysmal bone cyst is a rare tumor. Appropriate clinical and radiological correlation should be performed to differentiate it from other tumor mimickers.

Therapeutic strategies and clinical evolution of patients with infantile fibrosarcoma: a unique paediatric case series

Background Infantile fibrosarcoma is the most frequent soft tissue sarcoma in newborns or children under one year of age. This tumour often implies high local aggressiveness and surgical morbidity. The large majority of these patients carry the ETV6–NTRK3 oncogenic fusion. Hence, the TRK inhibitor larotrectinib emerged as an efficacious and safe alternative to chemotherapy for NTRK fusion-positive and metastatic or unresectable tumours. However, real-world evidence is still required for updating soft-tissue sarcoma practice guidelines. Objective To report our experience with the use of larotrectinib in pediatric patients. Methods Our case series shows the clinical evolution of 8 patients with infantile fibrosarcoma under different treatments. All patients enrolled in this study received informed consent for any treatment. Results Three patients received larotrectinib in first line. No surgery was needed with larotrectinib, which led to the rapid and safe remission of tumours, even in unusual anatomical locations. No significant adverse effects were observed with larotrectinib. Conclusion Our case series supports that larotrectinib may be a therapeutic option for newborn and infant patients with infantile fibrosarcoma, especially in uncommon locations (AU)