Thymectomy in Myasthenia Gravis

Predicting worsening risk in MGFA class I, II and III myasthenia gravis patients: development and validation of a predictive nomogram

BACKGROUND

Myasthenia gravis (MG), a neuromuscular junction autoimmune disorder, causes skeletal muscle weakness. MG worsening frequently occurs during the disease course, severely impairing quality of life and elevating myasthenic crisis risk. Existing predictive models remain scarce. This study developed a predictive model for MG worsening to facilitate early risk stratification and personalized care.

RESEARCH DESIGN & METHODS

Retrospective analysis included 437 the Myasthenia Gravis Foundation of America (MGFA) class I - III myasthenia gravis patients from December 2019 to September 2024. Sociodemographic, clinical variables and worsening status were analyzed. Predictors were identified via univariate analysis, the Least Absolute Shrinkage and Selection Operator (LASSO) regression, and multivariate logistic regression. Model performance was assessed using receiver operating characteristic (ROC) analysis, calibration curves, and decision curve analysis.

RESULTS

Patients were randomized into training (n = 305) and validation (n = 132) cohorts. Worsening rates were comparable (26.52% vs. 31.15%, p = 0.331). Six predictors emerged: age, MGFA classification, thymectomy history, chills, fatigue, and emotional disturbances (ED). The nomogram demonstrated strong discrimination (AUC: 0.82 training, 0.83 validation) and calibration (Hosmer-Lemeshow p > 0.05). Decision curve analysis confirmed clinical utility at 10-70% probability thresholds.

CONCLUSION

This nomogram integrates accessible clinical variables to stratify MG worsening risk, enabling early intervention. Validation through multicenter prospective studies is warranted to optimize generalizability.

Surgical approaches for thymectomy: a narrative review

Background and Objective

Thymectomy continues to be a standard treatment strategy for patients with thymic neoplasms and myasthenia gravis. The total thymectomies performed has exponentially increased by 69.8% between 2012 and 2019. Trans-sternal and minimally invasive thymectomy increased by 62.8% and 83.7%, respectively. Our objective is to provide a narrative overview of the various approaches of thymectomy. We have briefly described the indications for thymectomy, discussed important preoperative considerations and an operative description of the different techniques of the procedure. We have aimed to summarize the pros and cons of each approach and narrated the technique we have adopted at the University of Minnesota.

Methods

A literature search was conducted encompassing original full-length articles, meta-analyses, review articles and case reports up to July 2024 from the MEDLINE and Google Scholar databases.

Key Content and Findings

Complete surgical resection remains the goal to decrease the risk of recurrence for non-myasthenic thymomas and thymic carcinomas. Surgical procedures have evolved from traditional open approaches to a wide variety of minimally invasive methods. A variety of factors specific to the tumor, patient and surgeon have to be considered while planning a thymectomy.

Conclusions

As of today, there is no consensus on the best surgical technique, with each approach providing specific pros and cons. Each technique may be a viable option in the management of thymic pathologies, thus preoperative evaluation in patients is necessary to optimize prognosis and outcomes.

Burden of Myasthenia Gravis in the Czech Republic: Analysis of the Nationwide Patient Registry

INTRODUCTION

The main goal of this study was to describe the Czech population of patients with MG in terms of demographics, disease characteristics, management approaches, and treatment trends.

METHODS

We selected all patients, both incident and prevalent, who were enrolled in the Czech MyReg registry between August 24, 2015 and November 19, 2021. For the descriptive analysis, all patients enrolled in the registry, regardless of their date of diagnosis or date of enrolment, were included. We analyzed the following disease-related endpoints: myasthenia gravis composite (MGC) score, forced vital capacity (FVC), and Myasthenia Gravis Foundation of America (MGFA) clinical classification.

RESULTS

The incidence showed a consistent increasing trend from 0.62 to 3.13. The mean MGC score was 5.0 (median 4.0, 95% CI 4.7, 5.3) representing mild form of MG. The difference in FVC from the predicted value in patients during and without myasthenic crisis was 58.93% (95% CI 37.27, 80.59) and 75.93% (95% CI 74.87, 77.00), respectively. We identified 70 patients (5.0%) with refractory MG, of whom 58.6% were female. The MGFA classifications in those with refractory vs. non-refractory disease was as follows: IIa 21.8% vs 23.2%, IIb 45.3% vs 33.6%, and IIIb 14.1% vs 4.6%, respectively.

CONCLUSION

Our analysis shows that the incidence of MG is increasing in the Czech Republic and that patients with refractory disease, of whom up to 58% are female, have a higher burden of disease than non-refractory patients.

Management of Advanced Thymoma Presenting with Myasthenia Gravis in a Resource-limited Setting: A Case Report

Thymomas are rare tumours which generally account for only 0.2 - 1.5% of mediastinal tumours in adults. Around 40% of patients present with systemic symptoms such as motor weakness due to myasthenia gravis (MG), pure red cell aplasia, and hypogammaglobulinemia. Based on recent guidelines, management of advanced thymoma uses a multimodal approach, which is thymectomy followed by radiotherapy, but not all health care centers have radiotherapy facilities. A 52-year-old woman presented with nasal voice and had difficulty swallowing food. Patient was diagnosed with myasthenia gravis (MG). CT scan with contrast of the thorax showed a heterogenous solid mass in anterior mediastinum. Histopathological examination showed thymoma type B2. Thymectomy followed by seven cycles of platinum-based chemotherapy were done on the patient. Evaluation afterward showed complete remission of thymoma. The patient's motor weakness improved after the chemotherapy. Post-chemotherapy period was uneventful at six months on follow-up visit. The dosage of acetylcholinesterase inhibitor drug is reduced periodically due to improvement in motor weakness. The case emphasizes how to manage an advanced thymoma with MG with limited therapeutic options, and the importance of multidisciplinary management involving oncologists, surgeons, and neurologists.

[Robotic and thoracoscopic surgeries for anterior mediastinal neoplasms]

OBJECTIVE

To evaluate the efficacy and safety of robot-assisted (RATS) and video-assisted thoracoscopic (VTS) minimally invasive surgeries for anterior mediastinal neoplasms.

MATERIAL AND METHODS

The study involved 74 patients who underwent surgeries for anterior mediastinal neoplasms between 2020 and 2023. Patients were divided into two groups: group 1 (RATS, 33 patients) and group 2 (VTS, 41 patients). The following parameters were evaluated: surgery time, incidence of postoperative complications, pain syndrome and recovery time.

RESULTS

Duration of RATS was significantly shorter (mean 120 min) compared to VTS (140 min) (p< 0.05). Postoperative pain was also lower in the RATS group (4.5 vs. 6.0 points) (p< 0.05). The incidence of complications was lower in the same group that contributed to earlier recovery.

CONCLUSION

Robot-assisted surgeries are preferable for anterior mediastinal tumors. The advantages of RATS include shorter surgery time, lower pain and complication rate. Thus, this approach is more advisable in high-risk patients.

Autoantibodies in neuromuscular disorders: a review of their utility in clinical practice

A great proportion of neuromuscular diseases are immune-mediated, included myasthenia gravis, Lambert-Eaton myasthenic syndrome, acute- and chronic-onset autoimmune neuropathies (anti-MAG neuropathy, multifocal motor neuropathy, Guillain-Barré syndromes, chronic inflammatory demyelinating polyradiculoneuropathy, CANDA and autoimmune nodopathies), autoimmune neuronopathies, peripheral nerve hyperexcitability syndromes and idiopathic inflammatory myopathies. The detection of autoantibodies against neuromuscular structures has many diagnostic and therapeutic implications and, over time, allowed a better understanding of the physiopathology of those disorders. In this paper, we will review the main autoantibodies described in neuromuscular diseases and focus on their use in clinical practice.

Trends and Disparities in the Utilization of Thymectomy for Myasthenia Gravis in the United States

Background and Objectives

In 2016, a randomized controlled trial demonstrated the clinical efficacy of trans-sternal thymectomy for patients with non-thymomatous myasthenia gravis (MG). Whether large-scale changes occurred in clinical practice after this trial is unknown.

Methods

We performed a retrospective longitudinal cross-sectional analysis using National Inpatient Sample (NIS) data from 2012 to 2019. Our study included hospitalized adults at least 18 years of age diagnosed with MG without an associated thymoma. We used joinpoint regression to analyze annual trends in thymectomy volume and surgical approach (minimally invasive vs trans-sternal) from 2012 to 2019. Using logistic regression models, we examined patient and hospital-level factors that may have influenced whether thymectomy was performed, such as age, sex, race, insurance payor, hospital size and teaching status, and Elixhauser Comorbidity Index. Sampling weights were applied to account for the complex survey design of NIS.

Results

The total number of thymectomy procedures increased by 69.8% per year (95% CI 40.1-105.8) between 2012 and 2019. Trans-sternal thymectomies increased by 62.8% per year (95% CI 35.8-95.2) and minimally invasive thymectomies by 83.7% per year (95% CI 38.1-144.3). Thymectomies were significantly more likely to occur in 2017-2019 compared with 2012-2016 (OR 1.93, 95% CI 1.62-2.31). In a multivariable regression model, several factors decreased the odds of patients with MG having a thymectomy: older age, Black race (OR 0.62, 95% CI 0.49-0.77), female (OR 0.73, 95% CI 0.63-0.86), and higher Elixhauser Comorbidity Index. Patients in medium (OR 1.82, 95% CI 1.30-2.55) or large (OR 2.81, 95% CI 2.07-3.82) size and urban teaching hospitals (OR 6.09, 95% CI 2.65-13.97) were more likely to undergo thymectomy.

Discussion

Thymectomy is being performed more frequently for non-thymomatous MG, especially after 2016 after publication of a positive phase III clinical trial. There are several disparities in thymectomy utilization that warrant further attention.

Descriptive analysis of therapeutic outcomes between thoracoscopic and transsternal thymectomy in myasthenia gravis patients from 2011 to 2021

BACKGROUND

Myasthenia gravis is an autoimmune disease with high prevalence of thymus disorders, in which, thymectomy is considered one of the therapeutic approaches in improving the patients' clinical outcomes. Today, thoracoscopic thymectomy has received significant attention than the classic transsternal approach due to fewer complication. Therefore, this study was designed with the aim of investigating the therapeutic outcomes of thymectomy in patients with myasthenia gravis in the Afzalipour Hospital of Kerman between 2011 and 2021.

METHODS

The current study is a descriptive analytical study on patients with myasthenia gravis who underwent surgical thymectomy within 2011-2021. Demographic and clinical characteristics of patients from the time of operation to three years of follow-up were extracted and recorded from clinical records or by phone calls. Data were analyzed using SPSS software.

RESULTS

The data of 70 patients who underwent surgical thymectomy were analyzed. Thymectomy caused a significant reduction in the severity of the disease according to the Osserman classification (P = 0.001). It also significantly reduced the use of corticosteroids (P = 0.001) and IVIG (P = 0.015) compared to the time before the surgery. Sixty-two patients (88.57%) needed to take less medicine than before surgery. Left VATS was associated with less post-operative severity of the disease (P = 0.023). There were only two deaths during the follow-up period.

CONCLUSION

Overall, the findings of the present study demonstrated that thoracoscopic thymectomy is a useful surgical approach that leads to faster recovery, reducing the severity of the disease, need for medication, and complications in patients with myasthenia gravis, In comparison with the transsternal approach.

National Multicenter Study on the Comparison of Robotic and Open Thymectomy for Thymic Neoplasms in Myasthenic Patients: Surgical, Neurological and Oncological Outcomes

Thymectomy is the gold standard in the treatment of thymic neoplasm and plays a key role in the therapeutic path of myasthenia gravis. For years, sternotomy has been the traditional approach for removing anterior mediastinal lesions, although the robotic thymectomy is now widely performed. The literature is still lacking in papers comparing the two approaches and evaluating long-term oncological and neurological outcomes. This study aims to analyze the postoperative results of open and robotic thymectomy for thymic neoplasms in myasthenic patients. Surgical, oncological and neurological data of myasthenic patients affected by thymic neoplasms and surgically treated with extended thymectomy, both with the open and the robotic approach, in six Italian Thoracic Centers between 2011 and 2021 were evaluated. A total of 213 patients were enrolled in the study: 110 (51.6%) were treated with the open approach, and 103 (48.4%) were treated with robotic surgery. The open surgery, compared with the robotic, presented a shorter operating time (p < 0.001), a higher number of postoperative complications (p = 0.038) and longer postoperative hospitalization (p = 0.006). No other differences were observed in terms of surgical, oncological or neurological outcomes. The robotic approach can be considered safe and feasible, comparable to the open technique, in terms of surgical, oncological and neurological outcomes.

Myasthenia Gravis: Novel Findings and Perspectives on Traditional to Regenerative Therapeutic Interventions

The prevalence of myasthenia gravis (MG), an autoimmune disorder, is increasing among all subsets of the population leading to an elevated economic and social burden. The pathogenesis of MG is characterized by the synthesis of autoantibodies against the acetylcholine receptor (AChR), low-density lipoprotein receptor-related protein 4 (LRP4), or muscle-specific kinase at the neuromuscular junction, thereby leading to muscular weakness and fatigue. Based on clinical and laboratory examinations, the research is focused on distinguishing MG from other autoimmune, genetic diseases of neuromuscular transmission. Technological advancements in machine learning, a subset of artificial intelligence (AI) have been assistive in accurate diagnosis and management. Besides, addressing the clinical needs of MG patients is critical to improving quality of life (QoL) and satisfaction. Lifestyle changes including physical exercise and traditional Chinese medicine/herbs have also been shown to exert an ameliorative impact on MG progression. To achieve enhanced therapeutic efficacy, cholinesterase inhibitors, immunosuppressive drugs, and steroids in addition to plasma exchange therapy are widely recommended. Under surgical intervention, thymectomy is the only feasible alternative to removing thymoma to overcome thymoma-associated MG. Although these conventional and current therapeutic approaches are effective, the associated adverse events and surgical complexity limit their wide application. Moreover, Restivo et al. also, to increase survival and QoL, further recent developments revealed that antibody, gene, and regenerative therapies (such as stem cells and exosomes) are currently being investigated as a safer and more efficacious alternative. Considering these above-mentioned points, we have comprehensively reviewed the recent advances in pathological etiologies of MG including COVID-19, and its therapeutic management.

Novel treatment strategies for acetylcholine receptor antibody-positive myasthenia gravis and related disorders

The presence of autoantibodies directed against the muscle nicotinic acetylcholine receptor (AChR) is the most common cause of myasthenia gravis (MG). These antibodies damage the postsynaptic membrane of the neuromuscular junction and cause muscle weakness by depleting AChRs and thus impairing synaptic transmission. As one of the best-characterized antibody-mediated autoimmune diseases, AChR-MG has often served as a reference model for other autoimmune disorders. Classical pharmacological treatments, including broad-spectrum immunosuppressive drugs, are effective in many patients. However, complete remission cannot be achieved in all patients, and 10% of patients do not respond to currently used therapies. This may be attributed to production of autoantibodies by long-lived plasma cells which are resistant to conventional immunosuppressive drugs. Hence, novel therapies specifically targeting plasma cells might be a suitable therapeutic approach for selected patients. Additionally, in order to reduce side effects of broad-spectrum immunosuppression, targeted immunotherapies and symptomatic treatments will be required. This review presents established therapies as well as novel therapeutic approaches for MG and related conditions, with a focus on AChR-MG.

Systemic lupus erythematosus after delivery and myasthenia gravis with COL6A1 gene mutation: A case report

The coexistence of systemic lupus erythematosus (SLE) and myasthenia gravis (MG) is rarely reported, especially the appearance of SLE before MG. In addition to the production of autoantibodies after thymectomy, gene mutation may be an important contributing factor to the overlap of SLE and MG. Here, we report a case of a female patient diagnosed with SLE before MG and found to carry the heterozygous variation COL6A1 c. 2608G>A. We propose that this gene variation weakens the function of COL6A1 and indirectly activates STAT1, resulting in the phenotype of these two autoimmune diseases. This report suggests that it is feasible to explore common pathogenic genes in SLE and MG through future large-scale research.

The Lived Experience of Myasthenia Gravis: A Patient-Led Analysis

Introduction

A greater understanding of the reality of living with myasthenia gravis (MG) may improve management and outcomes for patients. However, there is little published data on the patient perspective of how MG impacts life. Our objective was to reveal the lived experience of MG from the patient perspective.

Methods

This analysis was led by an international Patient Council comprising nine individuals living with MG who serve as local/national patient advocates in seven countries (Europe and the United States). Insights into the lived experience of MG were consolidated from three sources (a qualitative research study of 54 people with MG or their carers from seven countries; a previous Patient Council meeting [September 2019]; and a literature review). Insights were prioritised by the Patient Council, discussed during a virtual workshop (August 2020) and articulated in a series of statements organised into domains. Overarching themes that describe the lived experience of MG were identified by the patient authors.

Results

From 114 patient insights and supporting quotes, the Patient Council defined 44 summary statements organised into nine domains. Five overarching themes were identified that describe the lived experience of MG. These themes include living with fluctuating and unpredictable symptoms; a constant state of adaptation, continual assessment and trade-offs in all aspects of life; treatment inertia, often resulting in under-treatment; a sense of disconnect with healthcare professionals; and feelings of anxiety, frustration, guilt, anger, loneliness and depression.

Conclusion

This patient-driven analysis enriches our understanding of the reality of living with MG from the patient perspective.

Novel Combination of Surface Markers for the Reliable and Comprehensive Identification of Human Thymic Epithelial Cells by Flow Cytometry: Quantitation and Transcriptional Characterization of Thymic Stroma in a Pediatric Cohort

Thymic epithelial cells (TECs) are essential in supporting the development of mature T cells from hematopoietic progenitor cells and facilitate their lineage-commitment, proliferation, T-cell receptor repertoire selection and maturation. While animal model systems have greatly aided in elucidating the contribution of stromal cells to these intricate processes, human tissue has been more difficult to study, partly due to a lack of suitable surface markers comprehensively defining human TECs. Here, we conducted a flow cytometry based surface marker screen to reliably identify and quantify human TECs and delineate medullary from cortical subsets. These findings were validated by transcriptomic and histologic means. The combination of EpCAM, podoplanin (pdpn), CD49f and CD200 comprehensively identified human TECs and not only allowed their reliable distinction in medullary and cortical subsets but also their detailed quantitation. Transcriptomic profiling of each subset in comparison to fibroblasts and endothelial cells confirmed the identity of the different stromal cell subsets sorted according to the proposed strategy. Our dataset not only demonstrated transcriptional similarities between TEC and cells of mesenchymal origin but furthermore revealed a subset-specific distribution of a specific set of extracellular matrix-related genes in TECs. This indicates that TECs significantly contribute to the distinct compartmentalization - and thus function - of the human thymus. We applied the strategy to quantify TEC subsets in 31 immunologically healthy children, which revealed sex-specific differences of TEC composition early in life. As the distribution of mature CD4- or CD8-single-positive thymocytes was correspondingly altered, the composition of the thymic epithelial compartment may directly impact on the CD4-CD8-lineage choice of thymocytes. We prove that the plain, reliable strategy proposed here to comprehensively identify human TEC subpopulations by flow cytometry based on surface marker expression is suitable to determine their frequency and phenotype in health and disease and allows sorting of live cells for downstream analysis. Its use reaches from a reliable diagnostic tool for thymic biopsies to improved phenotypic characterization of thymic grafts intended for therapeutic use.

Clinical features and outcome of acquired myasthenia gravis in 94 dogs

Background

Factors known to be associated with outcome of acquired myasthenia gravis (MG) in dogs are limited.

Hypothesis/Objectives

Of dogs with MG, advancing age and comorbid neoplasia are associated with poor long‐term prognosis and low rates of remission.

Animals

Ninety‐four client‐owned dogs with MG diagnosed by acetylcholine receptor antibody (AChR Ab) assay between 2001 and 2019 from a university clinic and 3 private clinics in the United States.

Methods

Cases were retrospectively evaluated and data were collected to determine clinical signs, treatment, and response to therapy defined by means of a clinical scoring rubric. Immunological remission was defined as a return of the AChR Ab concentration to <0.6 nmol/L. Multivariable binary logistic regression analysis was used to identify clinical criteria predicting remission.

Results

An anticholinesterase drug was used to treat 90/94 (96%) dogs, which in 63/94 (67%) was the sole treatment; other drugs included immune modulators. Clinical remission (lack of clinical signs ≥4 weeks after treatment cessation) was observed in 29 (31% [95% confidence interval (CI): 22.4‐40.8%]) dogs, clinical response (lack of clinical signs on treatment) in 14 (15% [95% CI: 9.0‐23.6%]) dogs, clinical improvement (on treatment) in 24 (26% [95% CI: 17.8‐35.2%]) dogs, and no clinical improvement in 27 (29% [95% CI: 20.5‐38.6%]) dogs. Immunological remission was observed in 27/46 (59%) dogs, with clinical remission in all 27. Younger age (P = .04) and comorbid endocrine disease (P = .04) were associated with clinical remission. Initial AChR Ab concentration (P = .02) and regurgitation (P = .04) were negatively associated with clinical remission.

Conclusions and Clinical Importance

Clinical remission in MG is less likely in older dogs and dogs presenting with regurgitation or high initial AChR Ab concentration, but more likely in younger dogs and dogs with comorbid endocrine disease.

Myasthenia gravis presenting as bilateral pseudointernuclear ophthalmoplegia in a patient with an incidental prolactinoma

Myasthenia gravis (MG) is a rare and potentially dangerous autoimmune condition, which affects the acetylcholine receptors at the neuromuscular junction of skeletal muscle. MG's diverse symptomatology may readily masquerade as other neurological conditions, posing a diagnostic challenge to clinicians. We describe a 24-year old man who presented to the emergency department with a new onset internuclear ophthalmoplegia. After a series of investigations, we eventually arrived at a diagnosis of MG with pseudointernuclear ophthalmoplegia with an incidentally detected prolactinoma. We explore the literature regarding the pathophysiology of pseudointernuclear ophthalmoplegia, the link between prolactin and autoimmunity and the association between prolactinoma and MG.

[Clinical course of myasthenia gravis at the department of neurology in Antananarivo Madagascar]

Introduction

myasthenia gravis (MG) is a rare disease affecting the neuromuscular junction. It can lead to a life-threatening condition, especially when it is associated with respiratory failure. Full remission is possible with treatment. Our aims are to describe the clinical course of patients with MG with under treatment, in order to further improve management and to implement a database of patients living in Madagascar.

Methods

we conducted a descriptive retrospective study in the Department of Neurology at the Befelatanana Antananarivo University Hospital Center between January 2010 and December 2017. This study involved all patients diagnosed with MG based on positive prostigmin test.

Results

among the 5814 hospitalized patients, 25 (0,42%) were included. Only 16 patients were on follow-up (64%) of whom 14 were receiving medical treatment. Three of them had undergone thymectomy. The mean follow-up period was 24 months. Among treated patients, 8 improved and 2 died. Among thymectomized patients, 2 improved and 1 died.

Conclusion

myasthenia gravis is a rare but serious disease. Improvement is possible with treatment even in the absence of adequate technical equipment for its management in Madagascar. Currently, a campaign in partnership with Myasthenia Gravis Association in Madagascar is underway for breathing devices useful especially when myasthenic crises occur.

Autoimmune disorders and paraneoplastic syndromes in thymoma

Thymomas are counted among the rare tumour entities which are associated with autoimmune disorders (AIDs) and paraneoplastic syndromes (PNS) far more often than other malignancies. Through its complex immunological function in the context of the selection and maturation of T cells, the thymus is at the same time highly susceptible to disruptive factors caused by the development and growth of thymic tumours. These T cells, which are thought to develop to competent immune cells in the thymus, can instead adopt autoreactive behaviour due to the uncontrolled interplay of thymomas and become the trigger for AID or PNS affecting numerous organs and tissues within the human body. While myasthenia gravis is the most prevalent PNS in thymoma, numerous others have been described, be they related to neurological, cardiovascular, gastrointestinal, haematological, dermatological, endocrine or systemic disorders. This review article sheds light on the pathophysiology, epidemiology, specific clinical features and therapeutic options of the various forms as well as courses and outcomes of AID/PNS in association with thymomas. Whenever suitable and backed by the limited available evidence, the perspectives from both the thymoma and the affected organ/tissue will be highlighted. Specific issues addressed are the prognostic significance of thymectomy on myasthenia gravis and other thymoma-associated AID/PND and further the impact and safety of immunotherapies on AID and PND relating to thymomas.

Effectiveness and safety of thymectomy plus prednisone compares with prednisone monotherapy for the treatment of non-thymomatous Myasthenia Gravis: Protocol for a systematic review

BACKGROUND

The pathogenesis of myasthenia gravis (MG) has strong connection with thymic abnormalities. Thymic hyperplasia or thymoma can be found with most patients. Thymectomy is currently one of the regular treatment in clinic, which is, however, still controversial for non-thymomatous MG. This research will assess the effectiveness and safety of thymectomy plus prednisone compared to prednisone monotherapy for the treatment of non-thymomatous MG systematically.

METHODS

According to eligibility and ineligibility criteria, 8 databases, including PubMed, EMBASE, the Web of Science, the Cochrane Library, China National Knowledge Infrastructure (CNKI), Wan-fang Database, Chinese Biomedical Literature Database (CBM), China Science and Technology Journal Database (CSTJ), will be searched to gather the up-to-standard articles from September 2000 to September 2025. Inclusion criteria are as follows: randomized controlled trials of thymectomy plus prednisone for the treatment of non-thymomatous MG. The quantitative myasthenia gravis score (QMG) and the dose of prednisone required will be accepted as the main outcomes. Data synthesis, subgroup analysis, sensitivity analysis, and meta-regression analysis will be conducted using RevMan 5.3 software. We will use Egger or Begg test to evaluate symmetry on a funnel plot which is made to assess reporting bias, and use trial sequential analysis (TSA) to exclude the probability of false positives.

RESULTS

This systematic review will measure the QMG and the dose of prednisone required, the myasthenia gravis activities of daily living scale scores (MG-ADL), treatment-associated complications, incidence of myasthenic crisis and other aspects to comprehensively assess the clinical benefits of thymectomy plus prednisone for MG patients without thymoma.

CONCLUSION

The conclusion of this study will achieve convincing evidence to evaluate the effectiveness and safety of thymectomy plus prednisone for the treatment of non-thymomatous MG.

PROSPERO REGISTRATION NUMBER

CRD 42020167735.

Update on immune-mediated therapies for myasthenia gravis

With the exception of thymectomy, immune modulatory treatment strategies and clinical trials in myasthenia gravis over the past 50 y were mainly borrowed from experience in other nonneurologic autoimmune disorders. The current experimental therapy paradigm has significantly changed such that treatments directed against the pathological mechanisms specific to myasthenia gravis are being tested, in some cases as the initial disease indication. Key advances have been made in three areas: (i) the expanded role and long-term benefits of thymectomy, (ii) complement inhibition to prevent antibody-mediated postsynaptic membrane damage, and (iii) neonatal Fc receptor (FcRn) inhibition as in vivo apheresis, removing pathogenic antibodies. Herein, we discuss these advances and the potential for these newer therapies to significantly influence the current treatment paradigms. While these therapies provide exciting new options with rapid efficacy, there are anticipated challenges to their use, especially in terms of a dramatic increase in cost of care for some patients with myasthenia gravis.

A case of thymoma in myasthenia gravis: Successful outcome after thymectomy

INTRODUCTION

Thymic abnormalities occur as hyperplasia and thymoma. Myasthenia gravis is commonly present in thymoma. Thymectomy possesses risk due to anatomical proximity with vital thoracic structures and myasthenia crisis.

PRESENTATION OF CASE

Forty five years female with complaints of difficulty swallowing and weakness of upper limb muscles upon investigation showed mass in mediastinum and antibody test for myasthenia gravis positive. Medical management was done for a month followed by thymectomy. There were no intra and postoperative complications. Medical management was stopped one month after surgery and she is symptom free.

DISCUSSION

Thymectomy is the standard of care where median sternotomy is the mainstay approach to surgery. Various other surgical approaches and complications revolving around surgery has been discussed.

CONCLUSION

Surgical removal of thymoma cured myasthenia gravis in our case. We focused on proper preoperative optimization of myasthenia gravis symptoms before thymectomy.

Mucosa-associated lymphoid tissue lymphoma of the accessory parotid gland presenting as a simple cheek mass: A case report

RATIONALE

Mucosa-associated lymphoid tissue (MALT) lymphoma, also known as extranodal marginal zone B-cell lymphoma, usually occurs in the gastric mucosa, lung, lacrimal glands, and salivary glands. MALT lymphoma arising from the accessory parotid gland is extremely rare and can therefore be easily confused with other types of soft tissue masses.

PATIENT CONCERNS

A 56-year-old woman presented with a 1-month history of a mass on the left cheek. The mass was hard and nontender. She had a history of thymectomy 26 years ago due to myasthenia gravis.

DIAGNOSIS

A soft tissue tumor measuring 2.5 × 0.8 cm was identified in the left accessory parotid gland on ultrasonography and enhanced computed tomography (CT). Additionally, CT revealed enlargement of both lacrimal glands and an enhancing mass in the right retropharyngeal space. Under suspicion of a malignant soft tissue tumor, ultrasonography-guided fine needle aspiration biopsy was performed, with findings suggestive of marginal zone B-cell lymphoma of the accessory parotid gland.

INTERVENTIONS

The patient was transferred to the department of hematology for immunochemotherapy.

OUTCOMES

The patient has received 6 cycles of rituximab with cyclophosphamide, vincristine, and prednisone chemotherapy. After 6-month follow-up, enhanced CT demonstrated complete remission. Now she is currently under periodic follow-up.

LESSONS

Physicians and surgeons should be aware that MALT lymphoma can occur in the accessory parotid gland. When this is suspected, careful history-taking, imaging workup, and biopsy are essential for accurate diagnosis and treatment.

Unexpected dislocation following accurate total hip arthroplasty caused by excessive hip joint laxity during myasthenic crisis: a case report

BACKGROUND

Dislocation following total hip arthroplasty is mainly caused by malposition. However, the coexistence of neuromuscular disorders is also considered a risk for dislocation due to excessive hip joint laxity. To minimize risk of dislocation, preoperative planning using combined anteversion has been widely used. The recommended combined anteversion angle (the total of cup and stem anteversion angles) is 50 ± 10°.

CASE PRESENTATION

A 33-year-old Japanese woman underwent elective total hip arthroplasty due to osteonecrosis of the femoral head associated with corticosteroid pulse therapy for myasthenia gravis. Intraoperatively, no tendency of dislocation was found when simulating an evoking position under general anesthesia. In postoperative X-ray and computed tomography scans, cup inclination, cup anteversion, and stem anteversion angles were 37°, 13°, and 35° respectively. The resulting combined anteversion was 48°, which was set as the target along with accurate placement. Her postoperative course was normal and she was discharged without adverse events. Three months postoperatively, due to worsening of myasthenic weakness in her lower extremities while resting, she tended to raise her left limb up using both hands for sitting up. An anterior dislocation occurred when her legs were in a figure-of-four position. She was brought to an emergency department, and reduction of dislocation was performed. It was inferred that myasthenic crisis in the affected limb enabled excessive passive motion due to joint hyperlaxity. At the end of 2016, elective total hip arthroplasty on the contralateral side was performed. Cup anteversion, stem anteversion, and the combined anteversion angles were 27°, 24°, and 51° respectively. We instructed her to exercise care during passive leg movement, which may worsen her myasthenic condition. She returned to a normal life and was able to walk long distances without a cane. No recurrence of dislocation was seen at final follow-up.

CONCLUSIONS

Even if accurate component orientation is attained in total hip arthroplasty, patients with neuromuscular disorders such as myasthenia gravis have a potential risk of muscle weakness in the affected limb. Therefore, physicians' instructions and patients' careful attention are required to prevent dislocation due to excessive hip joint laxity under conditions of motor weakness.

Clinical outcome of thymectomy in myasthenia gravis patients: A report from Iran

Background: Myasthenia gravis (MG) is an autoimmune disease affecting acetylcholine postsynaptic receptor of voluntary muscles. Thymectomy is done in these patients and is a mainstay in the treatment of MG; however, the long-term result of surgery is still controversial. This study dealt with the investigation of the results of thymectomy in treatment, recovery and control of the symptoms of these patients. Methods: This study was performed through a retrospective method in patients suffering from MG who underwent trans-sternal thymectomy between 2011 and 2016. We conducted thymectomy, excision of mediastinal mass and contents of tissues between the right and left phrenic nerves for all patients. Then, the effect of various variables including age, sex, time interval between onset of disease and surgery, thymus pathology and the dosage of drug on clinical response after surgery was determined using various statistical tests. Results: 47 patients including 26 men and 21 women with the mean age of 33.0 ± 4.6 years have been investigated. The mean age of patients was 36.2 and 29.7 in men and women respectively (P = 0.041). Spiral chest computed tomography (CT) scan was present in 47 patients demonstrating mediastinal mass in 40 (85.1%) patients. Also, our pathological results showed thymic cells in aortopulmonary window contents of 4 patients. According to the results, the younger age of patients at the time of surgery, shorter time between diagnosis and thymectomy, being a woman and non-thymoma pathology were along with better clinical outcomes after thymectomy. Conclusion: Our study shows better clinical results of thymectomy in patients with normal chest CT scan and normal or atrophic thymus in pathologic reports. Generally, it seems that performing thymectomy in a shorter time interval after diagnosis of MG is beneficial. Moreover, in MG patients who do not suffer from thymoma, it is along with positive results.