Long-term outcome and quality of life after open and thoracoscopic thymectomy for myasthenia gravis: analysis of 131 patients

Systematic review of the patient burden of generalised myasthenia gravis in Europe, the Middle East, and Africa

BACKGROUND

Myasthenia gravis (MG) is a rare autoimmune disease characterised by muscle weakness, and progression from ocular (oMG) to generalised (gMG) symptoms results in a substantial negative impact on quality of life (QoL). This systematic review aimed to provide an overview of the patient burden experienced by people living with gMG.

METHODS

Electronic database searches (conducted March 2022), supplemented by interrogation of grey literature, were conducted to identify studies reporting patient burden outcomes in patients with gMG in Europe, the Middle East and Africa. Results were synthesised narratively due to the heterogeneity across trials.

RESULTS

In total, 39 patient burden publications (representing 38 unique studies) were identified as relevant for inclusion in the systematic review, consisting of 37 publications reporting formal patient-reported outcome measures (PROMs), and two publications describing alternative qualitative assessments of patient experience. The studies included a variety of measures including generic and disease-specific PROMs, as well as symptom-specific PROMs focusing on key comorbidities including depression, anxiety, fatigue and sleep disturbance. The findings showed some variation across studies and PROMs; however, in general there was evidence for worse QoL in patients with gMG than in healthy controls or in patients with oMG, and a trend for worsening QoL with increasing MG severity.

CONCLUSIONS

This review highlights the importance of considering patient QoL when developing and assessing treatment and management plans for patients with gMG. However, the heterogeneity identified across studies illustrates the need for further representative and well-powered studies in large cohorts administering consistent, validated questionnaires.

TRIAL REGISTRATION

The protocol for this systematic review was registered in PROSPERO: CRD42022328444.

Are the minimally invasive techniques the new gold standard in thymus surgery for myasthenia gravis? Experience of a reference single-site in VATS thymectomy

The thymus is the primary lymphoid organ responsible for the maturation and proliferation of T lymphocytes. During the first years of our lives, the activation and inactivation of T lymphocytes occur within the thymus, facilitating the correct maturation of central immunity. Alterations in the positive and negative selection of T lymphocytes have been studied as the possible origins of autoimmune diseases, with Myasthenia Gravis (MG) being the most representative example. Structural alterations in the thymus appear to be involved in the initial autoimmune response observed in MG, leading to the consideration of thymectomy as part of the treatment for the disease. However, the role of thymectomy in MG has been a subject of controversy for many years. Several publications raised doubts about the lack of evidence justifying thymectomy's role in MG until 2016 when a randomized study comparing thymectomy via sternotomy plus prednisone versus prednisone alone was published in the New England Journal of Medicine (NEJM). The results clearly favored the group of patients who underwent surgery, showing improvements in symptoms, reduced corticosteroid requirements, and fewer recurrences over 3 years of follow-up. In recent years, the emergence of less invasive surgical techniques has made video-assisted or robotic-assisted thoracoscopic (VATS/RATS) thymectomy more common, replacing the traditional sternotomy approach. Despite the increasing use of VATS, it has not been validated as a technique with lower morbidity compared to sternotomy in the treatment of MG. The results of the 2016 trial highlighted the benefits of thymectomy, but all the patients underwent surgery via sternotomy. Our hypothesis is that VATS thymectomy is a technique with lower morbidity, reduced postoperative pain, and shorter postoperative hospital stays than sternotomy. Additionally, VATS offers better clinical improvement in patients with MG. The primary objective of this study is to validate the VATS technique as the preferred approach for thymectomy. Furthermore, we aim to analyze the impact of VATS thymectomy on symptoms and corticosteroid dosage in patients with MG, identifying factors that may predict a better response to surgery.

Analysis of influencing factors of postoperative myasthenic crisis in 564 patients with myasthenia gravis in a single center

OBJECTIVE

To study the influencing factors of myasthenic crisis in patients with myasthenia gravis during perioperative period.

METHODS

A total of 564 myasthenia gravis (MG) patients who underwent standard expanded resection of thymoma/thymoma in the Department of Thoracic Surgery of Beijing Hospital from January 2011 to March 2022 were retrospectively included in the study. Clinical indicators such as gender, age, thymoma, American Society of Anesthesiologists (ASA) score, operation time, intraoperative blood loss, and some others were recorded.

RESULTS

Osserman-stages IIB + III + IV (odds ratio [OR] 16.091, 95% confidence interval [CI] 5.170-50.076, p value < 0.001), the dosage of pyridostigmine bromide more than 240 mg (OR 6.462, 95% CI 3.110-13.427, p value < 0.001), ASA score 2 and 3 (OR 3.203, 95% CI 1.461-7.020, p value = 0.004), low diffusion lung capacity for carbon monoxide (DLCO%) (OR 0.981, 95% CI 0.963-1.000 p value = 0.049), and blood loss greater than 1000 ml (OR 16.590, 95% CI 1.911-144.011, p value = 0.011) were independent risk factors for myasthenic crisis.

CONCLUSIONS

Patients with poor Osserman stages, higher preoperative dosage of pyridostigmine bromide, higher ASA score, poor pulmonary function (low DLCO%), and more intraoperative bleeding should be highly vigilant for the occurrence of postoperative myasthenic crisis.

The short and long-term effects of open vs minimally invasive thymectomy in myasthenia gravis patients: a systematic review and meta-analysis

OBJECTIVE

Thymectomy has been utilized as a treatment for Myasthenia Gravis (MG) for many decades, with both open and minimally invasive surgical (MIS) techniques currently used. Although MIS has shown improved short-term results, long-term effects remain uncertain. This systematic review and meta-analysis aim to compare the post-operative and long-term outcomes of MIS versus open thymectomy in MG patients.

METHODS

MEDLINE, EMBASE and CENTRAL databases were searched from inception till January 2022 for keywords related to MG and open or MIS thymectomy. Primary outcome was complete stable remission (CSR), and secondary outcomes were clinical improvement, complications, length of stay, operation time, and blood loss. Grading of recommendations, assessment, development, and evaluation was used to assess the certainty of evidence.

RESULTS

26 studies with 3588 patients were included in the analysis. At 1, 3 and 5 years, there was no statistical difference noted in CSR between open versus MIS thymectomy. However, CSR was improved at 1 year for MIS thymectomy in non-thymomatous MG (P = 0.03). There was no significant difference in rates of partial clinical improvement between techniques at 1-year. Although analyses on length of hospital stay and blood loss showed improvement following MIS thymectomy, operative time was shorter for open thymectomy.

CONCLUSION

This is the first systematic review and meta-analysis assessing long-term effects of MIS versus open thymectomy in MG patients. Given the lack of significant differences noted, either MIS or open thymectomy can be performed, based on surgeon preference. Further high-level, long-term research should be conducted to determine the benefit of each technique.

Assessment of length of stay and cost of minimally invasive versus open thymectomies in patients with myasthenia gravis in Florida

BACKGROUND

Thymectomy has become a standard component in treatment for myasthenia gravis. The best surgical approach is still subject to debate. Minimally invasive surgery may have a lower mortality and morbidity rate, improved cosmetic results, and equivalent efficacy at improving neurologic symptoms to open approaches. We compared the perioperative outcomes and cost between the two techniques.

METHODS

We queried Florida Inpatient Discharge Dataset for patients who underwent thymectomy and had a primary diagnosis of non-thymomatous myasthenia gravis using International Classification of Diseases (ICD)-9 and ICD-10 codes to carry out this retrospective cohort study. The dates ranged between January 1st, 2013, to December 31st, 2018. We compared outcomes of patients who underwent minimally invasive thymectomy versus those who had open thymectomy.

RESULTS

An open approach was used in 108 patients, whereas a minimally invasive approach was used in 40 patients. Minimally invasive surgery group had a shorter length of stay (3.0 vs. 6.0 days, P<0.001) and had a non-significant lower total cost ($18.4K vs. $22.1K, P=0.186). After adjusting for age and Elixhauser score, length of stay for minimally invasive group was 32% (P=0.01) lower compared to the open surgery group.

CONCLUSIONS

Patients who underwent minimally invasive thymectomy for Myasthenia gravis had a significantly shorter length of stay and a lower, although not significant, overall cost.

[Long-term outcomes of thoracoscopic thymectomy for thymoma stage i-ii]

OBJECTIVE

To compare long-term outcomes of video-assisted thoracoscopic (VATS) and conventional open surgery in patients with early-stage (Masaoka stage I-II) thymic malignancies.

MATERIAL AND METHODS. A

Retrospective study included patients after VATS and open thymectomy for the period 2000-2019. Long-term outcomes were analyzed.

RESULTS

VATS thymectomy was performed in 53 (54.1%) patients, open thymectomy - in 45 (45.9%) cases. Median follow-up period was 66.9 months. Overall 5-year survival was 89.8% and 97% in the Open and VATS groups, respectively (p=0.076). Disease-free survival rates were 79.6% and 86.6% (p=0.279), respectively. There was no significant difference in cumulative incidence of recurrence (13.3% vs 7.5%, p=0.505). Age <50 years and tumor size >5 cm were the independent risk factors of recurrence.

CONCLUSION

VATS thymectomy is an effective approach ensuring similar long-term outcomes in patients with early stages of thymic malignancies.

Prevalence and risk factors of myasthenia gravis recurrence post-thymectomy

Objectives:

To evaluate the prevalence and the factors associated with recurrence of myasthenia gravis following thymectomy.

Methods:

Six electronic databases which reported on recurrence of myasthenia gravis following thymectomy and/or its risk factors from 1985 to 2018 were searched. Summary prevalence and risk values obtained based on the random effect models were reported.

Results:

Seventy (70) papers containing 7,287 individuals with myasthenia gravis who received thymectomy as part of their management were retrieved. The patients had a mean follow-up of 4.65 years post-thymectomy. The prevalence of myasthenia gravis recurrence post-thymectomy was 18.0% (95% CI 14.7–22.0%; 1865/7287). Evident heterogeneity was observed (I²=93.6%; p<0.001). Recurrence rate was insignificantly higher in male compared with female patients (31.3 vs. 23.8%; p=0.104). Pooled recurrence rates for thymomatous (33.3%) was higher than the rate among non-thymomatous (20.8%) myasthenia gravis patients (Q=4.19, p=0.041). Risk factors for recurrence include older age, male sex, disease severity, having thymomatous myasthenia gravis, longer duration of the myasthenia gravis before surgery, and having an ectopic thymic tissue.

Conclusion:

A fifth of individuals with myasthenia gravis experience recurrence after thymectomy. Closer monitoring should be given to at-risk patients and further studies are needed to understand interventions to address these risks.

Minimally invasive thymectomy for myasthenia gravis favours left-sided approach and low severity class

OBJECTIVES

Complete thymectomy is a key component of the optimal treatment for myasthenia gravis. Unilateral, minimally invasive approaches are increasingly utilized with debate about the optimal laterality approach. A right-sided approach has a wider field of view, while a left-sided approach accesses potentially more thymic tissue. We aimed to assess the impact of laterality on perioperative and medium-term outcomes, and to identify predictors of a 'good outcome' using standard definitions.

METHODS

We performed a multicentre review of 123 patients who underwent a minimally invasive thymectomy for myasthenia gravis between January 2000 and August 2015, with at least 1-year follow-up. The Myasthenia Gravis Foundation of America standards were followed. A 'good outcome' was defined by complete stable remission/pharmacological remission/minimal manifestations 0, and a 'poor outcome' by minimal manifestations 1-3. Univariate and multivariable logistic regression analyses were performed to assess factors associated with a 'good outcome'.

RESULTS

Ninety-two percent of thymectomies (113/123) were robotic-assisted. The left-sided approach had a shorter median operating time than a right-sided: 143 (interquartile range, IQR 110-196) vs 184 (IQR 133-228) min, P = 0.012. At a median of 44 (IQR 27-75) months, the left-sided approach achieved a 'good outcome' (46%, 31/68) more frequently than the right-sided (22%, 12/55); P = 0.011. Multivariable analysis identified a left-sided approach and Myasthenia Gravis Foundation of America class I/II to be associated with a 'good outcome'.

CONCLUSIONS

A left-sided thymectomy may be preferred over a right-sided approach in patients with myasthenia gravis given the shorter operating times and potential for superior medium-term symptomatic outcomes. A lower severity class is also associated with a 'good outcome'.

Assessment of the risks of a myasthenic crisis after thymectomy in patients with myasthenia gravis: a systematic review and meta-analysis of 25 studies

Background

Despite the burgeoning literature describing preoperative and postoperative risks of a myasthenic crisis after thymectomy (MCAT) in patients with myasthenia gravis, substantial differences exist in the risk factors identified by previous studies. We conducted a meta-analysis to assess the reported risk factors and MCAT risk.

Methods

We collected relevant studies on the risk factors for MCAT by searching the PubMed, Embase, The Cochrane Library, China Biology Medicine (CBM), WanFang Data, VIP and CNKI databases. The search period ranged from the establishment of the database to November 2019.

Results

Twenty-five of the 458 identified studies were eligible for the meta-analysis. Seven retrospective cohort studies and 18 case-control studies were included, and 14 risk factors for MCAT were extracted. Meta-analyses of the association between MCAT and risk factors related to the patient’s preoperative condition included a preoperative history of MC, preoperative bulbar symptoms, IIa + IIb + III + VI, IIb + III + VI, VI + V, dosage of pyridostigmine bromide prior to the operation, a preoperative AchR-Ab level > 100 (nm/L), preoperative pulmonary function, preoperative complications, and preoperative disease course. Meta-analyses of the association between MCAT and surgery-related risk factors included intraoperative blood loss > 1000 mL and the mode of operation. Meta-analyses of the association between MCAT and postoperative risk factors included postoperative lung infection, thymoma and the WHO classification. The operation time was not an independent risk factor for MCAT.

Conclusions

The independent risk factors for MCAT were a preoperative history of MC, preoperative bulbar symptoms, preoperative MG Osserman stage, preoperative dosage of pyridostigmine bromide, preoperative serum AchR-Ab level, lung function, major postoperative complications, disease duration before thymectomy, blood loss, thoracotomy, postoperative lung infection, thymoma, and WHO classification.

Comparison of the progression-free survival between robot-assisted thymectomy and video-assisted thymectomy for thymic epithelial tumors: a propensity score matching study

Background

Robotic system was recently introduced to assist surgeons in performing thymectomy. However, whether robot-assisted thoracoscopic thymectomy (RATT) could replace video-assisted thoracoscopic thymectomy (VATT) and be considered as a superior treatment for thymic epithelial tumors is still controversial. The aim of this study was to evaluate the progression-free survival (PFS) and short-term clinical outcomes in patients undergoing RATT or VATT by comparing the matched two groups after performing propensity score analysis.

Methods

We retrospectively reviewed the clinical data of 295 patients diagnosed with thymic epithelial tumors. There were 60 patients in RATT group and 235 in VATT group. Propensity score matching was done between two groups with variables of age, gender, tumor size, organization histologic classification, original Masaoka stages, presence of myasthenia gravis (MG) and adjuvant therapy. Sixty patients from the RATT group and 60 from the VATT group were matched, fitting the model. The PFS and short-term clinical outcomes of matched groups were compared.

Results

After matching, the surgical time in RATT groups was significant shorter than that in VATT groups (P=0.042). Loco-regional recurrence and distal metastasis were detected in 4 patients with thymoma and 1 patient with thymic carcinoma in RATT group and in 25 patients with thymoma and 3 patients with thymic carcinoma in VATT group before matching. PFS were estimated in only thymoma cases. The PFS in RATT group (n=55) intended to be longer than that in VATT group (n=58) after matching (5-year PFS rate: 81.5% and 75.4%, respectively; log-rank P=0.095).

Conclusions

RATT has the superiorities over VATT on short-term outcomes due to enabling surgeons to operate in a stable and comfortable environment. Meanwhile, RATT yielded a longer PFS compared with VATT, although the difference was not significant. Therefore, RATT could be considered as a standard approach for the treatment of thymic epithelial tumors.

Robotic assisted minimally invasive thymectomy with simultaneous bilateral thoracoscopy and contralateral phrenic nerve visualization

Background

Thoracoscopic approaches to thymectomy and anterior mediastinal mass resection has become increasingly common due to the potential for decreased blood loss and hospital length of stay. However, contralateral mediastinal and phrenic nerve visualization if often difficult from these unilateral approaches, which may affect the ability to achieve a full phrenic to phrenic dissection Herein, we present our early experience of robotic assisted minimally invasive thymectomy (RAMIT) with simultaneous bilateral thoracoscopy and contralateral phrenic nerve visualization.

Methods

This was a retrospective review of all sequential patients undergoing RAMIT with simultaneous bilateral thoracoscopy from January 2015 to May 2016. This study was approved by our Institutional Review Board (PRO15080367). Individual patient consent was waived.

Results

Twenty-six patients [median age 58 (range, 29-76) years] were included in this study. Sixteen operations were performed for anterior mediastinal mass, 7 for non-thymomatous myasthenia gravis, and 3 for concurrent myasthenia gravis and thymoma. Median blood loss and hospital stay were 25 mL (range, 3-150 mL) and 3 days (range, 2-8 days), respectively. Twenty-one (80.8%) patients experienced an uncomplicated hospital course. The highest graded complication by Clavien Dindo Classification was a grade III due to pleural effusion requiring drainage via pleural catheter. One patient experienced asymptomatic hemidiaphram palsy postoperatively. There were no 90-day postoperative deaths.

Conclusions

RAMIT with simultaneous bilateral thoracoscopy is a feasible approach that may allow for enhanced visualization and more complete thymic resection compared to existing unilateral minimally invasive operations. Comparative studies and long-term follow up are needed to adequately assess the potential benefits of RAMIT.

Video-assisted thoracoscopic surgery versus open surgery for Stage I thymic epithelial tumours: a propensity score-matched study

OBJECTIVES

Video-assisted thoracoscopic surgery (VATS) has been increasingly used in the management of thymic epithelial tumours. However, its oncological efficacy remains to be proved. The purpose of this study is to compare the oncological outcomes following thoracoscopic versus open surgery in the case-matched groups of patients with early-stage thymic tumours from the Chinese Alliance for Research in Thymomas (ChART) retrospective database.

METHODS

Between 1994 and 2012, a total of 1087 patients who underwent surgery for UICC (Union for International Cancer Control) pathological Stage I tumours from the ChART retrospective database were recruited for this study. A propensity score-matched analysis was used to compare the long-term outcomes in patients who received VATS or open surgery.

RESULTS

VATS resection was performed in 271 patients (24.9%) and open surgery in 816 patients (75.1%). Before propensity score matching, the VATS group had a smaller tumour size (P = 0.002), lower grade histology (P = 0.034), lower T stage (P < 0.001) and less adjuvant therapy (P < 0.001). Propensity score matching by gender, myasthenia gravis, tumour size, histological classification, pathological T stage, extent of thymectomy, adjuvant radiotherapy and adjuvant chemotherapy identified 110 patients in each group. After matching, there was no significant difference in patient demographics, tumour characteristics or adjuvant therapy. All matched patients had R0 resection. Overall survival, disease-free survival and cumulative incidence of recurrence were only predicted by WHO histology, but not by surgical approach, in both univariable and multivariable analyses. There was no significant difference in the overall survival (85.7% vs 93.1%, P = 0.539), disease-free survival (92.5% vs 91.9%, P = 0.773), cumulative incidence of recurrence (7.1% vs 5.8%, P = 0.522) and improvement rate of myasthenia gravis (83.3% vs 88.2%, P = 0.589) between the 2 groups.

CONCLUSIONS

This propensity score-matched study suggests that VATS and open surgeries are associated with similar oncological outcomes for Stage I thymic epithelial tumours. Minimally invasive surgery might be an acceptable surgical approach for early-stage thymic malignancies.

Understanding the burden of refractory myasthenia gravis

Myasthenia gravis (MG) is an autoantibody-mediated disease that compromises the acetylcholine receptors or associated structures of the postsynaptic membrane of the neuromuscular junction. This leads to impaired neuromuscular transmission and subsequent fluctuating fatigability and weakness of ocular, bulbar, and limb skeletal muscles. Over the past few decades, there have been significant advances in our understanding of the disease pathophysiology and improvements in prognosis due to intensive care medicine and immunomodulation. Despite this, an estimated 10-20% of patients with MG do not achieve an adequate response, are intolerant to conventional treatment, or require chronic treatment with intravenous immunoglobulins or plasma separation procedures. Such patients are regarded as having MG that is 'refractory' to treatment and may represent a distinct clinical subgroup. Because the majority of patients with MG have well-controlled disease, the burden of illness in the minority with refractory disease is poorly understood and may be underestimated. However, clinically these patients are liable to experience extreme fatigue, considerable disability owing to uncontrolled symptoms, and frequent myasthenic crises and hospitalizations. Both acute adverse effects and an increased risk of comorbidity from treatment regimens may contribute to reduced quality of life. As yet, little is known concerning the impact of refractory MG on mental health and health-related quality of life. This review aims to highlight the burden of disease and unmet needs in patients with refractory MG.

Subxiphoid and subcostal arch "Three ports" thoracoscopic extended thymectomy for myasthenia gravis

Background

The approaches to thoracoscopic thymectomy in myasthenia gravis (MG) are debatable. We developed a novel approach via subxiphoid and subcostal arch, with a significantly shorter duration of operation and hospital stay, less estimated blood loss, and lower postoperative pain.

Methods

From December 2012 to December 2014, 77 myasthenia gravis patients with or without thymoma underwent thoracoscopic extended thymectomy at our hospital. Among them, 41 patients were operated via the subxiphoid and subcostal arch approach and the other 36 via the conventional unilateral approach. The patient outcomes were retrospectively reviewed and evaluated.

Results

The thoracoscopic extended thymectomy was performed safely via the subxiphoid and subcostal arch approach. In this approach, no drainage tube was inserted after operation except in the first two patients. Two of the 41 patients were switched to trans-sternal approach due to the tight adhesion between the thymoma and the left innominate vein. No major complications occurred. Compared with the unilateral approach, the duration of the procedure via subxiphoid and subcostal arch was significantly shorter, with less estimated blood loss, shorter hospital-stay and lower postoperative pain (P<0.001). The cosmetic scores were comparable between the two groups (P=0.369).

Conclusions

The novel subxiphoid and subcostal arch approach is technically feasible and safe. It is an acceptable alternative to conventional thoracoscopic extended thymectomy.

Improved outcomes with surgery vs. medical therapy in non-thymomatous myesthenia gravis: a perspective on the results of a randomized trial

Myasthenia gravis can be a debilitating neurological disorder that affects thousands worldwide. Thymectomy has historically been considered in patients refractory to medical therapy or with concurrent thymoma. While retrospective data and propensity matched trials have favored thymectomy in order to decrease disease severity and disease associated morbidity, no randomized data existed to clearly delineate the benefit of this practice. The reviewed paper by Wolfe et al. represents the first high-level randomized prospective study investigating the role of thymectomy in patients with non-thymomatous myasthenia gravis. In a subset of antibody positive patients undergoing thymectomy within 5 years of disease onset, the study demonstrated a decrease in steroid use, hospitalization and overall disease severity compared to patients receiving best medical therapy alone. This work provides a sound evidence-based foundation to strongly consider thymectomy early in the disease process, and possibly for expanded indications. Additionally, the onus lies on surgeons to identify the most efficacious and least morbid approaches to these operations, whether they be open, minimally invasive, robotic, or otherwise.

Prognosis of thymectomy in myasthenia gravis patients with thymus hyperplasia

PURPOSE

To compare the post-thymectomy prognosis in different conditions of myasthenia gravis (MG) patients with thymus hyperplasia.

MATERIALS AND METHODS

Collecting medical record and carrying out the follow-up study of 123 myasthenia gravis patients with thymus hyperplasia who have underwent thymectomy during the period between 2003 and 2013. Dividing into different groups based on gender, age of onset, duration of disease and Myasthenia Gravis Association of America (MGFA) clinical classification to analyze different prognosis in different groups.

RESULTS

Complete stable remission (CSR) was achieved in 71 of 123 patients (59.5%). There is no gender-related difference in achieving CSR. Patients with early onset of MG (≤40 years old) or disease duration less than 12 months had significantly higher CSR rates than those with late onset of MG (>40 years old) or disease duration more than 12 months respectively, while no difference was found in remission rate between MGFA clinical classification I and MGFA II.

CONCLUSION

Myasthenia gravis patients with thymus hyperplasia who had thymectomy are proved to possess greater chance of achieving CSR. The onset age of disease and duration are the prognostic factors.

Labour market participation and sick leave among patients diagnosed with myasthenia gravis in Denmark 1997-2011: a Danish nationwide cohort study

Background

To examine labour market participation and long-term sick leave following a diagnosis with myasthenia gravis (MG) compared with the general Danish population and for specific subgroups of MG patients.

Methods

A nationwide matched cohort study from 1997 to 2011 using data from population-based medical and social registries. The study includes 330 MG patients aged 18 to 65 years old identified from hospital diagnoses and dispensed prescriptions, and twenty references from the Danish population matching each MG patient on age, gender, and profession. Main outcome measures are labour market participation (yes/no) and long-term sick leave ≥9 weeks (yes/no) with follow-up at 1- and 2 years after the time of MG diagnosis or match. Based on complete person-level information on all public transfer payments in Denmark, persons having no labour market participation are defined as individuals receiving social benefits for severely reduced workability, flexijob, and disability pension.

Results

MG is consistently associated with higher odds of having no labour market participation and long-term sick leave compared with the general Danish population (no labour market participation & ≥9 weeks sick leave at 2-year follow-up, adjusted OR (95% CI): 5.76 (4.13 to 8.04) & 8.60 (6.60 to 11.23)). Among MG patients, females and patients treated with both acetylcholinesterase inhibitors and immunosuppression have higher odds of lost labour market participation and long-term sick leave.

Conclusions

This study suggests that MG patients have almost 6 times higher odds of no labour market participation and almost 9 times higher odds of long-term sick leave 2 years after diagnosis compared with the general Danish population. In particular female MG patients and patients treated with both acetylcholinesterase and immunosuppression have high odds of a negative labour market outcome. Future research should focus on predictors in workplace and labour market policy of labour market participation among MG patients.

Sternotomy versus video-assisted thoracoscopic surgery for thymectomy of myasthenia gravis patients: A meta-analysis

INTRODUCTION

The purpose of this study was to compare thymectomy by video-assisted thoracoscopic surgery (VATS) and trans-sternal thymectomy (TS) for myasthenia gravis patients.

METHODS

A meta-analysis was conducted to compare thoracoscopic surgery and sternotomy for myasthenia gravis patients with regard to long-term effect and short-term safety.

RESULTS

A total of 23 trials were included in our research. No significant differences were detected with regard to myasthenic crisis, wound infection, and muscle weakness improvement. VATS led to less blood loss than TS (standardized mean difference, -1.233; 95% confidence interval, -1.425--1.041; P < 0.001), less risk of pulmonary infection (relative risk, 1.035; 95% confidence interval, 1.001-1.070; P = 0.043), and a shorter hospital stay. TS had a shorter operative time than VATS (standardized mean difference, 0.239; 95% confidence interval, 0.113-0.365; P < 0.001). VATS and TS achieved similar mean specimen weights and complete stable remission rates.

CONCLUSION

Based on the results of this meta-analysis of retrospective cohort studies, VATS increases surgical safety and achieves an equal surgical efficacy to TS, but TS has a shorter operative time.

Determinants of Complete Resection of Thymoma by Minimally Invasive and Open Thymectomy: Analysis of an International Registry

INTRODUCTION

Minimally invasive thymectomy (MIT) is a surgical approach to thymectomy that has more favorable short-term outcomes for myasthenia gravis than open thymectomy (OT). The oncologic outcomes of MIT performed for thymoma have not been rigorously evaluated. We analyzed determinants of complete (R0) resection among patients undergoing MIT and OT in a large international database.

METHODS

The retrospective database of the International Thymic Malignancy Interest Group was queried. Chi-square and Wilcoxon rank sum tests, multivariate logistic regression models, and propensity matching were performed.

RESULTS

A total of 2514 patients underwent thymectomy for thymoma between 1997 and 2012; 2053 of them (82%) underwent OT and 461 (18%) underwent MIT, with the use of MIT increasing significantly in recent years. The rate of R0 resection among patients undergoing OT was 86%, and among those undergoing MIT it was 94% (p < 0.0001). In propensity-matched MIT and OT groups (n = 266 in each group); however, the rate of R0 resection did not differ significantly (96% in both the MIT and OT groups, p = 0.7). Multivariate analyses were performed to identify determinants of R0 resection. Factors independently associated with R0 resection were geographical region, later time period, less advanced Masaoka stage, total thymectomy, and the absence of radiotherapy. Surgical approach, whether minimally invasive or open, was not associated with completeness of resection.

CONCLUSIONS

The use of MIT for resection of thymoma has been increasing substantially over time, and MIT can achieve rates of R0 resection for thymoma similar to those achieved with OT.

Clinical features, pathogenesis, and treatment of myasthenia gravis: a supplement to the Guidelines of the German Neurological Society

Myasthenia gravis (MG) is an autoimmune antibody-mediated disorder of neuromuscular synaptic transmission. The clinical hallmark of MG consists of fluctuating fatigability and weakness affecting ocular, bulbar and (proximal) limb skeletal muscle groups. MG may either occur as an autoimmune disease with distinct immunogenetic characteristics or as a paraneoplastic syndrome associated with tumors of the thymus. Impairment of central thymic and peripheral self-tolerance mechanisms in both cases is thought to favor an autoimmune CD4(+) T cell-mediated B cell activation and synthesis of pathogenic high-affinity autoantibodies of either the IgG1 and 3 or IgG4 subclass. These autoantibodies bind to the nicotinic acetylcholine receptor (AchR) itself, or muscle-specific tyrosine-kinase (MuSK), lipoprotein receptor-related protein 4 (LRP4) and agrin involved in clustering of AchRs within the postsynaptic membrane and structural maintenance of the neuromuscular synapse. This results in disturbance of neuromuscular transmission and thus clinical manifestation of the disease. Emphasizing evidence from clinical trials, we provide an updated overview on immunopathogenesis, and derived current and future treatment strategies for MG divided into: (a) symptomatic treatments facilitating neuromuscular transmission, (b) antibody-depleting treatments, and

Minimally invasive versus open thymectomy: a systematic review of surgical techniques, patient demographics, and perioperative outcomes

BACKGROUND

Thymectomy is the mainstay of treatment for thymoma and other anterior mediastinal tumors, and is often utilized in the management of patients with myasthenia gravis (MG). While traditionally approached through a median sternotomy, minimally invasive approaches to thymectomy have increasingly emerged. The present systematic review was conducted to compare perioperative and clinical outcomes following minimally invasive thymectomy (MIT) and open thymectomy (OT).

METHODS

Articles were obtained through a PubMed literature search. Comparative studies reporting clinical outcomes following MIT and OT were eligible for inclusion. We selected studies with full text availability, written in the English language, published after 2005 and with at least 15 patients in each arm. A descriptive analysis was performed.

RESULTS

Twenty studies were included, involving a total of 2,068 patients undergoing either MIT (n=838) or OT (n=1,230). Within individual studies, MIT and OT cohorts were well matched with regards to patient age and gender, but there was considerable variation across studies. Resected thymomas were consistently larger in OT groups, with mean diameter significantly larger in five studies (MIT, 29-52 mm; OT, 31-77 mm). MIT was consistently associated with a lower estimated blood loss (MIT, 20-200 mL; OT, 86-466 mL), chest tube duration (MIT, 1.3-4.1 days; OT, 2.4-5.3 days), and hospital length of stay (MIT, 1-10.6 days; OT, 4-14.6 days). There were no consistent differences in rates of perioperative complications, thymoma recurrence, MG complete stable remission, or 5-year survival.

CONCLUSIONS

In appropriately selected patients, MIT may reduce blood loss, chest tube duration, and hospital length of stay, with comparable clinical outcomes compared to OT via median sternotomy.

Video-assisted thoracoscopic surgery versus sternotomy in thymectomy for thymoma and myasthenia gravis

Thymectomy involves the removal of all the soft tissue in the pre-vascular plane of the anterior mediastinum between the two phrenic nerves. Surgical success in controlling myasthenia and the most important factor influencing survival in patients with thymoma depends on complete clearance of thymic tissue. Currently there is a perception that the open (median sternotomy) approach offers better visualisation of the thymic tissue. This perceived advantage is thought to justify the invasive nature of the procedure associated with increased morbidity. Video-assisted thoracoscopic surgery (VATS) for thymectomy has evolved significantly over the last decade, including bilateral and unilateral VATS (either left or right) approaches. The laterality of the approach remains largely on surgeon preferences, with the decision influenced by their experience and training. VATS offers superior illumination and magnification, particularly with the availability of advanced cameras with variable angles that provide better exposure and lighting of the operative field. The use of three-dimensional-operating imaging has also revolutionised the VATS technique. VATS thymectomy is a superior and radical technique in minimising access trauma and removing all thymic tissue that may be scattered in the anterior mediastinum and cervical fat. Other advantages of VATS include less intraoperative blood loss, early removal of chest drains, less requirement for blood products, decreased inflammatory cytokine response, shorter hospital stay and superior cosmesis. There is also a decreased risk of respiratory and cardiac related complications compared to the open (sternotomy) technique. Furthermore, no significant difference has been found in long-term complications and survival rate between VATS and open approaches. Subsequently, the VATS approach should be encouraged as more surgeons are adopting the minimally invasive practice as routine.

Minimally invasive thymectomy: the Mayo Clinic experience

BACKGROUND

The prevalence of minimally invasive thymectomy (MIT) is increasing and may have significant benefit to patients in terms of morbidity and post-operative recovery. Our aim was to review the Mayo Clinic experience of MIT.

METHODS

We reviewed data from all MIT cases collected in a prospectively maintained database from January 1995 to February 2015. Data were collected regarding patient demographics, perioperative management and patient outcomes.

RESULTS

A total of 510 thymectomies were performed in 20 years. Fifty-six patients underwent MIT (45 video-assisted thoracoscopy, 11 robotic-assisted). The median age was 55 years (range, 23-87 years) with male to female ratio of 25:31. Thymoma was the main pathologic diagnosis in 27/56 patients (48%), with 11/27 (41%) associated with myasthenia gravis (MG), and 16/27 (59%) non-MG. Other pathologies included 1/56 (2%) of each teratoma, lymphoma, lymphangioma, carcinoma and thymolipoma. There were 3/56 (5%) atrophic glands, 4/56 (7%) cysts, 6/56 (11%) benign glands and 11/56 (20%) hyperplastic. Mean blood loss (mL) and operative time (min) were significantly lower in the video-assisted thoracoscopic surgery (VATS) group compared to robotic (65±41 vs. 160±205 mL, P=0.04 and 102±39 vs. 178±53 min, P=0.001, respectively). There was no 30-day mortality. Post-operative morbidity occurred in 7/45 (16%) VATS patients (phrenic nerve palsy 7%, pericarditis 4%, atrial fibrillation 2%, pleural effusion 2%) and 1/11 (9%) robotic (urinary retention requiring self-catheterization). Reoperation was required in 1/3 of VATS patients with phrenic nerve palsy. There was no significant difference in length of hospital stay [VATS 1.5 days (range, 1-4 days) and robotic 2 days (range, 1-5 days) VATS; P=0.05]. Mean follow-up was 18.4 months (range, 1-50.4 months) with no tumor recurrences.

CONCLUSIONS

MIT can be performed with low morbidity and mortality. VATS is associated with reduced blood loss, operative times and earlier hospital discharge compared to robotic MIT.

Eight-year follow-up of patients with myasthenia gravis after thymectomy

PURPOSE

To depict the long-term outcome of patients with myasthenia gravis after thymectomy in combination with immunotherapy, and the factors that may potentially affect the outcome.

METHODS

The 306 patients with myasthenia gravis who underwent extended thymectomy from January 1984 to December 2011 at Tongji Hospital were retrospectively evaluated.

RESULTS

The patients consisted of 174 cases with thymoma and 132 cases without thymoma. Pharmaceutical treatment was tailored for each case during follow-up. Nine patients with thymomatous myasthenia gravis died during the perioperative period, and 297 patients were followed for 8.6 years. By their latest visits, 241 patients (81.1%) gained satisfactory efficacy, 24 cases died (8.1%), and 32 cases (10.8%) remained unchanged or deteriorated. Favorable factors for satisfactory efficacy included the presence of ocular myasthenia gravis before operation, no presence of thymoma, and lack of concomitant diseases. It is interesting to mention that, patients with non-thymomatous myasthenia gravis obtained significantly higher rates of complete stable remission and clinical remission than the patients with thymomatous myasthenia gravis.

CONCLUSIONS

Extended thymectomy combined with immunotherapy is a preferred treatment with a satisfactory long-term remission rate. Patients with non-thymomatous myasthenia gravis have a much more promising prognosis than the patients with thymomatous myasthenia gravis. However, appropriate caution must be taken to discontinue pharmaceutical therapy as relapse remains a major concern after a patient who has already undergone thymectomy becomes symptom-free.

Modern impact of video assisted thoracic surgery

With advancement in technology, experience and training over the last two decades, video assisted thoracic surgery (VATS) has become widely accepted and utilized all over the world. VATS started as a diagnostic tool in the early 1990s, technique of VATS lobectomy evolved and became safer over the next 10-15 years and now it is being used for more advanced and hybrid operations. VATS has contributed to the development of minimally invasive surgical interventions for other thoracic disorders like mediastinal tumors and esophageal cancer as well. This article looks at the advantages of VATS, technique advancements and its applications in other thoracic operations and its influence on the present and future of thoracic surgery.

Thoracoscopic versus robotic approaches: advantages and disadvantages

The overall advantages of thoracoscopy over thoracotomy in terms of patient recovery have been fairly well established. The use of robotics, however, is a newer and less proven modality in the realm of thoracic surgery. Robotics offers distinct advantages and disadvantages in comparison with video-assisted thoracoscopic surgery. Robotic technology is now used for a variety of complex cardiac, urologic, and gynecologic procedures including mitral valve repair and microsurgical treatment of male infertility. This article addresses the potential benefits and limitations of using the robotic platform for the performance of a variety of thoracic operations.

Development of the MG-DIS: an ICF-based disability assessment instrument for myasthenia gravis

PURPOSE

To develop a preliminary version of a disease-specific, patient-reported disability assessment instrument for myasthenia gravis (MG) based on the International Classification of Functioning, Disability and Health (ICF): the MG-DIS.

METHODS

Five consecutive steps were taken: literature review and selection of outcome measures; linking of measures' concepts to ICF categories and selection of those reported by 30% of the instruments; comparison of linking results with a previous selection of MG-relevant ICF categories; patient interview; development of questions based on retained ICF categories.

RESULTS

Thirty-one papers containing 21 different outcome measures were found: 13 ICF categories were linked to them. Fifty-five items were retained after the comparison with the list of MG-specific categories, and were used for patient interview. Thirteen interviews were conducted before saturation of data was reached and the final list was composed of 42 categories: based upon them, 44 questions were developed.

CONCLUSIONS

The preliminary version of the MG-DIS contains more information than each single MG-specific tool, in particular, for the component of environmental factors. Further research is needed to test its psychometric properties.

IMPLICATIONS FOR REHABILITATION

It is important that patient-reported outcome is incorporated in MG patient's assessment. MG features can be evaluated with ICF-based methods. An MG-specific patient-reported disability assessment instrument can be used to monitor changes of functioning in patients on MG-specific treatments, and can be used in clinical trials as outcome measure.

Ten-year results of thoracoscopic unilateral extended thymectomy performed in nonthymomatous myasthenia gravis

OBJECTIVE

The aim of this study was to analyze the 10-year results of thoracoscopic unilateral extended thymectomy (TUET) performed in nontumoral myasthenia gravis according to the Myasthenia Gravis Foundation of America recommendations.

BACKGROUND DATA

Thoracoscopic unilateral extended thymectomy has the benefits of a minimally invasive approach. Previous data have shown promising midterm results but long-term results were lacking.

METHODS

Two hundred forty patients with nontumoral myasthenia gravis who underwent surgery between 1999 and 2009 were eligible for the study. The mean follow-up was of 67 months (range: 12-125), 134 patients completed follow-up assessments more than 60 months after TUET.

RESULTS

There were 39 males (16.3%) and 201 females (83.7%), with an age range from 8 to 60 years. The mean preoperative disease duration was 21.5 months. All patients underwent preoperative steroid therapy. Anticholinesterase drugs were required for 123 patients (51.3%), and immunosuppressive drugs were required for 87 (36.3%) patients. The pathologic findings were as follows: normal thymus in 13 patients (5.5%), involuted thymus in 65 patients (27%), and hyperplastic thymus in 162 patients (67.5%). The average weight of the thymus was 110 ± 45 g. Ectopic thymic tissue was found in 147 patients (61.3%). There was no mortality, and morbidity consisted of 12 patients (5%). Complete stable remission was achieved in 61% of the patients, and the cumulative probability of achieving complete stable remission was 0.88 at 10 years.

CONCLUSIONS

With zero mortality, low morbidity, and comparable long-term results to open surgery, TUET can be regarded as the best treatment option for patients undergoing surgery for myasthenia gravis.

Thymectomy for inducing remission in juvenile myasthenia gravis

PURPOSE

The aim of this study was to determine the efficacy of thymectomy to induce remission in juvenile myasthenia gravis.

METHODS

A retrospective review of all patients undergoing a thymectomy for the treatment of juvenile myasthenia gravis was performed at a single tertiary referral centre between 1997 and 2009 (N = 8). All cases were moderate to severe cases (Osserman stage ≥ 2a). All operations were open. Median follow-up was 18 months (range 1-77). Postoperative progress was assessed using the De Filippi classification of remission.

MAIN RESULTS

Only two minor complications were reported. Mean operative time was 120 min (range 80-290 min). Mean postoperative stay was 17 days (range 3-52 days). Remission was observed in 5 of 8 patients (62%) at last known follow up.

CONCLUSIONS

Spontaneous remission rates for myasthenia gravis are quoted to be between 20 and 29% while remission rates following thymectomy are 29-68% at 3 years. Although not all of our patients have had 3 years of follow up-the remission rate of 62% demonstrated by this study is encouraging. If reproducible over a larger series this provides evidence of the efficacy of thymectomy for treating juvenile myasthenia gravis in selected patients.

Quality of life and life circumstances in German myasthenia gravis patients

BACKGROUND

Myasthenia gravis (MG) is a chronic neuromuscular disease. Advances in medical therapy have continuously increased the life expectancy of MG patients, without definitively curing the disease. To analyze life circumstances and quality of life (QoL), a large German MG cohort was investigated.

METHODS AND SAMPLE

In cooperation with the German Myasthenia Association, 2,150 patients with confirmed MG were asked to respond to a mailed questionnaire. The standardized questions related to demographic data, impairments, therapeutic course, use of complementary therapies, illness-related costs, and quality of life (SF-36). In total, 1,518 patients participated, yielding a response rate of 70.6%. The average age was 56.7 years, and the proportion of females 58.6%.

RESULTS

Despite receiving recommended therapy, many patients still suffered from MG-related impairments. In particular, mobility and mental well-being were reduced; moreover, quality of life was markedly reduced. Stepwise linear regression analysis revealed illness stability, impairments, mental conditions, comorbid diseases, and employment to be determinants of QoL.

CONCLUSION

Results indicate that despite prolonged life expectancy among MG patients, health-related quality of life is low. This outcome resulted mainly from impaired mobility and depression. Physical and mental well-being might be improved by additional therapy options. Additionally, health care resources could be used more efficiently in these patients.

Extended videothoracoscopic thymectomy in nonthymomatous myasthenia gravis

Myasthenia gravis (MG) is an uncommon, organ-specific, autoimmune chronic neuromuscular disorder involving the production of autoantibodies directed against the nicotinic acetylcholine receptors (anti-AchRab). It is characterized by weakness and rapid fatigability of voluntary muscles. Thymectomy is performed early in the course of the disease and is indicated for adults less than 70 years old. For many years, the clinical efficacy of thymectomy has been questioned and so far, its benefits in nonthymomatous MG have not been firmly established. Furthermore, the precise mechanisms of action of thymectomy are unknown although possible explanations include removal of the source of continued antigen stimulation and of the AchRab-recruiting B-lymphocytes as well as immunomodulation. However, thymectomy remains indicated in patients with MG and is widely applied to increase the probability of improvement or remission. This article presents the evolution of technical and surgical advances achieved within the authors' program of extended endoscopically assisted thymectomy since 1995. The use of video-assisted thoracic surgery and its variants for performing thymectomy in MG patients is now well established and will continue to evolve for further improvement in the results.

Thymectomy is more effective than conservative treatment for myasthenia gravis regarding outcome and clinical improvement

BACKGROUND

Myasthenia gravis (MG) is an autoimmune disease with a tremendous impact on the quality of life. Controversies over which patients should be operated on because they may benefit most from thymectomy are still ongoing. The aim of this study was to report our long-term results of patients with MG with comparison of thymectomy and conservative treatment.

METHODS

We report a series of 252 patients with MG. Survival data were generated. Patients were seen in the outpatient clinic, where a modified Osserman score and quality of life score were evaluated at the end of the follow-up period for all surviving patients.

RESULTS

A total of 172 patients with MG were followed after thymectomy or with conservative treatment for a median time of 9.8 years. Patients who underwent thymectomy had significantly greater rates of remission and improvement compared with conservative treatment. Furthermore, they had a significantly greater survival.

CONCLUSION

Currently, different effective modalities of treatment are available in patients with MG. In our long-term follow-up, thymectomy was superior to conservative treatment regarding overall survival, clinical improvement, and remission rate. Therefore, thymectomy should be considered strongly for all patients with generalized MG.