The Impact Of Thymectomy In Thymomatous And Nonthymomatous Myasthenia Gravis - The Experience Of A Tertiary Center.

INTRODUCTION: Thymectomy remains a mainstay of treatment in Thymomatous (T) and Nonthymomatous (nT) Myasthenia Gravis (MG), with improved clinical outcomes and reduced need for medical treatment, however, there is little research regarding long-term follow-up. We aim to assess the impact of surgery on the long-term outcome of patients with MG at our center. METHODS: Retrospective analyses of MG patients submitted to thymectomy between 2007 and 2017 at the thoracic surgery department of CHUC. Clinical assessment was performed according to the MG Foundation of America (MGFA) Clinical Classification (cMGFA). The follow-up was categorized according to the MGFA Post-intervention Status (MGFA-PIS) and cMGFA. Statistical analysis was performed with SPSS, to a significance level of 5%. RESULTS: Thirty-seven patients underwent extended thymectomy and 67.6% were female. Median age at diagnosis was 46.68±19.2 years. Most patients (83.8%) had anti-acetylcholine receptor antibodies and 81.1% had generalized forms of MG. Many patients (67.6%) had surgery less than 12 months after the clinical diagnosis. TMG was present in 19 (51.4%) patients. Compared to nTMG, these patients were older (54.06±17.9 vs 40.17±19.4 years) and most were men (52.9% vs 16.7%). We obtained a good outcome in most patients in the first (81.1%), second (86.1%), and fifth (84.8%) year of follow-up. There was a shift towards better prognosis categories in the good outcome group: 9.1% CSR, 3.0% PR, and 66,7% MM in the fifth year. Preoperative medical treatment did not influence the long-term follow-up outcome. A shorter time to surgery (< 12 months) correlated with better outcomes at year 5 (p=0.016). CONCLUSION: Thymectomy led to a sustained clinical improvement in our cohort, allowing for a reduced need for medication. A shorter time to surgery seems to have a positive influence on long-term prognosis. We expect that an extended follow-up would improve our results.

Robot-assisted surgery outperforms video-assisted thoracoscopic surgery for anterior mediastinal disease: a multi-institutional study.

Anterior mediastinal procedures are increasingly being performed using robot-assisted thoracic surgery (RATS) or video-assisted thoracoscopic surgery (VATS). While both approaches have shown superior outcomes compared to open surgery, their comparative benefits are not as distinct. The aim of this retrospective study was to bridge this knowledge gap using a multicenter dataset. Patients who underwent elective minimally invasive surgery for anterior mediastinal disease between 2015 and 2022 were deemed eligible. The study participants were grouped based on whether a robot was used or not, and perioperative outcomes were compared. To mitigate selection bias, inverse probability of treatment weighting (ITPW) was applied using the propensity score. The final analysis included 312 patients (RATS = 120; VATS = 192). Following the application of IPTW, RATS was found to be associated with a longer operating time (215.3 versus 139.31 min, P < 0.001), fewer days with a chest tube (1.96 versus 2.61 days, P = 0.047), and a shorter hospital stay (3.03 versus 3.91 days, P = 0.041) compared to VATS. Subgroup analyses indicated that the benefit of RATS in reducing the length of hospital stay was particularly pronounced in patients with tumors larger than 6 cm (mean difference [MD] = - 2.28 days, P = 0.033), those diagnosed with myasthenia gravis (MD = - 3.84 days, P = 0.002), and those who underwent a trans-subxiphoid surgical approach (MD = - 0.81 days, P = 0.04). Both VATS and RATS are safe and effective approaches for treating anterior mediastinal disease. However, RATS holds distinct advantages over VATS including shorter hospital stays and reduced chest tube drainage periods.

Thymoma negatively affects the neurological outcome of myasthenia gravis after thymectomy: a propensity score matching study.

BACKGROUND: Thymoma and myasthenia gravis (MG) interact with each other. This study aimed to evaluate the effects of thymoma on neurological outcome of MG patients after thymectomy using the propensity score matching (PSM) method. METHODS: Consecutive patients with MG who underwent thymectomy at Beijing Hospital between January 2012 and August 2021 were retrospectively enrolled. Clinical and follow-up data were collected. Statistical analysis was performed using SPSS 23.0 software. PSM was performed to eliminate selection bias. RESULTS: A total of 456 patients were included in this study. Thymoma was present in 138 (30.3%) patients. The median follow-up time was 72 (range, 12-135) months. At the last follow-up, a lower proportion of thymomatous MG patients achieved complete stable remission (CSR) compared with non-thymomatous MG patients (P = 0.011), and the effective rate [CSR + pharmatologic remission (PR) + minimal manifestations (MM)] of thymomatous MG patients was also lower (P = 0.037). Considering time to CSR, Kaplan-Meier analysis showed thymomatous MG patients had lower cumulative CSR rate than non-thymomatous MG patients (log-rank, P = 0.019). After PSM, 105 pairs of patients were matched successfully. For the matched patients, thymomatous MG patients had a lower CSR rate and a lower effective rate (P = 0.002, 0.039, respectively), and K-M analysis still showed thymomatous MG patients had lower cumulative CSR rate (log-rank, P = 0.048). Multivariate Cox analysis demonstrated that thymoma (HR: 0.592, 95% CI 0.389-0.900, P = 0.014), older age at the time of surgery (HR: 0.971, 95% CI 0.953-0.990, P = 0.003), and preoperative course of MG > 12 months (HR: 0.474, 95% CI 0.317-0.708, P = 0.000) were negative predictive factors for CSR. CONCLUSIONS: Thymoma had a negative effect on the neurological outcome of MG after thymectomy. MG patients with old age and a preoperative course of longer than one year had a lower probability of achieving CSR.

Robot versus video-assisted thoracoscopic thymectomy for large thymic epithelial tumors: a propensity-matched analysis.

BACKGROUND: Both video-assisted thoracoscopic surgery (VATS) thymectomy and robot-assisted thoracoscopic surgery (RATS) thymectomy have been suggested as technically sound approaches for early-stage thymic epithelial tumors. However, the choice of VATS or RATS thymectomy for large and advanced thymic epithelial tumors remains controversial. In this study, the perioperative outcomes of VATS and RATS thymectomy were compared in patients with large thymic epithelial tumors (size ≥5.0 cm). METHODS: A total of 113 patients with large thymic epithelial tumors who underwent minimally invasive surgery were included. Sixty-three patients underwent RATS, and 50 patients underwent VATS. Patient characteristics and perioperative variables were compared. RESULTS: Compared with the VATS group, the RATS group experienced a shorter operation time (median: 110 min vs.130 min; P < 0.001) and less blood loss (30.00 ml vs. 100.00 ml, P < 0.001). No patients in the RATS group needed conversion to open surgery, but in the VATS series, five patients required conversion to open procedures (0% vs. 14.29%, P = 0.054). The rate of concomitant resection in the RATS group was similar to that in the VATS group (11.43% vs. 5.71%; P = 0.673). There was no significant difference between the two groups in the duration of chest tube (P = 0.587), postoperative complications (P = 1.000), and the duration of postoperative hospital stay (P = 0.141). CONCLUSION: For large thymic epithelial tumors, RATS thymectomy can be performed safely and effectively in a radical fashion. Due to the advanced optics and precise instrument control, concomitant resections can be easily achieved in larger thymic epithelial tumors using the robotic approach.

Propofol TCI or sevoflurane anesthesia without muscle relaxant for thoracoscopic thymectomy in myasthenia gravis patients: a prospective, observational study.

BACKGROUND: Myasthenia gravis (MG) patients interact unpredictably with anesthetic agents, including neuromuscular blocking agents. Here, we investigate the effectiveness of general anesthesia without muscle relaxants using either propofol via target-controlled infusion systems (TCI) or sevoflurane in MG patients undergoing thoracoscopic thymectomy. METHODS: This prospective, open-label, observational study was conducted in a university hospital. We included 90 myasthenic patients undergoing thoracoscopic thymectomy with general anesthesia. Patients received induction and maintenance anesthesia with propofol TCI (group P, n = 45) or induction with propofol 2-3 mg.kg-1 and maintenance anesthesia with sevoflurane (group S, n = 45). In both groups, the procedure was performed under the guidance of entropy with sufentanil but not a muscle relaxant. Intubation conditions, hemodynamic changes, respiratory function, neuromuscular transmission, arterial blood gas, and complications were evaluated. RESULTS: All patients achieved good intubation conditions. Hemodynamic instability was more frequent in group S than in group P, mostly in the induction stage, and was controllable. The reduction in the intraoperative train-of-four ratio from baseline at 30 min, 60 min, and 90 min in group S was 10.3%, 14.2%, and 14.3%, respectively, significantly higher than that in group P (6.8%, 7.2%, and 8.4%, respectively), which completely recovered at the end of the surgery. All patients were extubated in the operating room without complications. No other significant differences between the groups were observed. CONCLUSIONS: Anesthesia with propofol TCI or sevoflurane without muscle relaxants in MG patients offered safe and effective conditions for thoracoscopic thymectomy. Sevoflurane achieved higher levels of intraoperative muscular relaxation than propofol TCI. Postoperative neuromuscular function was not affected by these anesthetics.

Serum metabolomics of treatment response in myasthenia gravis.

OBJECTIVE: High-dose prednisone use, lasting several months or longer, is the primary initial therapy for myasthenia gravis (MG). Upwards of a third of patients do not respond to treatment. Currently no biomarkers can predict clinical responsiveness to corticosteroid treatment. We conducted a discovery-based study to identify treatment responsive biomarkers in MG using sera obtained at study entry to the thymectomy clinical trial (MGTX), an NIH-sponsored randomized, controlled study of thymectomy plus prednisone versus prednisone alone. METHODS: We applied ultra-performance liquid chromatography coupled with electro-spray quadrupole time of flight mass spectrometry to obtain comparative serum metabolomic and lipidomic profiles at study entry to correlate with treatment response at 6 months. Treatment response was assessed using validated outcome measures of minimal manifestation status (MMS), MG-Activities of Daily Living (MG-ADL), Quantitative MG (QMG) score, or a strictly defined composite measure of response. RESULTS: Increased serum levels of phospholipids were associated with treatment response as assessed by QMG, MMS, and the Responders classification, but all measures showed limited overlap in metabolomic profiles, in particular the MG-ADL. A panel including histidine, free fatty acid (13:0), γ-cholestenol and guanosine was highly predictive of the strictly defined treatment response measure. The AUC in Responders' prediction for these markers was 0.90 irrespective of gender, age, thymectomy or baseline prednisone use. Pathway analysis suggests that xenobiotic metabolism could play a major role in treatment resistance. There was no association with outcome and gender, age, thymectomy or baseline prednisone use. INTERPRETATION: We have defined a metabolomic and lipidomic profile that can now undergo validation as a treatment predictive marker for MG patients undergoing corticosteroid therapy. Metabolomic profiles of outcome measures had limited overlap consistent with their assessing distinct aspects of treatment response and supporting unique biological underpinning for each outcome measure. Interindividual variation in prednisone metabolism may be a determinate of how well patients respond to treatment.

[Robot-assisted Thoracoscopic Surgery for Mediastinal Tumor in Our Department].

In 2019, our facility introduced robot-assisted surgery for mediastinal tumors using da Vinci Si, which was upgrade to da Vinci X and Xi in 2021. Initially, the unilateral thoracic cavity approach was used for robot-assisted surgeries. The unilateral approach has the advantage of facilitating the anatomical recognition of either the left or right side, with the side used selected depending on the location of the lesion. Notably, challenges such as difficulty in recognizing objects were still encountered. To compensate for these shortcomings, our hospital introduced robotic subxiphoid-optical thymectomy, a subxiphoid approach, which has been used for all robot-assisted mediastinal tumor surgeries since its introduction under the guidance of Kyoto Prefectural University of Medicine. Additionally, extended thymectomy, which has been covered by insurance since 2020 and used as the standard surgical procedure for robot-assisted mediastinal tumor surgery at our department, can be performed using the same approach.

[Robot-assisted Minimally Invasive Surgery for Mediastinal Tumors].

The subxiphoid approach in thymectomy provides better visibility around the left brachiocephalic vein than the lateral thoracic approach. Robot-assisted thoracoscopic surgery is easier to parform than video- assisted thoracoscopic surgery for surgery of the upper mediastinum, because the forceps can be moved with many joints. Robot-assisted thymectomy using the subxiphoid approach may be less traumatic and less invasive than median sternotomy. We must continue to devise surgical procedures to make oncologically curative surgery more minimally invasive.

[Robot-assisted Extended Thymectomy via a Bilateral Approach for Patients with Myasthenia Gravis].

Extended thymectomy is a procedure to remove the thymus gland and surrounding adipose tissue, while the traditional approach via a median sternotomy, minimally invasive approaches such as video-assisted thoracoscopic surgery (VATS) and robot-assisted thoracoscopic surgery (RATS) have been adopted. This report described the technique of bilateral approach for extended thymectomy in patients with myasthenia gravis (MG) by robot-assisted thoracoscopic surgery, and also showed the perioperative outcomes and postoperative exacerbation rates of 11 patients. In most patients, score of MG symptom were reduced and levels of anti-acetylcholine receptor antibodies declined postoperatively. In a small number of cases, the safety and efficacy of a RATS bilateral approach for extended thymectomy were confirmed.

[Minimally Invasive Surgery for Mediastinal Diseases in Our Institute:Innovations and Surgical Practice].

Since the early 1990s, minimally invasive surgery has been introduced in many surgical fields. The progress of technology and increased interest in minimally invasive surgery has led to innovation from surgery with a large incision to complete thoracoscopic surgery in many facilities. We started thoracoscopic mediastinal surgery in 1997 and robot-assisted mediastinal surgery in 2021. Considering the approach for anterior mediastinal tumor resection, it is necessary to fully understand tumor size, tumor location, and the existence of the tumor invasion to other organs. Especially in the case of tumors located on the cranial side above the innominate vein or thymectomy with dissection of the superior pole of the thymus, ensuring surgical field visibility is essential. In our institute, from the point of cosmetics, surgical field visibility is ensured using carbon dioxide insufflation and a sternum-lifting method. Although the number of cases is limited, we report our ingenuity and actual implementation of the techniques.

[Surgical Procedure and Perioperative Outcomes of Three-port Video-assisted Thoracoscopic Surgery Thymectomy for Thymoma, Including en-bloc Resection of Adjacent Organs].

This report discusses the treatment and outcomes of three-port video-assisted thoracoscopic surgery (VATS) thymectomy for thymoma. We reviewed perioperative results of 159 thymoma cases( excluding thymic carcinoma) over 16 years. Thoracoscopic surgery was indicated for Masaoka stagesⅠ to Ⅲ, tumor diameter up to 12 cm, and resection of surrounding organs up to the lung, pericardium+reconstruction, internal thoracic artery and vein, left brachiocephalic vein, and phrenic nerve+reconstruction. The mean age of patients was 56.9±12.7, with 71 males and 88 females. The surgical approach was right-sided in 110 cases, left-sided in 47 cases, and bilateral in 2 cases. Total thymectomy was performed in 141 cases, with total thymectomy plus combined resection of other organs (lungs, pericardium, and phrenic nerve) ±reconstruction in 18 cases. The World Health Organization( WHO) classification( 5th edition) was type A/AB/B1/B2/B3/micronodular thymoma with lymphoid stroma (MNTLS) = 20/49/32/45/11/2, and Masaoka classification was stageⅠ/Ⅱ/Ⅲ=69/86/4. The three-port VATS technique offers several advantages, including its applicability to other surgeries, avoidance of contralateral thoracic cavity opening, safety in thymectomy without open conversion, and a mean postoperative hospital stay of 3 days.

[Validity of Video-assisted Thoracic Surgery for Thymoma].

OBJECTIVES: This study aimed to identify the validity of video-assisted thoracic surgery (VATS) for thymoma, including myasthenia gravis( MG). METHODS: A total of 20 patients who underwent VATS for thymoma at our institution between 2011 and 2019 were included in the study. Preoperative complications and prognosis were analyzed to detect the safety and efficiency of VATS thymectomy. MG improvement after VATS extended thymectomy was evaluated using a quantitative myasthenia gravis score( QMGS) and Myasthenia Gravis Foundation of America post-intervention status( MGFA-PIS). RESULTS: The median tumor size was 2.6 cm (range, 1.0-8.0 cm). All thymomas were classified as TNM stageⅠ. Two patients had type A thymoma, five had type AB, six had type B1, six had type B2, and one had type B3. Postoperative complications were only observed in one patient with pneumonia. The median follow-up period was 5.1 years;no recurrence and disease-related deaths were observed. However, three patients died of other diseases. In patients with MG, postoperative crisis was not observed, and the symptoms improved in all the patients as evaluated by QMGS and MGFA-PIS. CONCLUSIONS: VATS thymectomy and VATS extended thymectomy for patients with thymoma may be effective methods to improve not only prognosis but also MG, provided the range of resections are comparable to that of conventional open surgery.

A Propensity Score-Matching Analysis: Robotic Thymectomy Through the Subxiphoid Has Advantages Over Video-Assisted Thymectomy Surgery.

Objective: The purpose of this article is to evaluate the security and effectiveness of subxiphoid and subcostal robot-assisted thoracoscopic thymectomy (S-RATT) and compare it with subxiphoid and subcostal video-assisted thoracoscopic thymectomy (S-VATT) in terms of short-term perioperative results and costs. Methods: A retrospective study was carried out on 62 individuals who had undergone successful complete thymectomy for anterior mediastinal disease using subxiphoid and subcostal arch approaches. Propensity score-matching analysis was utilized between the two groups, and the perioperative outcomes were compared. Results: The S-RATT group exhibited less intraoperative blood loss (20 ± 15.35 versus 69.55 ± 69.54, P < .001), lower levels of C-reactive protein (112.38 ± 68.08 versus 72.58 ± 42.62, P = .027), and lower postoperative pain scores (2.09 ± 1.54 versus 4.27 ± 1.28, P < .001). However, the hospitalization costs of patients in the S-VATT group were found to be lower than those in the S-RATT group (33,802.41 ± 8785.05 versus 49,977.53 ± 20,221.79, P < .001). Conclusions: S-RATT appears to be a viable and secure method for managing anterior mediastinal tumors.

Thymectomy in severe (Myasthenia Gravis Foundation of America classes IV-V) generalized myasthenia gravis: is the game really worth the candle?

OBJECTIVES: Total thymectomy in addition to medical treatment is an accepted standard therapy for myasthenia gravis (MG). Patients with severe generalized MG present life-threatening events, poor prognosis and higher risk of postoperative myasthenic crisis. The aim of our study is to investigate neurological and surgical results in patients with Myasthenia Gravis Foundation of America (MGFA) class IV and V MG following thymectomy. METHODS: Data on 76 MG patients with preoperative MGFA classes IV and V who underwent thymectomy were retrospectively collected. Primary end points included short-term surgical outcomes and long-term neurological results including the achievement of complete stable remission and any improvement as defined by MGFA Post-Intervention Status criteria. RESULTS: There were 27 (35.5%) males and 49 (64.5%) females; 53 (69.7%) were classified as MGFA class IV and 23 (30.3%) as class V. Thymectomy was performed through sternotomy in 25 (32.9%) patients, Video-assisted thoracic surgery (VATS) in 5 (6.6%) and Robot-assisted thoracic surgery (RATS) in 46 (60.5%). The median operative time was 120 (interquartile range: 95; 148) min. In-hospital mortality was observed in 1 (1.3%) patient and postoperative complications in 14 (18.4%) patients. The median postoperative hospital stay was 4 (interquartile range: 3; 6) days. Pathological examination revealed 31 (40.8%) thymic hyperplasia/other benign and 45 (59.2%) thymomas. Cumulative complete stable remission and improvement probabilities were 20.6% and 83.7% at 5 years and 66.9% and 97.6% at 10 years, respectively. A significant improvement rate was found in patients with age at the time of thymectomy of ≤50 years (P = 0.0236), MGFA class V (P = 0.0154) and acetylcholine receptor antibodies positivity (P = 0.0152). CONCLUSIONS: Thymectomy in patients with severe MG yields good perioperative outcomes and satisfactory long-term neurological improvement, especially for patients younger than 50 years, with MGFA class V and anti-AChR+ MG.

Early Postoperative Results after Thymectomy for Thymic Cancer: A Single-Institution Experience.

BACKGROUND: Surgery for thymic cancers is considered the key of curative treatment. Preoperative patients' characteristics and intraoperative features might influence postoperative outcome. We aim to verify short-term outcomes and possible risk factors for complications after thymectomy. METHODS: We retrospectively investigated patients undergoing surgery for thymoma or thymic carcinoma in the period between January 1, 2008, and December 31, 2021, in our department. Preoperative features, surgical technique (open, bilateral VATS, RATS), intraoperative characteristics and incidence of postoperative complications (PC) were analyzed. RESULTS: We included in the study 138 patients. Open surgery was performed in 76 patients (55.1%), in 36 VATS (26.1%) and in 26 RATS (36.1%). Resection of one or more adjacent organs due to neoplastic infiltration was required in 25 patients. PC appeared in 25 patients (52% Clavien-Dindo grade I, 12% grade IVa). Open surgery had a higher incidence of PC (p < 0.001), longer postoperative in-hospital stay (p = 0.045) and larger neoplasm (p = 0.006). PC were significant related to pulmonary resection (p = 0.006), phrenic nerve resection (p = 0.029), resection of more than one organ (p = 0.009) and open surgery (p = 0.001), but only extended surgery of more organs was confirmed as independent prognostic factor for PC (p = 0.0013). Patients with preoperative myasthenia symptoms have a trend toward stage IVa complications (p = 0.065). No differences were observed between outcomes of VATS and RATS. CONCLUSIONS: Extended resections are related to a higher incidence of PC, while VATS and RATS guarantee a lower incidence of PC and shorter postoperative stay even in patients that require extended resections. Symptomatic myasthenia patients might have a higher risk toward more severe complications.

Perioperative outcomes of minimally invasive surgery for large malignant thymic epithelial tumors and for total thymectomy.

PURPOSE: Minimally invasive surgery (MIS) for thymic tumors is now accepted widely, in line with improved surgical techniques; however, we occasionally encounter complicated cases of large tumors or of total thymectomy requiring prolonged operative duration or conversion to an open procedure (OP). We reviewed patients registered in a nationwide database to identify the technical feasibility of MIS for thymic epithelial tumors. METHODS: Data on patients treated surgically between 2017 and 2019 were extracted from the National Clinical Database of Japan. Clinical factors and operative outcomes were calculated by tumor diameter using trend analyses. Perioperative outcomes of MIS for non-invasive thymoma were investigated using propensity score-matched analyses. RESULTS: MIS was performed in 46.2% of the patients. The operative duration and conversion rate increased with the tumor diameter (p < .001). After propensity score-matching, operative duration and postoperative hospital stay were shorter (p < .001), and the transfusion rate was lower (p = .007) in patients who underwent MIS than in those who underwent OP for thymomas ≥ 5 cm. Among patients who underwent total thymectomy, blood loss was less (p < .001) and the postoperative hospital stay was shorter (p < .001) in those who underwent MIS than in those who underwent OP. There were no significant differences in postoperative complications and mortality. CONCLUSIONS: MIS is technically feasible even for large non-invasive thymomas or for total thymectomy, although the operative duration and open conversion rate increase with the tumor diameter.

The Duke Myasthenia Gravis Clinic Registry: II. Analysis of outcomes.

INTRODUCTION/AIMS: The Duke Myasthenia Gravis (MG) Clinic Registry contains comprehensive physician-derived data on patients with MG seen in the Duke MG Clinic since 1980. The aim of this study was to report outcomes in patients seen in the clinic and treated according to the International Consensus Guidance statements. METHODS: This is a retrospective cohort study of patients initially seen after 2000 and followed for at least 2 years in the clinic. Treatment goal (TG) was defined as achieving MGFA post-intervention status of "minimal manifestations" or better; PIS was determined by the treating neurologist. Time-to-event analysis, including Cox proportional hazards modeling, was performed to assess the effect of sex, acetylcholine receptor antibody (AChR-Ab) status, age at disease onset, distribution (ocular vs generalized), thymectomy, and thymoma on the time to achieve TG. RESULTS: Among the 367 cohort patients, 72% achieved TG (median time less than 2 years). A greater proportion of patients with AChR-Abs and thymectomy achieved TG and they did so sooner than patients without these antibodies or thymectomy. Otherwise, there were no significant differences in these findings within the tested subgroups. The disease duration at the first Duke Clinic visit was shorter in patients who achieved TG than in those who did not. DISCUSSION: These results demonstrate outcomes that can be achieved in patients with MG treated according to the current Consensus Guidance statements. Among other things, they can be used to determine the added value and potential role of new treatment modalities developed since 2018.

Analysis of influencing factors of perioperative myasthenic crisis in 387 myasthenia gravis patients without thymoma in a single center.

OBJECTIVE: To study the influencing factors of myasthenic crisis in non-thymoma myasthenia gravis (MG) patients during perioperative period. METHODS: We retrospectively analyzed a total of 387 non-thymoma MG patients who underwent extended thymoma resection in the Department of Thoracic Surgery of Beijing Hospital from February 2011 to December 2021, recorded ASA score, Osserman classification, preoperative course, pyridostigmine dosage, operation method, operation time, and intraoperative blood loss, then analyzed the factors associated with postoperative myasthenic crisis by univariate and multivariate logistic regression. RESULTS: Osserman classification IIB + III + IV (P < 0.001), history of myasthenic crisis (P = 0.013), pyridostigmine dosage greater than 240 (P < 0.001), ASA score 2 and 3 (P = 0.001) are independent risk factors for myasthenic crisis. CONCLUSION: Patients with poor Osserman classification, history of myasthenic crisis before surgery, larger preoperative dosage of pyridostigmine, and higher ASA scores should be highly alert to the occurrence of postoperative myasthenic crisis.

Minimally Invasive Thymectomy Could Be Attempted for Locally Advanced Thymic Malignancies: A Real-World Study With Propensity Score-Matched Analysis.

INTRODUCTION: Increasing evidence supports minimally invasive thymectomy (MIT) for early stage thymic malignancies than open median sternotomy thymectomy (MST). Nevertheless, whether MIT could be attempted for locally advanced disease remains unclear. METHODS: The clinical data of consecutive patients with stage T2-3NxM0 (eighth edition TNM staging) thymic malignancies who underwent MIT or MST were identified from a prospectively maintained database. The co-resected structures were rated with a resection index to evaluate surgical difficulty. The impact of surgical approach on treatment outcomes was investigated through propensity score-matched analysis and multivariable analysis. RESULTS: From January 2008 to December 2019, a total of 128 patients were included; MIT was initially attempted in 58 (45.3%) cases, and eight (13.8%) were converted to MST during surgery. The conversion group had similar perioperative outcomes to the MST group, except for a longer operation time. After propensity score matching, the resection index scores were similar between the MIT and MST groups (3.5 versus 3.7, p = 0.773). The MIT group had considerably less blood loss (p < 0.001), fewer postoperative complications (p = 0.048), a shorter duration of chest drainage (p < 0.001), and a shorter hospitalization duration (p < 0.001) than the MST group. The 5-year freedom from recurrence rate was not different between the two groups (78.2% versus 78.5%, p = 0.942). In multivariable analysis, surgical approach was not associated with freedom from recurrence (p = 0.727). CONCLUSIONS: MIT could be safely attempted in carefully selected patients with locally advanced thymic tumors. Conversion did not compromise the surgical outcomes. Patients may benefit from the less traumatic procedure and thus better recovery, with comparable long-term oncologic outcomes.

Safety and feasibility of a modularized procedure for trans-subxiphoid robotic extended thymectomy.

BACKGROUND: The purpose of this study was to introduce an "eight-step modularized procedure (M-RET)" for trans-subxiphoid robotic extended thymectomy for patients with myasthenia gravis (MG). Its safety and feasibility were further verified in this study. MATERIALS AND METHODS: This retrospective study included 87 consecutive MG patients who underwent trans-subxiphoid robotic extended thymectomy at our institution between September 2016 and August 2021. According to different resection models, patients were divided into two groups: traditional trans-subxiphoid robotic extended thymectomy group (T-RET group) and eight-step modularized technique group (M-RET group). Baseline demographic characteristics and operation-related parameters were collected and compared between the two groups. RESULTS: There were 41 (47.1%) patients in the M-RET group and 46 (52.9%) patients in the T-RET group. The M-RET group resected a greater amount of mediastinal adipose tissues and required more dissection time (median and interquartile range: 135.0, 125.0 to 164.0 v. 120.0, 105.0 to 153.8, P = 0.006) compared with the T-RET group. There were no statistically significant differences in terms of the intraoperative blood loss, duration of chest drainage, length of hospital stay, and postoperative complications between the two groups. There was no mortality or conversion in each of the two groups and all patients recovered well upon discharge. CONCLUSION: The eight-step modularized technique of trans-subxiphoid robotic extended thymectomy was verified to be a safe, effective, radical procedure, which offers unique superiority over ectopic thymic tissue resection.