Definitions and standard indications of minimally-invasive techniques in thymic surgery

Clinical Application of Thoracoscopic Resection of Anterior Mediastinal Tumors under the Xiphoid Process

Objective

To explore the feasibility and advantages of thoracoscopic resection of anterior mediastinal tumors through subxiphoid and lateral thoracic approaches.

Method

74 patients with anterior mediastinal tumors hospitalized in our hospital from January 2019 to January 2022 were retrospectively analyzed. They were divided into the lateral chest group (31 cases) and the infraxiphoid group (43 cases) according to different operation methods. The tumor size, operation time, intraoperative bleeding, postoperative pain score, postoperative complications, postoperative drainage tube removal time, and hospital stay were compared between the two groups.

Result

The intraoperative bleeding and postoperative pain scores in the subxiphoid group were better than those in the lateral chest group. There was no significant difference in operation time and postoperative complications between the two groups.

Conclusion

Compared with the lateral thoracic approach, the thoracoscopic subxiphoid approach can be more safe and effective in resectioning anterior mediastinal tumors.

Unilateral video-assisted thoracoscopic thymoma resection – Indications, early and mid-term results

Introduction. Thymoma is the most common tumour of the anterior mediastinum. Video-Assisted Thoracic Surgery technique of thymoma resection is spreading world-wide, but the thoracoscopic method is still contentious in many ways. Authors evaluate the early and mid-term results of a 17 years period of VATS unilateral approach at 2 Hungarian thoracic surgical centers. Method. Depending on the anatomical situation of the thymoma, we performed thymectomy, or partial thymectomy (thymomectomy) for the Masaoka–Koga I–II–III stage thymoma from the right or left side through 2 or 3 intercostal ports. We managed the operations with ultrasonic dissector and electrocauter. By using international standards we evaluated perioperative morbidity, mid-term oncological results and clinical symptoms of myasthenia. Results. 23 of the 54 patients were man, 31 were woman, the average age was 58 (26–79) years, 23 of them had myasthenia. The conversion rate was 11,5% (7/61). The average operation time was 84 (39–150) minutes. The average hospitalisation time was 5.5 (3–19) days. The average size of the thymomas was 46 (18–90) mm. The histology resulted thymoma type A in 2 cases, AB in 19 cases, B1/2/3 in 11/11/1 cases, mixed B in 10 cases. The examination of the resection line was R0/1/2 in 42/11/1 cases. The Masaoka–Koga stages were: I (17), IIA (28), IIB (2), III (7). There was 25 thymomectomies, and 29 thymectomies. In seven cases there were extension of the operation to the pericardium (2), to the lung (2), to the phrenic nerve (6), and to innominate vein (1). The in-hospital mortality over 30 day was in 1 case (1.85%). The morbidity was 11/54 (20.4%). The average follow-up time was 62.56 (5–198) months. In the group with myasthenia the effectivity of the operation was 18/21 (85.7%), including complete remission of 5/21 (23.8%). Post-thymectomy myasthenia gravis developed in 2/31 cases (6.5%). The average 5 years survival was 100%, tumour-free 5 years survival was 96%. Conclusions. The higher proportion of the thymomectomy in the early results, higher conversion rate and lower R0 proportion might be in connection with the attitude of the surgeons, with the learning curve and with the limitations of the unilateral method. After a longer follow-up time late results may become more real and comparable. Instead of unilateral VATS technique we have changed to the subxyphoideal approach of VATS because of its better visualisation.

Impact of the Surgical Approach to Thymectomy Upon Complete Stable Remission Rates in Myasthenia Gravis: A Meta-analysis

OBJECTIVES

To determine whether the available operative techniques for thymectomy in myasthenia gravis (MG) confer variable chances for achieving complete stable remission (CSR), we performed a meta-analysis of comparative studies of surgical approaches to thymectomy.

METHODS

Meta-analysis was done of all studies providing comparative data on thymectomy approaches, with CSR reported and minimum 3-year mean follow-up.

RESULTS

Twelve cohort studies and 1 randomized clinical trial, containing 1,598 patients, met entry criteria. At 3 years, CSR from MG was similar after video-assisted thoracoscopic (VATS) extended vs both basic (relative risk [RR] 1.00, p = 1.00, 95% confidence interval [CI] 0.39-2.58) and extended (RR 0.96, p = 0.74, 95% CI 0.72-1.27) transsternal approaches. CSR at 3 years was also similar after extended transsternal vs combined transcervical-subxiphoid (RR 1.08, p = 0.62, 95% CI 0.8-1.44) approaches. VATS extended approaches remained statistically equivalent to extended transsternal approaches through 9 years of follow-up (RR 1.51, p = 0.05, 95% CI 0.99-2.30). The only significant difference in CSR rate between a traditional open and a minimally invasive approach was seen at 10 years when the now-abandoned basic (non-sternum-lifting) transcervical approach was compared to the extended transsternal approach (RR 0.4, p = 0.01, 95% CI 0.2-0.8).

CONCLUSIONS

A significant difference in the rate of CSR among various surgical approaches for thymectomy in MG was identified only at long-term follow-up and only between what might be considered the most aggressive approach (extended transsternal thymectomy) and the least aggressive approach (basic transcervical thymectomy). Extended minimally invasive approaches appear to have CSR rates equivalent to those of extended transsternal approaches and are therefore appropriate in the hands of experienced surgeons.

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'.

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.