Inclusion of the transcervical approach in video-assisted thoracoscopic extended thymectomy (VATET) for myasthenia gravis: a prospective trial

A proof-of-concept study: advantages of the subxiphoid over the lateral intercostal approach

OBJECTIVES

The study was designed to evaluate the superiority of the subxiphoid approach compared with the lateral intercostal approach during the operation and other perioperative indices.

METHODS

Patients diagnosed with anterior mediastinal disease in our hospital between January 2018 and October 2019 were prospectively assigned to 2 groups; 1 group underwent the lateral intercostal approach and 1 group underwent the subxiphoid approach of video-assisted thoracoscopic surgery to resect the diseased tissue. The PaCO2, SaO2, PaO2 and circulation changes were recorded during the operation; the neutrophil-to-lymphocyte ratio and other perioperative outcomes, including clinical and surgical results, operating time, blood loss, postoperative complication and postoperative pain score were compared.

RESULTS

A total of 59 patients diagnosed with an anterior mediastinal tumour or myasthenia gravis underwent a video-assisted thoracoscopic resection. Thirty-one patients were treated via the subxiphoid approach, and 28 patients were treated via the lateral intercostal approach. The PaCO2 increased significantly and the SaO2 remained stable in the subxiphoid group during the operation, whereas PaCO2 increased significantly and SaO2 decreased at the same time in the lateral intercostal group. Operations were more frequently interrupted for the hypoxia or circulation disturbance during the process of dissecting the thymus in the lateral intercostal approach. Compared with the lateral intercostal approach, patients treated via the subxiphoid approach experienced less inflammation and exhibited lower pain scores and shorter postoperative hospital stays. There were no significant differences in postoperative complications between the 2 groups. All of the patients recovered well when discharged.

CONCLUSIONS

Our study results suggested that the subxiphoid approach has less of an influence on the pulmonary circulation than the lateral intercostal approach, that the whole procedure is safer and easier and that the subxiphoid approach may be the ideal choice for patients with anterior mediastinal disease.

Subxiphoid and subcostal arch versus unilateral video-assisted thoracic surgery approaches to thymectomy for myasthenia gravis

PURPOSE

Thymectomy is an important treatment for myasthenia gravis (MG). We conducted this study to compare the clinical outcomes of the recently introduced subxiphoid and subcostal arch thymectomy (SASAT) approach with those of the standard unilateral video-assisted thoracoscopic surgery (VATS).

METHODS

We analyzed, retrospectively, the perioperative, and long-term outcomes of 179 consecutive MG patients (age 18-65 years), who underwent SASAT or unilateral VATS-extended thymectomy between July, 2012 and May, 2019.

RESULTS

All demographic and clinical characteristics were comparable in the two groups. The median surgical time, estimated blood loss, thoracotomy conversion rate, total and chest drainage, and complications did not differ significantly between the groups. The visual analog scale (VAS) score was significantly lower in the SASAT group. Complete stable remission (CSR) was achieved in a significantly larger proportion of the SASAT group patients and was significantly higher in women than in men. The Quantitative MG score was significantly lower in the SASAT group. Patients in the MG Foundation of America Clinical Classification groups I and II achieved better remission rates than those in groups III-V.

CONCLUSIONS

SASAT is a safe and feasible MG treatment, which may yield better outcomes than unilateral VATS and improve the quality of treatment.

Transareolar uniportal thoracoscopic extended thymectomy for patients with myasthenia gravis

Background

Transareolar uniportal thoracoscopic extended thymectomy (TUTET) has not been previously reported. We attempted to assess the feasibility and safety of TUTET for male myasthenia gravis (MG) patients.

Patients and methods

From February 2013 to February 2020, 46 men with MG underwent TUTET. All patients were followed up for 12–84 months postoperatively by clinic visits or telephone/e-mail interviews.

Results

All surgeries were completed successfully, with an average operation time of 72.6 min. The mean length of transareolar uniportal incision was 3.0 ± 0.4 cm, and the mean postoperative cosmetic score was 3.1 ± 0.5 at discharge. Three months postoperatively, no patients had an apparent surgical scar on the chest wall or complained of postoperative pain. Substantial amelioration of the disease was achieved in a short period, and several benefits were clear. At the 1-year follow-up, all patients showed a good cosmetic effect and high satisfaction.

Conclusions

TUTET is an effective and safe way for men with MG. The uniportal incision is hidden in the areola with sound cosmetic effects. We believe that TUTET is an acceptable procedure for extended thymectomy.

Perioperative outcomes and mid-term effects in performing video-assisted thoracoscopic extended thymectomy for myasthenia gravis: subxiphoid versus right thoracic approaches

Background

Approaches of thoracoscopic thymectomy for myasthenia gravis (MG) are debatable. The subxiphoid approach is widely utilized recent years for its better visualization of the anterior mediastinum. In the present study, we compared perioperative outcomes and mid-term effects of the extended thymectomy for MG between the subxiphoid approach and the routine right-thoracic approach.

Methods

One hundred and thirty-one MG patients treated with thoracoscopic extended thymectomy were analyzed. Among them, 68 patients were operated on via the subxiphoid approach and the other 63 via the conventional right-side unilateral approach. The patient outcomes were retrospectively reviewed and evaluated. Mid-term clinical outcome was assessed according to the classification system proposed by the Myasthenia Gravis Foundation of America (MGFA). Clinical efficacy and variables influencing outcome were evaluated by the Kaplan-Meier method and Cox proportional hazards regression analysis.

Results

Compared with the right thoracic approach, the duration of the procedure via the subxiphoid approach was significantly shorter (P=0.035), the rates of total thymectomy were higher (P=0.028), and the pain scores on postoperative days 1, 3, and 7 were significantly lower (P<0.001, P<0.001, and P=0.03, respectively). A total of 112 patients with MG were followed up. The subxiphoid approach group reported higher rates of complete stable remission (CSR) and effective treatment of MG, although these differences were not statistically significant (Z=−0.484, P=0.627). By multivariate Cox proportional hazards modes analysis, the chance of CSR was significantly increased when age <40 (OR: 2.623, 95% CI: 1.150–5.983, P=0.022), non-thymomatous MG (OR: 1.078, 95% CI: 1.101–3.316, P=0.021) and MGFA clinical classification (OR: 2.024, 95%:1.164–3.523, P=0.013).

Conclusions

The subxiphoid approach has shorter operation time, higher rates of total thymectomy and better quality of life compared with the lateral thoracoscopic approach. Preoperative age, pathological diagnoses and MGFA Clinical Classification are the independent risk factors for non-complete stable remission (NCSR) after thymectomy.

Surgical Techniques for Myasthenia Gravis: Video-Assisted Thoracic Surgery

We describe the various video-assisted thoracic surgery approaches to the thymus currently adopted in nonthymomatous and thymomatous myasthenic patients. Despite several controversies, video-assisted thoracic surgery thymectomy gained worldwide popularity. Classic 3-port approaches proved safe and effective. Uniportal video-assisted thoracic surgery requires consolidated experience, whereas the bilateral approach is considered more extensive. Subxiphoid represents the ultimate and exciting challenge. As an effect of video-assisted thoracic surgery approach, thymectomy is performed earlier; both patients and neurologists are more prone to accept the procedure given the quicker recovery, lesser pain, and better cosmesis. Outcomes are equivalent to those achieved by sternotomy.

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.

A Phase II Study of Partial and Subtotal Thymectomy for Thymoma (JART02)

BACKGROUND

We believe the merit of preservation of a part of the thymus following surgery for thymoma. We evaluated the efficacy of partial or subtotal thymectomy for early-stage thymoma in the prospective study.

METHODS

The Japanese Association for Research on the Thymus conducted a multiple institutional study of thymectomy for thymoma localized in the thymus without total thymectomy. Patients without autoimmune disease who had an anterior mediastinal tumor that had been clinically diagnosed as an early-stage thymoma were enrolled in the study. Patients who were positive for anti-acetylcholine receptor antibodies were excluded.

RESULTS

Sixty-three patients were enrolled preoperatively; 27 patients were judged as being inappropriate based on the other thymic pathologies or tumor invasion. The remaining 36 cases were diagnosed as early-staged thymoma and analyzed. The mean age of the patients was 61 years. The mean maximal tumor diameter in the resected specimens was 3.6 cm. The most common pathological types of thymoma were AB (n = 10) and B1 (n = 10). The Masaoka stages were classified as stage I (n = 22) and II (n = 14). The mean observation period was 63 months. Two patients died due to respiratory dysfunction, which was not related to thymoma. One hundred percent of the patients remained recurrence-free.

CONCLUSIONS

This prospective study suggested the efficacy of partial or subtotal thymectomy for early-stage thymoma in patients without any apparent evidence of autoimmune disease. We can preserve a part of the thymus even following surgery for thymoma to prepare the possible second malignancies or diseases in future.

Thoracoscopic Thymectomy Using a Subxiphoid Approach for Anterior Mediastinal Tumors

PURPOSE

Video-assisted thoracic surgery (VATS) techniques have been widely used for resection of mediastinal tumors. This study investigated the usefulness of the subxiphoid approach in thoracoscopic thymectomy.

METHODS

In all, 36 patients with anterior mediastinal tumor underwent thymectomy using the subxiphoid approach in two Japanese institutions. These patients were retrospectively reviewed and analyzed.

RESULTS

There were 16 females and 20 males with a mean age of 57 years. Five patients underwent partial thymectomy (PT), 27 underwent total or subtotal thymectomy, and 4 underwent thymectomy with combined resection (CR) of the surrounding organs or tissues. The mean maximum tumor diameter, amount of resected tissue, and blood loss were 4.1 cm, 72.5 g, and 20.6 g, respectively. More than half of tumors were diagnosed as thymoma (n = 19). The operation time was prolonged with a greater volume of thymectomy. The duration of chest tube drainage and postoperative stay were 1.7 ± 1.0 days and 5.9 ± 7.6 days, respectively. Four patients suffered intraoperative and postoperative complications, as follows: bleeding of the innominate vein, bleeding of the internal thoracic vein, crisis of myasthenia gravis (MG), pericarditis, and phrenic nerve paralysis. There were no mortalities after surgery.

CONCLUSION

Subxiphoid thoracoscopic thymectomy might be a safe and useful approach for mediastinal tumors.

Subxiphoid uniportal VATS thymectomy

Background

To present the technique of minimally invasive extended thymectomy performed through the uniportal subxiphoid approach, with double elevation of the sternum for nonthymomatous myasthenia gravis (MG).

Methods

Operative technique: the whole dissection was performed through the 4-7 cm transverse or longitudinal subxiphoid incision with use of videothoracoscope. The sternum was elevated with two hooks connected to the sternal frame (Rochard bar, Aesculap-Chifa, Nowy Tomysl, Poland). The lower hook was inserted through the subxiphoid incision and the superior hook was inserted percutaneously, after the mediastinal tissue including the major mediastinal vessels were dissected from the inner surface of the sternum. The fatty tissue of the anterior mediastinum and the aorta-pulmonary window was completely removed.

Results

There were four patients in the period 1.1.2017-30.4.2017. There was no mortality and morbidity.

Conclusions

The uniportal subxiphoid approach combined with double elevation of the sternum enabled very extensive thymectomy in case of thymoma.

Minimally invasive surgical procedures for thymic disease in Asia

Video-assisted thoracic surgery (VATS) procedures for thymic tumors and myasthenia gravis were introduced in Asia in the middle 1990s in at least two regions, Hong Kong and Japan. To overcome difficulties in obtaining a wide view of the anterior mediastinum, several methods for lifting the sternum or anterior chest wall have been presented, mainly by Japanese surgeons. More recently, single port VATS through a subxiphoid incision was also introduced in Japan. The long-term outcome of a VATS extended thymectomy for myasthenia gravis has been shown to be comparable to that of a trans-sternal extended thymectomy, while the long-term outcome of a VATS thymectomy for thymic epithelial tumors remains to be elucidated. Nevertheless, its indication for tumors in an early stage is now widely accepted, and the number of VATS procedures is steadily increasing in Japan and China. Single-port VATS through a subxiphoid incision was developed in Japan and might become accepted as a useful approach in the near future when combined with robot-assisted thoracoscopic surgery. In addition, robot-assisted thoracoscopic surgery for the thymus has also been introduced in some areas in Asia. Although few of those surgical procedures for the thymus have been performed, results obtained thus far indicate that it might be preferable to lung resection. Several novel minimally invasive thymectomy techniques have been invented and developed in Asia, and further advancements in this field by Asian surgeons are anticipated.

Extended thymectomy by a cervical incision additional to bilateral VATS approach

BACKGROUND

Video-assisted thoracoscopic surgery (VATS) in thymectomy has shown safe and effective with many advantages in myasthenia gravis (MG) patients with or without thymoma than transsternal approach. This video aims to show the procedure of extended thymectomy via a cervical incision additional to bilateral VATS approach in a MG patient with an early stage thymoma.

METHODS

The patient was a 46-year-old male who had onset of symptoms of blurred vision, dysarthria and dysphagia for 10 months before administration. A diagnosis of MG was then confirmed using anticholinesterase test and electromyography test by neurologists. A CT scan showed enlarged thymus and a mass close to the left innominate vein in the anterior mediastinum with a size of 12 mm × 13 mm. Without any contradictions, the patient was planned to receive a procedure of extended thymectomy.

RESULTS

The patient recovered with no complications and was discharged on the 8th postoperative day. Histological pathology examination revealed a type B3 thymoma of Masaoka stage II.

CONCLUSIONS

Oncological principles and immunological considerations are equally important in surgery for the MG patients with thymoma. All the thymus gland in the mediastinum including ectopic thymic tissue in the cervical region should be removed in the procedure. In conclusion, we suggest this approach to be safe and feasible for thymoma surgery in patients with MG.

Intraoperative Near-Infrared Fluorescence Imaging of Thymus in Preclinical Models

BACKGROUND

There are currently no thymus-specific contrast agents for biomedical imaging. Thus, finding ectopic thymic tissue during certain operations is extremely difficult. The purpose of the present study was to determine if near-infrared (NIR) fluorescence imaging could provide high sensitivity, real-time identification of thymic tissue during the operation.

METHODS

After initial in vivo screening of a 315-compound NIR fluorophore library for thymic uptake, methylene blue and five different 700-nm emitting candidate molecules were injected into CD-1 mice for quantitation of the signal-to-background ratio as a function of kinetics and dosing. Results were confirmed in 35-kg Yorkshire pigs. Dual-channel NIR imaging was also performed using a variety of 800-nm emitting NIR fluorophores targeted to various tissues in the mediastinum and neck.

RESULTS

The compound Oxazine 170 demonstrated the highest signal-to-background ratio (≥3) for thymic tissue relative to mediastinal fat, heart, lung, muscle, thyroid gland, and parathyroid gland, with peak signal-to-background ratio occurring 4 h after 1 intravenous injection of a human equivalent dose of approximately 7 mg. Simultaneous dual-channel NIR imaging permitted unambiguous identification of the thymus from surrounding tissues, such as endocrine glands and lymph nodes.

CONCLUSIONS

In mouse and pig, NIR fluorescence imaging using Oxazine 170 permits high sensitivity, real-time identification of thymic tissue for surgical procedures requiring its resection or avoidance. The performance of Oxazine 170 for imaging human thymic tissue is currently not known.

Single port VATS mediastinal tumor resection: Taiwan experience

BACKGROUND

To present the technique of single-port video-assisted thoracoscopic mediastinal tumor resection, which includes limited thymectomy, extended thymectomy, cyst excision and posterior mediastinal tumor excision, and the early results of resection with the use of this technique.

METHODS

Forty patients with mediastinal tumors were treated with single-port thoracoscopic mediastinal resection at Chang Gung Memorial Hospital between April 2014 and September 2015. The surgical intervention was performed through the fourth or fifth intercostal space at the anterior axillary line. A 5 or 10 mm 30 degree video camera and working instruments were employed simultaneously at this incision site throughout the surgery.

RESULTS

Among the 40 cases included in the final analysis, 10 extended thymectomies, 7 limited thymectomies, nine cyst excisions and 14 tumor excisions were performed successfully without the need for conversion. For the 40 patients who underwent single-port video-assisted thoracoscopic surgery (VATS), the mean operation time was 97.3±31.2 min and the average blood loss was 29.75±39.77 mL. The average length of the incision wound was 3.22±0.79 cm and the average length of postoperative hospital stay was 3.72±1.63 days. There were no mortalities and mobility was achieved within 30 days postoperatively.

CONCLUSIONS

Our preliminary report suggests that uniportal VATS for mediastinal tumor resection is a promising and safe technique within a short-term period.

Single-port video-assisted thoracoscopic mediastinal tumour resection

OBJECTIVES

To present the technique of single-port video-assisted thoracoscopic mediastinal tumour resection, which includes limited thymectomy, extended thymectomy, cyst excision and posterior mediastinal tumour excision, and the early results of resection with the use of this technique.

METHODS

Twenty-nine patients with mediastinal tumours were treated with single-port thoracoscopic mediastinal resection at Chung Gung Memorial Hospital between April 2014 and May 2015.The surgical intervention was performed through the fourth or fifth intercostal space at the anterior axillary line. A 5- or 10-mm 30° video camera and working instruments were employed simultaneously at this incision site throughout the surgery. The perioperative variables and outcomes were collected and analysed retrospectively.

RESULTS

Among the 29 cases included in the final analysis, 8 extended thymectomies, 5 limited thymectomies, 7 cyst excisions and 9 tumour excisions were performed successfully without the need for conversion. For the 29 patients who underwent single-port video-assisted thoracoscopic surgery (VATS), the mean operation time was 97.3 ± 31.2 min and the average blood loss was 34.1 ± 45.7 ml. The average length of the incision wound was 3.41 ± 0.76 cm and the average length of postoperative hospital stay was 3.75 ± 1.53 days. There were no mortalities, and mobility was achieved 30 days after surgery.

CONCLUSIONS

With regard to oncological concerns, the occurrence of postoperative myasthenia gravis or freedom from tumour recurrence is a paramount issue. Our cohort follow-up time was not long enough to address this, and more time and patients are needed for further evaluation. But our preliminary report showed that uniportal VATS for mediastinal tumour resection was a promising and safe technique with regard to short-term clinical outcome.

Heterogeneity in thymic emigrants: implications for thymectomy and immunosenescence

The development of mature, antigen-inexperienced (naive) T cells begins in the thymus and continues after export into the periphery. Post-thymic maturation of naive T cells, in humans, coincides with the progressive loss of markers such as protein tyrosine kinase 7 (PTK7) and platelet endothelial cell adhesion molecule-1 (CD31). As a consequence, subpopulations of naive T cells can be recognised raising questions about the processes that give rise to the loss of these markers and their exact relationship to recent thymic emigrants (RTE). Here, we combine a mathematical survival analysis approach and data from healthy and thymectomised humans to understand the apparent persistence of populations of ‘veteran’ PTK7⁺T cells in thymectomised individuals. We show that a model of heterogeneity in rates of maturation, possibly linked to natural variation in TCR signalling thresholds or affinity for self-antigens, can explain the data. This model of maturation predicts that the average post-thymic age of PTK7⁺T cells will increase linearly with the age of the host suggesting that, despite the immature phenotype, PTK7⁺cells do not necessarily represent a population of RTE. Further, the model predicts an accelerated increase in the average post-thymic age of residual PTK7⁺T cells following thymectomy and may also explain in part the prematurely aged phenotype of the naive T cell pool in individuals thymectomised early in life.

Unilateral extended thoracoscopic thymectomy for nontumoral myasthenia gravis--a new standard

Myasthenia gravis (MG) is a heterogeneous disorder with a fluctuating, clinical, pathologic, and immunobiological picture. Today, it is believed that effective treatment of MG must include both immunosuppression and surgery. Thymectomy is recommended by neurologists for patients with nontumoral MG as an option to increase the probability of remission or improvement. Currently, thoracoscopic thymectomy is considered a good alternative to the standard open approach because of its higher rate of acceptance, low morbidity, and high efficacy, as measured by complete stable remission rates. We present a review of the experience of unilateral extended thoracoscopic thymectomy for nontumoral MG, a technique that could became a new standard in the complex management of MG treatment.

Single-institution experience on robot-assisted thoracoscopic operations for mediastinal diseases

OBJECTIVE

: After the introduction of video-assisted thoracoscopic surgery 20 years ago, the minimally invasive techniques in thoracic surgery have found a growing application. The recent introduction of robotic technology has increased the potentiality of thoracoscopic technique leading to an expansion of indications and applications, particularly for the management of mediastinal diseases. We reviewed our experience in robot-assisted thoracoscopic resection of benign and malignant mediastinal diseases.

METHODS

: Between 2002 and 2010, 108 patients (79 women and 29 men; median age 38 y) underwent robot-assisted thoracoscopy using the "da Vinci" robotic system for several mediastinal diseases. There were 100 thymectomies, 3 resections of paravertebral tumors, 1 thymic cyst, 1 ectopic goitre, 1 ectopic mediastinal parathyroidectomy, 1 thymic carcinoid, and 1 foregut cyst. Ninety-five (87.9%) patients were affected by myasthenia gravis.

RESULTS

: All procedures were completed successfully using the da Vinci robot; no open conversions were required, but in three (2.8%) cases, a fourth access was added. There was no surgical mortality; four (3.6%) patients had postoperative complications (two hemothorax, one chylothorax, and one fever) treated conservatively. Median operation time was 120 (range 60-300) minutes and median hospitalization was 3 (range 2-14) days. Global benefit rate for patients with myasthenia gravis reached the value of 93.4% with progressive improvement over years.

CONCLUSIONS

: Several mediastinal operations may be feasible by using a robot-aided thoracoscopic approach. The technical innovations offered by robotic instrumentation make all procedures safer and easier when compared with standard thoracoscopic approach, with particular reference for application in mediastinal field.

Minimally invasive subxiphoid-right, videothoracoscopic technique of thymectomy for thymoma and rethymectomy

Minimally invasive subxiphoid-right, videothoracoscopic (VATS) technique of thymectomy for thymoma is presented. This approach enables complete removal of the whole thymus, with visualization of the lower poles of the thyroid. The whole dissection is performed through the 4-7&emsp14;cm subxiphoid approach with single 5-mm port insertion into the right chest cavity for the thoracoscope and, subsequently for the chest tube. The sternum is elevated with two hooks connected to the sternal frame. The lower hook is inserted through the subxiphoid incision and the superior hook is inserted percutaneously after the mediastinal tissue including the major mediastinal vessels that are dissected from the inner surface of the sternum. Generally, the left mediastinal pleura is not opened. The fatty tissue of the perithymic, right pericardiophrenic and aorta-pulmonary window can be completely removed. The dissection of the lower neck, aorta-caval groove and the left pericardiophrenic areas are not as complete as in the previously reported transcervical-subxiphoid, -bilateral VATS maximal thymectomy, however, therefore, the subxiphoid-right VATS technique of thymectomy have been used for early stage thymomas, not for non-thymomatous Myasthenia gravis. In this article, some important steps facilitating safe and straightforward performance of the procedure are presented and the methods of management of intraoperative complications are discussed.

Single-incision surgery with SILS port for anterior mediastinal lesions: initial experience

Infrasternal mediastinoscopic single-incision surgery is a minimally invasive surgical option for patients with anterior mediastinal lesions. The main drawback of the procedure is difficult when handling the endoscopic instruments through the small infrasternal incision. Herein, we report our initial experience with use of the procedure in 2 patients with bronchogenic cysts in the anterior mediastinum. We found that use of an SILS Port, now widely available for single-incision laparoscopic surgery, can decrease the difficulty of this approach.

Management of myasthenic patients with thymoma

Myasthenia gravis (MG) associated with thymomas differs from nonthymomatous MG, and thymomas associated with MG are also different from non-MG thymomas. According to the World Health Organization classification, the incidence of MG in thymomas was the highest in the subtypes B2, B1, and AB. Transsternal approach is still regarded as the gold standard for surgical treatment of thymomas. Less-invasive techniques of thymectomy are promising, but it is too early to estimate their real oncological value. In the series including more than 100 patients, the prognosis for survival is better in patients with thymomas associated with MG than in those with non-MG thymomas, and the prognosis for patients with MG associated with thymoma is worse than that for patients with nonthymomatous MG.

Transcervical video-assisted thymectomy: preliminary results of a modified surgical approach

PURPOSE

A number of surgical approaches have been reported for thymectomy, including transsternal, transcervical, a combination of complete transsternal and transcervical, and various video-assisted thoracoscopic surgery techniques. A modified video-assisted transcervical approach to thymectomy is here described.

METHODS

A video-assisted total thymectomy was performed through a 30-mm cervical incision. No hyperextension of the patient's neck or sternal retractor was used. The surgical instruments utilized for the resection were the ones created for the minimally invasive video-assisted thyroidectomy.

RESULTS

Five patients have been operated on so far. The encapsulated gland was removed without any difficulties. No complications occurred. No pain relief was administered after the first 24 h. The patients were discharged within the first two postoperative days. An improvement in clinical symptoms was registered in all patients.

CONCLUSIONS

An advantage of this minimally invasive video-assisted transcervical approach to thymectomy is that the entire operation can be performed without neck hyperextension or permanent sternum elevation. Moreover, the surgical instruments created for minimally invasive video-assisted thyroidectomy enabled us to be very precise and to complete the resection without any postoperative morbidity.

Transsternal maximal thymectomy is effective for extirpation of cervical ectopic thymic tissue in the treatment of myasthenia gravis

PURPOSE

Extensive extirpation of cervico-mediastinal adipose tissue increases the chance of removing ectopic thymic tissues, thus potentially improving the prognosis of myasthenia gravis after thymectomy. We sought to increase efficacy and safety of transsternal maximal thymectomy (TSMT).

MATERIALS AND METHODS

Twenty four patients who underwent TSMT from July 2006 to June 2007 were retrospectively reviewed and compared with 73 patients who underwent transsternal extended thymectomy (TSET) from January 2004 to May 2006. Ectopic thymic tissue in additionally excised cervicomediastinal fat tissue was examined histologically.

RESULTS

In TSMT group, operation time, amount of cumulative drainage and duration of drainage were significantly higher than TSET group. However, the difference in hemoglobin count, amount of transfusion, duration of intensive care, postoperative hospital stay, and complication rates were not statistically different. There was no operative mortality in either group. Ectopic thymic tissue was found in 50% of patients. All patients had ectopic thymic tissues in the cervical area. Two patients had additional ectopic tissue in the aortopulmonary window, and 1 patient had ectopic tissue at posterior of the left bracheocephalic vein and lateral of the right phrenic nerve.

CONCLUSION

TSMT is more effective in the extirpation of ectopic thymic tissues than TSET without significant impairment of safety, especially in the cervical area.