Perioperative outcomes and long-term survival in clinically early-stage thymic malignancies: video-assisted thoracoscopic thymectomy versus open approaches

Long-term prognosis in patients with thymoma combined with myasthenia gravis: a propensity score-matching analysis

Introduction

We aimed to assess the impact of myasthenia gravis (MG) on the long-term prognosis in patients with thymoma after surgery and identify related prognostic factors or predictors.

Methods

This retrospective observational study included 509 patients with thymoma (thymoma combined with MG [MG group] and thymoma alone [non-MG group]). Propensity score matching was performed to obtain comparable subsets of 96 patients in each group. A comparative analysis was conducted on various parameters.

Results

Before matching, the 10-year survival and recurrence-free survival rates in both groups were 93.8 and 98.4%, and 85.9 and 93.4%, respectively, with no statistically significant difference observed in the survival curves between the groups (p > 0.05). After propensity score matching, 96 matched pairs of patients from both groups were created. The 10-year survival and recurrence-free survival rates in these matched pairs were 96.9 and 97.7%, and 86.9 and 91.1%, respectively, with no statistical significance in the survival curves between the groups (p > 0.05). Univariate analysis of patients with thymoma postoperatively revealed that the World Health Organization histopathological classification, Masaoka-Koga stage, Tumor Node Metastasis stage, resection status, and postoperative adjuvant therapy were potentially associated with tumor recurrence after thymoma surgery. Multivariate analysis demonstrated that the Masaoka-Koga stage and postoperative adjuvant therapy independently predicted the risk of recurrence in patients with thymoma after surgery.

Conclusion

There was no difference in prognosis in patients with thymoma with or without MG. The Masaoka-Koga stage has emerged as an independent prognostic factor affecting recurrence-free survival in patients with thymoma, while postoperative adjuvant therapy represents a poor prognostic factor.

Perioperative outcomes and survival of modified subxiphoid video-assisted thoracoscopic surgery thymectomy for T2-3 thymic malignancies: A retrospective comparison study

OBJECTIVE

Our previous study demonstrated that modified subxiphoid video-assisted thoracic surgery thymectomy with an auxiliary sternal retractor is feasible for locally invasive thymic malignancies. This study aimed to compare perioperative and oncological outcomes of modified subxiphoid video-assisted thoracoscopic surgery thymectomy versus median sternotomy thymectomy for locally advanced thymic malignancies.

METHODS

In total, 221 patients with T2-3 thymic malignancies who underwent modified subxiphoid video-assisted thoracoscopic surgery thymectomy or median sternotomy thymectomy between 2015 and 2020 were enrolled in our prospectively maintained database. A 1:1 propensity score-matching analysis was performed to balance the bias. Surgical difficulty was evaluated with a modified resection index. Perioperative and oncological results were compared between the modified subxiphoid video-assisted thoracoscopic surgery thymectomy group and the median sternotomy thymectomy group.

RESULTS

There were 72 patients in each group in the final analysis. Our results showed that the modified subxiphoid video-assisted thoracoscopic surgery thymectomy group had a shorter operative duration (98 vs 129 minutes, P < .001), less blood loss (40 vs 100 mL, P < .001), shorter drainage duration (3 vs 5 days, P < .001), shorter length of hospital stay (5 vs 6 days, P < .001), and fewer postoperative complications (5.6% vs 23.6%; P = .005). No significant difference was detected in complete resection (98.6% vs 98.6%, P = 1.000) between the 2 groups. Conversion occurred in 5 of 106 patients (4.7%). Survival analyses indicated similar recurrence-free survival (hazard ratio, 0.94; 95% CI, 0.40-2.20; P = .883) and overall survival (hazard ratio, 0.52; 95% CI, 0.05-5.02; P = .590) between the 2 groups.

CONCLUSIONS

Modified subxiphoid video-assisted thoracoscopic surgery thymectomy was safe and effective for T2-3 thymic malignancies and could be an alternative for selected patients with locally advanced thymic diseases. Further prospective studies are needed to evaluate the long-term survival of those undergoing modified subxiphoid approach thoracoscopic thymectomy.

China Anti-Cancer Association Guidelines for the diagnosis, treatment, and follow-up of thymic epithelial tumors (2023)

Background

Thymic epithelial tumors (TETs) are a relatively rare type of thoracic tumors with higher incidence in Asians. The diagnosis and treatment pattern has long been based mainly on clinical experience and expert consensus. In recent years, with an increasing number of TETs detected in physical examinations, there is an urgent need to develop the guidelines that apply to the Chinese population. Thus, we intend to develop a holistic integrative guideline for TETs.

Methods

Under the leadership of the Chinese Anti-Cancer Association (CACA) Mediastinal Tumor Committee, a multidisciplinary guideline development group was established. Systemic literature review and two rounds of questionnaires regarding key clinical issues were carried out. The grading of recommendations assessment, development and evaluation (GRADE) approach was used to rate the quality of evidence and the strength of recommendations.

Results

The CACA guideline provides recommendations for the clinical differential diagnosis of anterior mediastinal lesions, management of asymptomatic small anterior mediastinal nodules, pathological classification and staging systems of TETs, as well as principles of surgery, neoadjuvant and adjuvant therapies, systemic therapies for advanced TETs, and follow-up strategies after surgical resection.

Conclusions

This guideline provides holistic integrative management strategies for TETs and would be a useful tool for clinicians on decision-making.

A uniport subxiphoid approach with a modified sternum retractor is safe and feasible for anterior mediastinal tumors

Background

Minimally invasive surgery has been used to treat anterior mediastinal tumors. This study sought to describe a single team's experience of uniport subxiphoid mediastinal surgery using a modified sternum retractor.

Methods

Patients who underwent uniport subxiphoid video-assisted thoracoscopic surgery (USVATS) or unilateral video-assisted thoracoscopic surgery (LVATS) from September 2018 to December 2021 were retrospectively enrolled in this study. A 5-cm vertical incision approximately 1-cm caudal to the xiphoid process was usually made followed by the installment of a modified retractor, which was able to raise the sternum by 6-8 cm. Next, the USVATS was performed. In the unilateral group, 3 1-cm incisions were usually made, among which, 2 are made in the 2nd or 3rd and 5th intercostal anterior axillary line, and the 3rd was made in the 5th intercostal midclavicular line. In some instances, an additional subxiphoid incision was made to remove the large tumors. All the clinical and perioperative data, including the prospectively recorded visual analogue scale (VAS) score, were analyzed.

Results

In total, 16 patients who underwent USVATS and 28 patients who underwent LVATS were enrolled in this study. With the exception of tumor size (USVATS 7.9±1.6 cm vs. LVATS 5.1±2.4 cm, P<0.001), the baseline data of the patients in the 2 groups were comparative. Blood loss in surgery, conversion, draining duration, postoperative stay, postoperative complications, pathology and tumor invasion were similar between the 2 groups. Although the operation time was significantly longer in the USVATS group than the LVATS group (115±19 vs. 83±30 min, P<0.001), the VAS score at 1st postoperative day (1.9±1.1 vs. 3.1±1.1, P<0.001) and moderate pain level (a VAS score >3) (6.3% vs. 32.1%, P=0.049) were better in the USVATS group than the LVATS group.

Conclusions

Uniport subxiphoid mediastinal surgery is a feasible and safe procedure, especially for large tumors. Our modified sternum retractor is especially helpful during uniport subxiphoid surgery. Compared to lateral thoracic surgery, this approach has the advantages of less injury and lower postoperative pain, which may lead to a faster recovery. However, its long-term follow-up outcomes need to be observed.

Prognostic CT features in patients with untreated thymic epithelial tumors

To determine the prognostic CT features in patients with untreated thymic epithelial tumors (TETs). Clinical data and CT imaging features of 194 patients with pathologically confirmed TETs were retrospectively reviewed. The subjects included 113 male and 81 female patients between 15 and 78 years of age, with a mean age of 53.8 years. Clinical outcomes were categorized according to whether relapse, metastasis or death occurred within 3 years after the first diagnosis. Associations between clinical outcomes and CT imaging features were determined using univariate and multivariate logistic regression analyses, while the survival status was analyzed by Cox regression. In this study, we analyzed 110 thymic carcinomas, 52 high-risk thymomas and 32 low-risk thymomas. Percentages of poor outcome and patient death in thymic carcinomas were much higher than those in patients with high-risk and low-risk thymomas. In the thymic carcinomas groups, 46 patients (41.8%) experienced tumor progression, local relapse or metastasis and were categorized as having poor outcomes; vessel invasion and pericardial mass were confirmed to be independent predictors by logistic regression analysis (p < 0.01). In the high-risk thymoma group, 11 patients (21.2%) were categorized as having poor outcomes, and the CT feature pericardial mass was confirmed to be an independent predictor (p < 0.01). In survival analysis, Cox regression showed that CT features of lung invasion, great vessel invasion, lung metastasis and distant organ metastasis were independent predictors for worse survival in the thymic carcinoma group (p < 0.01), while lung invasion and pericardial mass were independent predictors for worse survival in high-risk thymoma group. No CT features were related to poor outcome and worse survival in the low-risk thymoma group. Patients with thymic carcinoma had poorer prognosis and worse survival than those with high-risk or low-risk thymoma. CT can serve as an important tool for predicting the prognosis and survival of patients with TETs. In this cohort, CT features of vessel invasion and pericardial mass were related to poorer outcomes in those with thymic carcinoma and pericardial mass in those with high-risk thymoma. Features including lung invasion, great vessel invasion, lung metastasis and distant organ metastasis indicate worse survival in thymic carcinoma, whereas lung invasion and pericardial mass indicate worse survival in high-risk thymoma.

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.

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.

[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.

Limited resection for early-stage thymoma: minimally invasive resection does not mean limited resection

Standard resection for patients with thymoma is resection of thymoma with total thymectomy (TTx) via median sternotomy. Hence, limited resection for thymoma means a lesser extent of resection of normal thymus compared with a standard procedure, i.e. resection of thymoma with partial thymectomy (PTx). In contrast, minimally invasive resection has been defined as resection of thymoma with TTx via a less-invasive approach. However, to date, few studies have precisely evaluated the differences in surgical and oncological outcomes among these three procedures. This report summarizes the differences among these three procedures with a review of studies (January 2000 to December 2020) focusing on the difference in surgical and oncological outcomes and presents current issues in the surgical management of thymoma. In this report, 16 studies were identified; 5 compared standard resection to limited resection, 9 compared standard resection to minimally invasive resection and 2 compared limited resection to minimally invasive resection. Most studies reported that the surgical and oncological outcomes of limited resection or minimally invasive resection were similar to those of standard resection in patients with early-stage thymoma. However, they did not include a sufficient follow-up period. Both limited resection and minimally invasive resection for early-stage thymoma might be reasonable treatment options. However, they are still promising modes of resection. Further studies with a long follow-up period are needed.

The Early Perioperative Outcomes of Subxiphoid Approach Versus Lateral Intercostal Approach Thoracoscopic Thymectomy for Thymic Tumors: A Meta-Analysis

Objectives: To systematically evaluate the early perioperative outcomes regarding the safety and efficacy of subxiphoid thoracoscopic thymectomy (STT) versus lateral intercostal thoracoscopic thymectomy (LITT) for patients with thymic tumors. Methods: A thorough literature search of the following online databases was performed: Web of Science, PubMed, Embase, Cochrane Library, Google Scholar, and ClinicalTrials.gov. Original research articles published before December 30, 2020, that compared STT with LITT were included. Meta-analysis was performed for early perioperative outcomes, including blood loss, pain score, duration of hospital stay, operative time, chest tube drainage time, and incidence of postoperative complications. Results: Six studies that included 604 patients were finally selected for our analysis, with 296 cases of STT and 308 cases of LITT. Our results showed that compared with LITT, STT was associated with less blood loss (standardized mean difference = -0.81, 95% confidence interval [CI] = -1.49 to -0.14, P = .02), a lower pain score (weighted mean difference [WMD] = -2.55, 95% CI = -3.52 to -1.59; P < .00001), and a shorter hospital stay (WMD = -1.37, 95% CI = -2.37 to -0.36; P = .008), whereas there were no significant differences with regard to the operative time (WMD = -10.04, 95% CI = -22.29 to 2.21, P = .11), chest tube drainage time (WMD = -0.58, 95% CI = -1.17 to 0.02, P = .06), and the incidence of postoperative complications (odds ratio = 0.75, 95% CI = 0.39 to 1.44, P = .38). Conclusions: The current analysis suggests that STT is superior to LITT with respect to the early perioperative outcomes, and STT is a safe and effective surgical method for patients with thymic tumors.

Report from the European Society of Thoracic Surgeons prospective thymic database 2017: a powerful resource for a collaborative global effort to manage thymic tumours

OBJECTIVES

We queried the European Society of Thoracic Surgeons (ESTS) prospective thymic database for descriptive analysis and for comparison with the ESTS retrospective thymic database (1990-2010).

METHODS

Data were retrieved (January 2007-November 2017) for 1122 patients from 75 ESTS institutions.

RESULTS

There were 484 (65%) thymomas, 207 (28%) thymic carcinomas and 49 (7%) neuroendocrine thymic tumours. Staging (Masaoka) included 483 (67%) stage I and II, 100 (14%) stage III and 70 (10%) stage IV tumours. The new International Association for the Study of Lung Cancer/International Thymic Malignancies Interest Group tumour, node and metastasis (TNM) classification was available for 224 patients and including 177 (85%) stage I-II, 37 (16%) stage IIIA and 10 (4%) stage IIIB tumours. Chemotherapy as induction and adjuvant treatment was used in 14% and 15% of the patients. Radiotherapy was almost exclusively used postoperatively (24%). A minimally invasive surgical approach (video-assisted thoracic surgery/robotic-assisted thoracic surgery) was used in 276 (33%) patients. The overall recurrence rate was 10.8% (N = 38). Compared to the ESTS retrospective database, the increased prevalence of thymic carcinomas (from 9% to 28%) and neuroendocrine thymic tumours (from 2% to 7%), an increase in the use of minimally invasive techniques (from 6% to 34%) and a wider use of chemotherapy as induction (from 9% to 15%) and adjuvant (from 2% to 16%) treatment were observed in the prospective database. The introduction of a set of variables considered essential for the data use ('minimum dataset') resulted in an increased average completeness rate.

CONCLUSIONS

The reported data from the ESTS prospective thymic database confirm the recent trends in the management of thymic tumours. The ESTS prospective thymic database represents a powerful resource open to all ESTS members for the global effort to manage these rare tumours.

Minimal Access Surgery for Thymoma

Thymoma is a rare epithelial tumor of the thymus gland. Despite rarity, it is the most common tumor of the anterior mediastinum. Surgical resection in the form of extended thymectomy is the gold standard operation. Conventionally and even in the current era of significant advances in the minimally invasive surgery, open transsternal extended thymectomy is considered the gold standard, particularly for advanced-stage tumors. There is however significant evidence now available for the use of minimally invasive approaches for early-stage thymomas. This article aims to discuss the various minimally invasive approaches currently being employed for thymomas.

A national analysis of open versus minimally invasive thymectomy for stage I to III thymoma

OBJECTIVE

The oncologic efficacy of minimally invasive thymectomy for thymoma is not well characterized. We compared short-term outcomes and overall survival between open and minimally invasive (video-assisted thoracoscopic and robotic) approaches using the National Cancer Data Base.

METHODS

Perioperative outcomes and survival of patients who underwent open versus minimally invasive thymectomy for clinical stage I to III thymoma from 2010 to 2014 in the National Cancer Data Base were evaluated using multivariable Cox proportional hazards modeling and propensity score-matched analysis. Predictors of minimally invasive use were evaluated using multivariable logistic regression. Outcomes of surgical approach were evaluated using an intent-to-treat analysis.

RESULTS

Of the 1223 thymectomies that were evaluated, 317 (26%) were performed minimally invasively (141 video-assisted thoracoscopic and 176 robotic). The minimally invasive group had a shorter median length of stay when compared with the open group (3 [2-4] days vs 4 [3-6] days, P < .001). In a propensity score-matched analysis of 185 open and 185 minimally invasive (video-assisted thoracoscopic + robotic) thymectomy, the minimally invasive group continued to have a shorter median length of stay (3 vs 4 days, P < .01) but did not have significant differences in margin positivity (P = .84), 30-day readmission (P = .28), 30-day mortality (P = .60), and 5-year survival (89.4% vs 81.6%, P = .20) when compared with the open group.

CONCLUSIONS

In this national analysis, minimally invasive thymectomy was associated with shorter length of stay and was not associated with increased margin positivity, perioperative mortality, 30-day readmission rate, or reduced overall survival when compared with open thymectomy.

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.

Optimal management of thymic malignancies: current perspectives

Thymic epithelial tumors (TETs) belong to orphan oncology. The incidence of TETs is about 1.3–3.2 cases per million worldwide. Following pathology, evolution and prognosis are variable. The World Health Organization classification distinguishes thymomas and thymic carcinomas. TETs are composed of thymic epithelial tumoral cells and normal lymphocytes. The mean age at diagnosis is 50–60 years-old. There are no identified risk factors. TETs are frequently associated with paraneoplastic syndromes as myasthenia gravis. The complete R₀ surgical resection is the most significant prognosis factor on survival. In 2010, the French National Institute of Cancer labeled the RYTHMIC network as a specific tumor board including thoracic surgeons, oncologist, and radiation therapist to define standard of care for the management of TETs. The aim of the review was to update knowledge to optimize the standard of care.

Thoracoscopic thymectomy with partial superior vena cava resection for locally advanced thymomas

Background

Video-assisted thoracoscopic surgery (VATS) is now increasingly used for the treatment of early stage thymic malignancies. However, VATS has not been advocated for patients with locally advanced diseases. We reviewed our initial experience in VATS thymectomy with partial superior vena cava (SVC) resection for IASLC/ITMIG stage III thymic tumors.

Methods

From August 2017 to October 2018, patients who underwent VATS thymectomy with partial SVC resection were retrospectively reviewed, and peri-operative outcomes and short-term follow-up results were analyzing.

Results

Four patients with partial SVC resection via VATS were identified. All of them had pathologically confirmed IASLC/ITMIG stage III thymic tumors invading the SVC. The average of operative time was 228 minutes and mean blood loss was 88 mL. The mean duration of chest tube drainage and post-operative hospital stay were 4.5 and 7.3 days respectively. No major complication was encountered after surgery. No mortality was observed. And no recurrence was detected with the longest follow-up time of 14 months.

Conclusions

With careful patient selection and plenty surgical expertise, VATS thymectomy for locally invasive thymic tumors with limited the SVC invasion is challenging yet technically feasible.

Minimally invasive surgery in thymic malignances: the new standard of care

Surgery is the most important therapy for thymic malignancies. The last decade has seen increasing adoption of minimally invasive thymectomy (MIT) for thymic tumors. MIT for early stage diseases has been shown to yield similar oncological results while being helpful in minimizing surgical trauma, improving postoperative recovery, and reducing incisional pain. Similar surgical and oncological principles should be observed in both minimally invasive and open procedures so as to ensure radical resection and accurate staging of the tumor.

[Minimally Invasive Surgery in Thymic Malignances]

手术是胸腺肿瘤最重要的治疗方式。近年来，胸腺肿瘤的微创手术在国内外获得迅速推广。微创手术目前主要用于早期胸腺肿瘤的外科治疗，已有证据表明，微创手术可有效减少手术创伤、有效加快患者的术后恢复以及降低术后疼痛，并且目前已有一定临床证据初步证实其肿瘤学效果与开放手术相当。同时随着外科技术的不断进步，在保证外科学和肿瘤学原则的前提下，微创手术有可能使包括局部进展期、诱导治疗后以及复发转移的患者从中获益。

Minimally invasive techniques in thymic surgery: a worldwide perspective

Minimally invasive surgical techniques are important in surgical management of thymic pathologies. Traditional access techniques are being replaced with minimally invasive techniques using multiportal or uniportal approach. Adoption of minimally invasive techniques for thymic malignancies has been slow due to long term recurrence concerns. Recent studies show that minimally invasive video-assisted thoracoscopic surgery (VATS) or robotic approach to early stage thymic malignancies are associated with less intraoperative bleeding, lower rate of respiratory complications, shorter chest tube duration and shorter hospital stay. Oncologic outcomes are at least equivalent to open approach. Minimally invasive approach for benign pathologies is widely applied. There are significant variations in VATS approaches for thymus, showing a multinational interest in the issue of minimizing trauma during thymectomy. Use of robotic technology is also popular, as the retrosternal area is a narrow anatomic space to manipulate conventional instruments. The evolution of minimally invasive surgery for thymus has been possible with contribution from centers all around the world. In the current practice, various approaches are being adopted and every surgeon should prefer a technique depending on surgical preference and experience.

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.