Video-assisted and minimally-invasive open chest surgery for the treatment of mediastinal tumors and masses

Surgical treatment of thymic epithelial tumors: a narrative review

Background and Objective

Thymic epithelial tumors (TETs) are scarce neoplasms of the prevascular mediastinum. Included in this diverse category of lesions are thymomas and thymic carcinomas (TCs). Surgery is the mainstay of treatment of tumors that are deemed resectable. However, up till now, optimal surgical access has been a subject of debate. The advent of new techniques, such as video-assisted thoracoscopic surgery (VATS) and robotic-assisted thoracoscopic surgery (RATS), challenged the median sternotomy which was traditionally considered the access of choice. This review aims to demonstrate the current evidence concerning the surgical treatment of TET and to enlighten other controversial issues about surgery.

Methods

PubMed research was conducted using the terms [surgery] AND [thymic epithelial tumors] OR [thymomas] and [surgical treatment] AND [thymic epithelial tumors] OR [thymomas]. Papers concerning pediatric cases and non-English literature papers were excluded. Individual case reports were also excluded.

Key Content and Findings

Minimally invasive surgical techniques (MIST) such as VATS and RATS are increasingly applied in early-stage TET. Although numerous published studies have demonstrated better perioperative outcomes in early-stage TET, long-term follow-up data are still required to demonstrate the oncological equivalent of MIST to open surgery. Resection of stage III TET is more challenging. Thymectomy can be expanded en bloc to include the major vascular structures, lung, pleura, phrenic, or vagus nerve in these individuals. There is no agreement on the ideal surgical access and traditionally these patients underwent open sternotomy, sometimes combined with a thoracic access. Evidence concerning the treatment of stage IVA disease is mainly derived from retrospective case series which are highly heterogeneous in terms of the number of enrolled patients, histology, degree of pleural involvement, and timing of presentation.

Conclusions

New techniques in the field of minimally invasive surgery are gaining acceptance for early-stage TET but longer follow-up periods are warranted to prove their oncological outcomes. On the contrary, these techniques should be used cautiously in case of locally advanced tumors. Surgeons must not forget that the main objective is the complete resection of the lesion, which is one major predictive factor for increased survival.

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

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

Mediastinal Parathyroid Cancer

Parathyroid cancer (PC) is rare, but its pre-operative recognition is important to choose appropriate access strategies and achieve oncological clearance. This study characterizes features of mediastinal parathyroid cancer (MPC) and explores criteria aiding in the pre-operative recognition of malignancy. We assembled data from 502 patients with mediastinal parathyroid neoplasms (MPNs) from a systematic review of the literature 1968−2020 (n = 467) and our own patient cohort (n = 35). Thirty-two of the 502 MPNs (6.4%) exhibited malignancy. Only 23% of MPC patients underwent oncological surgery. Local persistence and early recurrence at a median delay of 24 months were frequent (45.8%), and associated with a 21.7-fold (95%CI 1.3−351.4; p = 0.03) higher risk of death due to disease. MPCs (n = 30) were significantly larger than cervical PC (n = 330), at 54 ± 36 mm vs. 35 ± 18 mm (χ2 = 20; p < 0.0001), and larger than mediastinal parathyroid adenomas (MPA; n = 226) at 22 ± 15 mm (χ2 = 33; p < 0.01). MPC occurred more commonly in males (60%; p < 0.01), with higher calcium (p < 0.01) and parathyroid hormone (PTH) levels (p < 0.01) than MPA. Mediastinal lesions larger than 3.0 cm and associated with a corrected calcium ≥ 3.0 mM are associated with a more than 100-fold higher odds ratio of being malignant (OR 109.2; 95%CI 1.1−346; p < 0.05). The composite 3 + 3 criterion recognized 74% of all MPC with an accuracy of 83%. Inversely, no MPN presenting with a calcium < 3.0 mM and size < 3.0 cm was malignant. When faced with pHPT in mediastinal location, consideration of the 3 + 3 rule may trigger an oncological team approach based on simple, available criteria.

A single-center study of thoracoscopic surgery in the treatment of pediatric mediastinal neurogenic tumors

OBJECTIVE

To study the feasibility, safety, and efficacy of thoracoscopic surgery in the treatment of pediatric mediastinal neurogenic tumors, and summarize the treatment experiences and surgical skills.

METHODS

A single-center retrospective analysis of 37 patients with pediatric mediastinal neurogenic tumors was conducted. Clinical charactersistics and postoperative complications were all analyzed.

RESULTS

All the operations were successfully completed. There was no statistically significant difference in tumor diameter between the two groups (p > 0.05). The open surgery group had an average operation time of 96.5 ± 32.38 min, while the thoracoscopic surgery group had an average operation time of 78.3 ± 24.51 min (p < 0.05). The thoracoscopic surgery group had significantly lower intraoperative blood loss than the open surgery group (p < 0.05). In addition, the duration of the postoperative thoracic drainage tube was 5.43 ± 0.76 days in the open surgery group, which was longer than the 2.38 ± 0.87 days in the thoracoscopic surgery group (p < 0.05). Furthermore, the postoperative length of hospital stay was an average of 10.23 ± 1.43 days for the open surgery group, longer than for the thoracoscopic surgery group (4.36 ± 0.87 days) (p < 0.05).

CONCLUSIONS

Thoracoscopic surgery has several advantages in the treatment of pediatric mediastinal neurogenic tumors and is worthy of clinical popularization and application. For giant mediastinal malignant neurogenic tumors, puncture biopsy and adjuvant chemotherapy can be performed before surgery to lessen the tumor volume and enlarge the operation space, which would reduce bleeding and complications.

The Role of Endoscopic Ultrasound in the Interventional Management of Mediastinal Collections: A Narrative Review

The numerous causes underlying mediastinal lesions require different diagnostic and therapeutic approaches, including conservative, minimally invasive, and surgical interventions. Solid lesions of a malignant nature, mostly located in the anterior mediastinum, are properly treated with surgical resection either with or without adjuvant schemes. In contrast, a surveillance program is usually recommended with solid benign tumors, depending on their size and related symptomatology. In the management of mediastinal collections, when a drainage intervention is required (suspicion of infection and symptomatology), a minimally invasive nonsurgical procedure or thoracic surgery is considered. The minimally invasive nonsurgical procedures that can be available are percutaneous radiology-guided imaging (abdominal ultrasound (US) or computed tomography (CT) scan), complete single-aspiration guided by endoscopic ultrasound (EUS) or endobronchial ultrasound (EBUS), and transmural drainage guided by EUS. Surgical debridement is feasible to treat collections, but as this entails considerable risk of postoperative complications, it is chosen only when other minimally invasive therapies are not possible. The published literature related to the interventional endoscopic approach to mediastinal lesions is scarce. Nevertheless, reports in this field reveal that interventional EUS may have a role in both the diagnosis of and therapeutic approach to mediastinal lesions, mainly in the management of mediastinal collections.

Safety of subxiphoid uniportal video-assisted thoracoscopic surgery for anterior mediastinal tumour in obese patients

Introduction

Subxiphoid uniportal video-assisted thoracoscopic surgery (VATS) has been gradually applied for the treatment of anterior mediastinal tumour (AMT). However, whether obesity is a risk factor for subxiphoid uniportal VATS for AMT is still unknown.

Aim

To explore the safety and short-term outcome of subxiphoid uniportal VATS for AMT in obese patients.

Material and methods

The clinical data of 142 patients who received VATS via subxiphoid approach for AMT were analysed. According to body mass index (BMI), the patients were divided into an obese group (BMI ≥ 28 kg/m²) and a non-obese group (BMI < 28 kg/m²). Then, the clinical and surgical characteristics between the obese group and the non-obese group were analysed to explore the effect of obesity on VATS for AMT. The pain scores were evaluated by the Numeric Rating Scale.

Results

The operative time and tracheal intubation time using subxiphoid uniportal VATS for AMT in the obese group were longer than that in the non-obese group (p < 0.05). However, there was no obvious difference in intraoperative blood loss, chest tube drainage time, chest tube drainage volume, and length of hospital stay between the obese group and the non-obese group (p > 0.05). Moreover, there was also no significant difference in postoperative complications, including pulmonary complications, wound infection, arrhythmia, and pulmonary leak, between the obese group and the non-obese group. In addition, the pain scores in the obese group were similar to those in the non-obese group.

Conclusions

Although obesity might prolong operative time of subxiphoid uniportal VAST for AMT, it does not increase the rate of postoperative complications. An experienced centre can properly conduct VAST via subxiphoid approach when treating AMT in obese patients.

Is single-port video-assisted thoracic surgery for mediastinal cystectomy feasible?

Background

Video-assisted thoracic surgery (VATS) for mediastinal cysts has been used with increasing frequency. Both single-port VATS and three-port VATS procedures are used for mediastinal cystectomy. Few studies have been published to compare three-port VATS and single-port VATS procedures in mediastinal cystectomy.

Methods

Forty-five patients with mediastinal cysts who underwent single-port procedures (n = 23) or three-port procedures (n = 22) in our department from January 2016 to July 2018 were retrospectively analysed. The perioperative conditions and pathological findings were analysed.

Results

The single-port group showed shorter operation times [45 (35–60) vs 55 (45–80) min, p = 0.013], less retention time of the thoracic drainage tube [27(24–48) vs 48(48–70) p < 0.001)], shorter postoperative hospital stays [5(4–6) vs 7(5–7), p = 0.011] and less costs [2.0)1.2–2.5) vs 2.5(1.9–3.5), p = 0.032] than those of the three-port group. No difference was found in case conversions to open procedures (p > 0.99) or second operations (p > 0.99). Logistic regression analysis showed that the surgical method (p = 0.426) and surgeon experience (p = 0.719) were not independent prognostic factors for the success of surgery.

Conclusions

The single-port VATS procedure was not inferior to the three-port VATS procedure for mediastinal cystectomy. The single-port VATS procedure is a feasible choice for mediastinal cystectomy.