Surgical mediastinal lymph node staging for non-small-cell lung carcinoma

Background

The current preferred approach for surgical mediastinal staging of non-small-cell lung carcinoma is video-assisted mediastinoscopy. An alternative technique in which lymph nodes are resected instead of biopsied is video-assisted mediastinoscopic lymphadenectomy (VAMLA) that is suggested to be superior in detecting N2 disease. Yet, evidence is conflicting and furthermore limited by sample size. The objective was to compare mediastinal staging through VAMLA and video-assisted mediastinoscopy.

Methods

A single-center cohort study was conducted. All consecutive patients that underwent surgical mediastinal staging of non-small-cell lung carcinoma by VAMLA (2011 to 2018) were compared to historic video-assisted mediastinoscopy controls (2007 to 2011). Patients with negative surgical mediastinal staging underwent subsequent anatomical resection with systematic regional lymphadenectomy. Primary outcome was the sensitivity and negative predictive value for detecting N2 disease.

Results

Two-hundred-sixty-nine video-assisted mediastinoscopic lymphadenectomies and 118 video-assisted mediastinoscopies were performed. The prevalence of N2 disease was 20% and 26% respectively in the VAMLA and video-assisted mediastinoscopy group, while the rate of unforeseen pN2 resulting from lymph node dissection during anatomical resection was 4% and 11%, respectively. Invasive staging using VAMLA demonstrated superior sensitivity of 0.82 and a negative predictive value of 0.96 when compared to video-assisted mediastinoscopy (0.62 and 0.89, respectively), offering a 64% decrease in risk of unforeseen pN2 following anatomical resection. However, VAMLA is also associated with a 75% risk increase on complications (P=0.36).

Conclusions

We conclude that performing invasive mediastinal lymph node assessment for staging of non-small-cell lung carcinoma, VAMLA should be the preferred technique with superior sensitivity and negative predictive value in detecting N2 disease. Though, VAMLA is also associated with an increased risk of complications.

The role of mediastinoscopy in the diagnosis of non-lung cancer diseases

BACKGROUND

Mediastinoscopy is a good method to evaluate mediastinal lesions. We sought to determine the current role of mediastinoscopy in the investigation of non-lung cancer patients with mediastinal lymphadenopathy.

MATERIALS AND METHODS

We retrospectively reviewed clinical parameters (age, gender, histological diagnosis, morbidity, mortality) of all patients without lung cancer who consecutively underwent mediastinoscopy in Hospital of Faculty of Medicine of Dicle University between June 2003 and December 2016.

RESULTS

Two-hundred twenty nine patients without lung cancer who underwent mediastinoscopy for the pathological evaluation of mediastinum during the study period were included. There were 156 female (68%) and 73 male (32%) patients. Mean age was 52.6 years (range, 16 to 85 years). Mean operative time was 41 minutes (range, 25 to 90 minutes). Mean number of biopsies was 9.3 (range, 5 to 24). Totally, 45 patients (19.6%) had previously undergone a nondiagnostic bronchoscopic biopsy such as transbronchial needle aspiration or endobronchial ultrasound-guided transbronchial needle aspiration. Mediastinoscopy was diagnostic for all patients. Diagnosis included sarcoidosis (n=100), tuberculous lymphadenitis (n=66), anthracosis lymphadenitis (n=44), lymphoma (n=11) metastatic carcinoma (n=5), and Castleman's disease (n=1); there was a diagnosis of silicosis in one patient and tymoma in one patient. Neither operative mortality nor major complication developed. The only minor complication was wound infection which was detected in three patients.

CONCLUSION

Although newer diagnostic modalities are being increasingly used to diagnose mediastinal diseases, mediastinoscopy continues to be a reliable method for the investigation of mediastinal lesions.

Surgical treatment of non-malignant laryngotracheal stenosis

The objectives of this study were the following: (1) to analyze the results of surgical treatment of non-malignant subglottic laryngeal and tracheal stenosis, (2) to evaluate the feasibility and technical aspects of the video mediastinoscopy for the mobilization of the mediastinal trachea, (3) to evaluate the influence of the early internal condition of the anastomosis on the development of restenosis. From 1996 up to 2013, 75 patients aged 11-78 years underwent surgery for post-intubation/tracheostomy (71 patients), post-traumatic (3 patients), and idiopathic (1 patient) subglottic laryngeal and tracheal stenosis. Twenty-three (30.7 %) patients with subglottic laryngeal and upper tracheal stenosis underwent cricotracheal resection and thyrotracheal anastomosis (group A), while 52 (69.3 %) patients with tracheal stenosis underwent tracheal resection and cricotracheal or tracheotracheal anastomosis (group B). The length of the resected segment in patients of groups A and B was 28-55 (42 ± 11) mm and 18-65 (36 ± 14) mm, respectively, (p = 0.22). Perioperative complications within 30 days occurred in eight (34.8 %) patients of group A, and in six (11.5 %) patients of group B (p = 0.04). There was one intraoperative and one postoperative death on the third day due to heart failure. The excellent results were achieved in 63 (86.3 %), satisfactory in 8 (11.0 %), and unsatisfactory in 2 (2.7 %) patients. The incidence rate of perioperative complications is related to the location of the stenosis and the type of the resection and anastomosis. Video mediastinoscopy simplifies the mobilization of the mediastinal trachea, which allows for carrying out the anastomosis with minimal tension. Early internal abnormalities of the anastomosis predict its restenosis.

Revised ESTS guidelines for preoperative mediastinal lymph node staging for non-small-cell lung cancer

Accurate preoperative staging and restaging of mediastinal lymph nodes in patients with potentially resectable non-small-cell lung cancer (NSCLC) is of paramount importance. In 2007, the European Society of Thoracic Surgeons (ESTS) published an algorithm on preoperative mediastinal staging integrating imaging, endoscopic and surgical techniques. In 2009, the International Association for the Study of Lung Cancer (IASLC) introduced a new lymph node map. Some changes in this map have an important impact on mediastinal staging. Moreover, more evidence of the different mediastinal staging technique has become available. Therefore, a revision of the ESTS guidelines was needed. In case of computed tomography (CT)-enlarged or positron emission tomography (PET)-positive mediastinal lymph nodes, tissue confirmation is indicated. Endosonography [endobronchial ultrasonography (EBUS)/esophageal ultrasonography (EUS)] with fine-needle aspiration (FNA) is the first choice (when available), since it is minimally invasive and has a high sensitivity to rule in mediastinal nodal disease. If negative, surgical staging with nodal dissection or biopsy is indicated. Video-assisted mediastinoscopy is preferred to mediastinoscopy. The combined use of endoscopic staging and surgical staging results in the highest accuracy. When there are no enlarged lymph nodes on CT and when there is no uptake in lymph nodes on PET or PET-CT, direct surgical resection with systematic nodal dissection is indicated for tumours ≤ 3 cm located in the outer third of the lung. In central tumours or N1 nodes, preoperative mediastinal staging is indicated. The choice between endoscopic staging with EBUS/EUS and FNA or video-assisted mediastinoscopy depends on local expertise to adhere to minimal requirements for staging. For tumours >3 cm, preoperative mediastinal staging is advised, mainly in adenocarcinoma with high standardized uptake value. For restaging, invasive techniques providing histological information are advisable. Both endoscopic techniques and surgical procedures are available, but their negative predictive value is lower compared with the results obtained in baseline staging. An integrated strategy using endoscopic staging techniques to prove mediastinal nodal disease and mediastinoscopy to assess nodal response after induction therapy needs further study.

Learning mediastinoscopy: the need for education, experience and modern techniques--interdependency of the applied technique and surgeon's training level

OBJECTIVES

Mediastinoscopy represents the gold standard for invasive mediastinal staging. While learning and teaching the surgical technique are challenging due to the limited accessibility of the operation field, both benefited from the implementation of video-assisted techniques. However, it has not been established yet whether video-assisted mediastinoscopy improves the mediastinal staging in itself.

METHODS

Retrospective single-centre cohort analysis of 657 mediastinoscopies performed at a specialized tertiary care thoracic surgery unit from 1994 to 2006. The number of specimens obtained per procedure and per lymph node station (2, 4, 7, 8 for mediastinoscopy and 2-9 for open lymphadenectomy), the number of lymph node stations examined, sensitivity and negative predictive value with a focus on the technique employed (video-assisted vs standard technique) and the surgeon's experience were calculated.

RESULTS

Overall sensitivity was 60%, accuracy was 90% and negative predictive value 88%. With the conventional technique, experience alone improved sensitivity from 49 to 57% and it was predominant at the paratracheal right region (from 62 to 82%). But with the video-assisted technique, experienced surgeons rose sensitivity from 57 to 79% in contrast to inexperienced surgeons who lowered sensitivity from 49 to 33%. We found significant differences concerning (i) the total number of specimens taken, (ii) the amount of lymph node stations examined, (iii) the number of specimens taken per lymph node station and (iv) true positive mediastinoscopies.

CONCLUSIONS

The video-assisted technique can significantly improve the results of mediastinoscopy. A thorough education on the modern video-assisted technique is mandatory for thoracic surgeons until they can fully exhaust its potential.

Invasive staging of mediastinal lymph nodes: mediastinoscopy and remediastinoscopy

Nodal status in lung cancer is essential for planning therapy and assessing prognosis. The involvement of ipsilateral and contralateral mediastinal lymph nodes is associated with poor prognosis and usually excludes patients from upfront surgical treatment. Mediastinoscopy is a time-honored procedure that allows the surgeon to access the upper mediastinal lymph nodes for either biopsy or removal. Remediastinoscopy is mainly indicated to assess objective tumor response in mediastinal lymph nodes after induction therapy for locally advanced lung cancer and to indicate further therapy.

Does video-assisted mediastinoscopy have a better lymph node yield and safety profile than conventional mediastinoscopy?

A best evidence topic was written according to a structured protocol. The question addressed was whether video-assisted mediastinoscopy (VAM) has a better lymph node yield and safety profile than the conventional mediastinoscopy (CM). A total of 194 papers were found, using the reported searches, of which five represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Two studies to date have directly compared CM and VAM with respect to lymph node yield, calculated diagnostics performance and complication rate. In both of these, lymph node yield is shown to be higher using VAM with better sensitivity, negative predictive value and accuracy rates. The favourable figures of lymph node sampling are found to be statistically significant in the single study providing such analysis. Complication rates using VAM are low, however, in the one instance where it is reported as higher than CM, the extensive lymph node dissection used in this technique may be a reasonable explanation for this finding. All studies described here exemplify VAM as a safe and useful tool in mediastinal staging, lymph node dissection and tissue diagnosis of mediastinal diseases given its superior visualization of surrounding structures and advantage of bimanual dissection. The future scope for diagnostic and therapeutic indications of cervical mediastinscopy is anticipated with recent advances and new techniques, such as video-assisted mediastinoscopic lymphadenectomy and virtual mediastinscopy.

Is video mediastinoscopy a safer and more effective procedure than conventional mediastinoscopy?

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether video-assisted mediastinoscopy (VAM) is a more effective procedure than conventional mediastinoscopy (CM). A total of 108 papers were identified using the search as discussed below. Of which, eight papers presented the best evidence to answer the clinical question as they included a sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates, number of lymph nodes biopsies, number of stations sampled and training opportunities were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. Literature search revealed that CM is a safe procedure associated with low mortality (0-0.05%) and morbidity (0-5.3%). CM has high levels of accuracy (83.8-97.2%) and negative predictive value (81-95.7%). Training in CM can be difficult as the limited vision means that the trainer cannot monitor directly the dissection and the areas biopsied by the trainee as one operator and effectively see at any time. VAM is also a safe procedure with comparable results to that of CM in term of mortality (0%), morbidity (0.83-2.9%), accuracy (87.9-98.9%) and negative predictive values (83-98.6%). The main advantage is higher number of biospsies taken (VAM, 6-8.5; CM, 5-7.13) and number of mediastinal lymph node stations sampled (VAM, 1.9-3.6; CM, 2.6-2.98). VAM can be associated with more aggressive dissecting and that can lead to more complications. The use of VAM can provide a better and safer training opportunity since both trainer and trainee can share the magnified image on the monitor. All studies available are comparing heterogeneous groups of non-matched group of patients which can bias the outcomes reported. There is a lack of comprehensive randomized studies to compare both procedures and to support any preference towards VAM over CM. We conclude that there is actually very little objective evidence of VAM superiority over CM.

Mediastinal staging procedures in lung cancer: EBUS, TBNA and mediastinoscopy

PURPOSE OF REVIEW

There is increasing awareness of minimally invasive endoscopic techniques for mediastinal staging in lung cancer. Traditionally, cervical mediastinoscopy has been utilized. Endobronchial ultrasound-guided fine needle aspiration (EBUS) has recently emerged as a potential alternative.

RECENT FINDINGS

EBUS has sensitivity for lung cancer which is at least equivalent (if not superior) to cervical mediastinoscopy. However, cervical mediastinoscopy remains superior to EBUS and other techniques in its high negative predictive value. More recent data suggest EBUS may have a role in presurgical staging of radiologically normal subcentimetre nodes and its negative predictive value may be equivalent to surgical staging. Ongoing comparative studies between EBUS and cervical mediastinoscopy may well clarify relative performance and cost analyses.

SUMMARY

Currently, insufficient data are present to recommend replacing cervical mediastinoscopy with EBUS for lung cancer staging; the negative predictive value of EBUS requires validation. However, EBUS can be recommended for initial staging as a minimally invasive option provided negative results are followed by cervical mediastinoscopy. This would also allow cervical mediastinoscopy to be reserved for re-staging. Conventional transbronchial needle aspiration has a limited role only as a first-line staging procedure but may aid diagnosis. In the future, EBUS may have a role in presurgical staging of the radiologically normal mediastinum and re-staging if prior staging is done by cervical mediastinoscopy.