Video-assisted Mediastinoscopy Research Articles

From video-assisted mediastinoscopy (VAM) to video-assisted mediastinal lymphadenectomy (VAMLA) in a low- and middle-income country: surgical technique

From video-assisted mediastinoscopy (VAM) to video-assisted mediastinal lymphadenectomy (VAMLA) in a low- and middle-income country: surgical technique

Low Cellular Sclerosis of Anterior Mediastinum

Conducting a CT-guided interventional procedure involving retrosternal pleural hydro-dissection of the juxta-aortic anterior mediastinum under local anesthesia revealed a rare histopathological condition known as benign mediastinal sclerosis. This challenging CT-guided intervention within the anterior mediastinum is scarcely documented in the existing scientific literature. In this presentation, we share our case along with relevant clinical data. What makes this case distinctive is that the clinicians initially questioned the representativeness of the biopsy sample we obtained. Consequently, an additional sample was acquired through a highly invasive video-assisted mediastinoscopy procedure under intubation anesthesia. Remarkably, this second sample yielded the same histopathological result. Mediastinal sclerosis is an exceedingly rare condition, often referred to as the "burnt-out" stage of sclerosing mediastinitis. While infectious etiologies are frequently identified (Tab.1), the majority of cases remain idiopathic [23].

Integral mediastinal staging in patients with NON-SMALL cell lung cancer and risk factors for occult N2 disease

BackgroundIn patients with non-small cell lung cancer (NSCLC), the presence of abnormal hiliar lymph nodes (clinical N1; cN1), central tumor location and/or tumor size (diameter >3 cm) increases the risk of occult mediastinal metastasis (OMM). This study investigates prospectively the diagnostic value of an integral mediastinal staging (IMS) strategy that combines EndoBronchial Ultrasound-TransBronchial Needle Aspiration (EBUS-TBNA) and Video-Assisted Mediastinoscopy (VAM) in patients with NSCLC at risk of OMM. MethodsPatients with NSCLC and radiologically normal mediastinum assessed non-invasively by positron emission tomography and computed tomography of the chest (PET-CT), and OMM risk factors (cN1, central tumor and/or >3 cm) underwent EBUS-TBNA followed by VAM if the former was negative. Those with negative IMS underwent resection surgery of the tumor. ResultsEBUS-TBNA identified OMM in 2 out of the 49 patients evaluated (4%) and VAM in 1 of the 47 patients with negative EBUS (2%). Two patients with a negative IMS had OMM at surgery. Overall, the prevalence of OMM was 10%. EBUS-TBNA has a sensitivity of 40%, a negative predictive value (NPV) of 93.6%, and negative likelihood ratio of 0.60 (95%CI:0.30–1.16). The risk of not diagnosing OMM after EBUS was 6% and after IMS was 4.4%. ConclusionIntegral mediastinal staging in patients with NSCLC and clinical risk factors for OMM, does not seem to provide added diagnostic value to that of EBUS-TBNA, except perhaps in patients with cN1 disease who deserve further research.

Confirmatory Mediastinoscopy after Negative Endobronchial Ultrasound-guided Transbronchial Needle Aspiration for Mediastinal Staging of Lung Cancer: Systematic Review and Meta-analysis.

Rationale: Current guidelines for non-small cell lung cancer (NSCLC) mediastinal staging recommend starting invasive staging with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). However, the indication to confirm a negative result of EBUS-TBNA by means of video-assisted mediastinoscopy (VAM) before resection differs in every guideline. Objectives: Our aim was to evaluate the current evidence regarding the added value of confirmatory VAM after a negative EBUS-TBNA result for mediastinal staging in patients with NSCLC. Methods: Systematic searches of studies on EBUS-TBNA for NSCLC mediastinal staging with or without confirmatory VAM but with surgical confirmation of negative results were conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement in PubMed, SCOPUS, the Cochrane Library, and guidelines from 2005 through November 2021. In the meta-analysis, the sensitivity of confirmatory VAM after a negative EBUS-TBNA result, as well as the sensitivity and negative predictive value of the combination EBUS-TBNA plus confirmatory VAM, alongside the number of confirmatory VAMs required to detect additional N2/3 disease (number needed to treat [NNT]), in patients with a previous negative EBUS-TBNA result were estimated. Results: A total of 5,412 articles were found, of which 29 studies were included. Random effects meta-analysis showed a sensitivity of 66.9% (95% confidence interval [CI], 55.8-77.1%) for confirmatory VAM, and 96.7% (95% CI, 95.1-98%) for the combination EBUS-TBNA plus confirmatory VAM. Negative predictive value in studies with confirmatory VAM increased of 79.2% (95% CI, 71.4-86.1%) for EBUS-TBNA alone to 91.8% (95% CI, 87.1-95.5%) for EBUS-TBNA plus confirmatory VAM. The NNT of confirmatory VAM in patients with a previous negative EBUS-TBNA result was 23.8 (95% CI, 19.3-31.2). Conclusions: Confirmatory VAM after negative EBUS-TBNA reduces the rate of unforeseen N2/3 disease, but with a high NNT, and it should be recommended only for certain cases yet to be defined.

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

BackgroundThe 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.MethodsA 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.ResultsTwo-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).ConclusionsWe 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.

A Case of Fibrosing Mediastinitis Mimicking Malignant Mass Lesion with Tracheal Involvement, Diagnosed by Video-assisted Mediastinoscopy

A Case of Fibrosing Mediastinitis Mimicking Malignant Mass Lesion with Tracheal Involvement, Diagnosed by Video-assisted Mediastinoscopy

Mediastinal staging for non-small cell lung cancer

The staging of mediastinal lymph nodes for lung cancer is crucial for planning treatments or reinterventions. In potentially curable patients the aim of mediastinal staging is to exclude the presence of malignancy in mediastinal lymph nodes with a high level of accuracy while also considering clinical factors and the balance of the benefits and risks of tissue sampling techniques. Mediastinal staging is based on computed tomography (CT) and positron emission tomography (PET) and can be sufficient when no mediastinal abnormalities are present and the probability of unforeseen N2 disease is low. In the case of bulky lymph nodes with a high probability of malignancy in PET-CT, tissue confirmation is not normally required. If mediastinal sampling is needed it can be achieved by endosonographic techniques, including endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) or a combination of the two. Positive results do not need further confirmation. In the case of negative results, surgical techniques still play a role in the selected cases discussed by multidisciplinary lung cancer committees. New mediastinal surgical techniques including video-assisted cervical mediastinoscopy (VACM), video-assisted mediastinoscopic lymphadenectomy (VAMLA), and transcervical extended mediastinal lymphadenectomy (TEMLA) have been shown to be useful in selected patients. Final pathological staging is based on lymph node removal during surgery and can be achieved by taking one of two approaches: lymph node sampling or systematic lymph node sampling. The accuracy of PET-CT and mediastinal endosonography is lower for mediastinal restaging than it is for surgical techniques; their false positive and false negative (FN) rate is high and so, they require histological confirmation. Here we explain and revise the results from the most recent studies and current international guidelines.

Evaluation of mediastinoscopy in mediastinal lymph node staging for non-small-cell lung cancer.

The purpose of this study was to assess the quality of video-assisted cervical mediastinoscopy (VACM) in the staging of non-small-cell lung cancer (NSCLC) at the Antwerp University Hospital with a focus on test effectiveness indicators, morbidity and unforeseen pN2 results. All consecutive VACM workups of cases of NSCLC performed between January 2010 and December 2015 were included to assess overall test quality and effectiveness. Quality assurance was performed in accordance with the recommendations of the European Society of Gastrointestinal Endoscopy and European Society of Thoracic Surgeons (ESTS) where appropriate. A total of 168 video-assisted cervical mediastinoscopies were included. A total of 91.7% of the procedures were performed in accordance with the ESTS guideline. An unforeseen pN2 staging was identified in 10 anatomical lung resections (8.6%). Statistical analysis showed no significant association between VACM performed in accordance with the ESTS guideline and the presence of pN2 positive lymph nodes [χ2 (1) = 0.61; P = 0.57] and no association between VACM performed in accordance with the ESTS guideline and overall futile thoracotomy [χ2 (1) = 0.76; P = 0.50]. Calculations revealed a sensitivity of 81.8 [95% confidence interval (CI) 69.1-90.9], specificity of 100%, positive predictive value of 100%, negative predictive value of 91.9% (95% CI 86.6-95.2) and diagnostic accuracy of 94.1% (95% CI 89.33-97.11). Overall, 91.7% of the VACM were performed in accordance with the ESTS guideline. This process resulted in a sensitivity of 81.8%, a negative predictive value of 91.9% and an unforeseen pN2 rate of 8.6%.

Clinical application of ultrasound-guided mediastinal lymph node biopsy through cervical mediastinoscopy.

BackgroundCervical mediastinoscopy is useful for diagnosing lung and mediastinal disease. Ultrasound is a safe real‐time diagnostic tool widely employed in many surgical fields. Ultrasound was used in cervical mediastinoscopy in our cohort with satisfactory results. This study investigated the safety, feasibility, and availability of video‐assisted mediastinoscopy (VAM) combined with ultrasound for mediastinal lymph node biopsy.MethodsA total of 87 cases involving cervical mediastinal lymph node biopsy performed from November 2015 to May 2020, with complete clinical and pathological information, were retrospectively analyzed in the Department of Thoracic Surgery at Beijing Chaoyang Hospital. The cohort was divided into two groups: ultrasound‐guided biopsy under video‐assisted mediastinoscopy (UVAM) (44 cases) and routine VAM (43 cases). Operation time, biopsy number and nodal stations, postoperative complications, pathological conditions, and surgical difficulty were compared between the two nodal stations.ResultsUVAM was significantly shorter and more lymph node specimens were obtained than with VAM. There was one case of fatal bleeding and two cases of right recurrent laryngeal nerve injury in the VAM group, and no postoperative complications in the UVAM group.ConclusionsWhen used with cervical VAM, ultrasound guidance assists physicians assess the space between lymph nodes, surrounding tissues, and large vessels systematically, making biopsy safer and easier, improving lymph node sampling, and decreasing postoperative complications. Furthermore, surgeons can easily learn and master this method.Key pointsSignificant findings of the study: Ultrasound was used in combination with cervical mediastinoscopy and the results showed that ultrasound guidance makes biopsy in patients safer and easier, improves lymph node sampling, and decreases postoperative complications.What this study adds: Surgeons can easily learn and master this method.

Surgical Experience of Video-Assisted Mediastinoscopy for Nonlung Cancer Diseases.

Video-assisted mediastinoscopy (VAM) is a valuable method in the investigation of diseases with mediastinal lymphadenopathy or those localized in the mediastinum. The aim of this study was to determine the diagnostic value of VAM in the investigation of mediastinal involvement of nonlung cancer diseases and to describe our institutional surgical experience. Clinical parameters such as age, sex, histological diagnosis, morbidity, and mortality of all patients who underwent VAM for the investigation of mediastinal involvement of diseases except lung cancer between January 2006 and July 2018 were retrospectively reviewed, and the diagnostic efficacy of VAM was determined statistically. During the study period, 388 patients underwent VAM, and 536 lymph nodes were sampled for histopathological evaluation of mediastinum due to mediastinal lymphadenopathy or paratracheal lesions. The most common diagnoses were sarcoidosis (n = 178 [45.9%]), tuberculous lymphadenitis (n = 108 [27.8%]), lymphadenitis with anthracosis (n = 72 [18.6%]), and lymphoma (n = 15 [3.9%]). The results of the study show that VAM should be used because of its high diagnostic benefit in mediastinal lymphadenopathies, which are difficult to diagnose, or mediastinal lesions located in the paratracheal region. Despite the increase in the number of new diagnostic modalities, VAM is still the most effective method and a gold standard.

Mediastinal Paratiroid Adenomlarının Tedavisinde SPECT/BT Rehberliğinde Uygulanan Minimal İnvazif Girişimler

Locating and removing ectopic parathyroid tissue may result in more than 20% failure. Seven cases which were detected by single photon emission computed tomography/computed tomography (SPECT/CT) imaging with Tc-99m sestamibi and treated with minimally invasive surgical methods were presented. The cases that underwent SPECT/CT due to high parathormone (PTH) level after total/subtotal parathyroidectomy operation, and detected to have mediastinal ectopic parathyroid were included. The success of the surgery was assessed with preoperative and postoperative PTH levels. Video-assisted thoracic surgery (VATS) was performed on five of the cases and video-assisted mediastinoscopy (VAM) was performed on remaining two. The mean age was 52.4±19.0. There were six women and one man. Mediastinal adenomas ranging from 1.5 to 6 cm in size, were successfully treated after single attempt. If the mediastinal ectopic parathyroid adenomas are fully localized before surgery, it can be treated with minimally invasive surgical methods.

Malignant pleural mesothelioma: current perspectives

The objectives of this study are to review epidemiology, novel methods of detection, novel diagnostics, and novel therapeutic options of malignant pleural mesothelioma (MPM) in the literature that were published between 1977 and 2019. Malignant pleural mesothelioma, associated with prolonged respirable-asbestos-fiber exposure is a rare cancer with constantly increasing incidence and poor prognosis due to lacking the effective treatment options. The median survival ranges from 8 to 14 months. Sarcomatoid histological subtype has the worst prognosis. Video-assisted thoracoscopy plus mediastinoscopy is the current gold standard for staging malignant pleural mesothelioma and is superior to computerized tomography of the chest for assessing the tumor size and suspected nodal metastases. Several circulating biomarkers are detected in MPM patients, such as mesothelin, osteopontin, fibulin-3, high mobility group B1, vascular endothelial growth factor, reactive oxygen species, reactive nitrogen species, micro-ribonucleic acids, tumor deoxyribonucleic acid, etc.Surgery is controversial and restricted to patients with early stage disease and good functional status. There is still no curative treatment whereas chemotherapy is the only treatment modality that improve patients’ survival. Radiotherapy is beneficial as a palliative treatment and an adjuvant to chemotherapy and surgery in the context of trimodality treatment. In conclusion, there is potential for the development of biomarkers and radiological imaging in the years to come. Several novel therapeutic options are under studied and it is likely to involve highly personalized treatment. Its incidenceis expected to decrease in the next decade.

Invasive mediastinal staging by endosonography or video-assisted mediastinoscopy in PET-CT clinical N1 non-small cell lung cancer.

Patients with clinical N1 (cN1) non-small cell lung cancer (NSCLC) based on PET-CT imaging are often found to have occult mediastinal nodal involvement (N2-disease) at invasive staging or resection although the PET-CT was negative on the mediastinum. Two multicenter prospective studies in patients with PET-negative mediastinum but suspected cN1-disease were performed to measure sensitivity of two invasive mediastinal staging strategies to detect mediastinal nodal disease, one with endosonography and one with video-assisted mediastinoscopy (VAM) or video-assisted mediastinoscopic lymphadenectomy (VAMLA). Consecutive patients with operable and resectable cN1 (suspected) NSCLC underwent endosonography, if negative followed by mediastinoscopy in the first study (n=100). In the second study with identical inclusion criteria, patients (n=105) underwent a VAM or VAMLA [VAM(LA)]. All patients underwent FDG-PET and CT scan prior to invasive mediastinal staging. The primary study outcome was sensitivity to detect N2-disease. Secondary endpoints were the prevalence of N2-disease, negative predictive value (NPV) and accuracy of the invasive staging procedure. In both studies, 25% of patients with cN1 disease on imaging had eventually pathology-proven N2-disease. Endosonography alone reached a sensitivity (38%) to detect mediastinal nodal disease. Invasive mediastinal staging with VAM(LA) had a sensitivity of 73% to detect N2-disease. The NPV was 92% and accuracy 93%. At endosonography, a mean of 2.1 mediastinal nodal stations were biopsied vs. 3.9 at VAM(LA). VAM(LA) has a satisfactory sensitivity of 73% to detect mediastinal nodal disease in cN1 lung cancer and could be the technique of choice for pre-resection mediastinal lymph node assessment in this patient group with a one in four chance of occult positive mediastinal nodes after negative PET-CT.

Video-assisted mediastinoscopy is safe in patients taking antiplatelet or anticoagulant therapy.

Background:The aim of this study was to report our experience with video-assisted mediastinoscopy (VAM) in patients taking antiplatelet (AP) or anticoagulant therapies focusing on perioperative complications (especially haemorrhagic).Patients and Methods:We have done a retrospective study from a prospectively maintained database with diagnostic VAM (01/2008–06/2012). We included 54 patients with AP (41 patients – Group A) and anticoagulant (13 patients – Group B) therapies. The control group was formed by 263 patients (Group C). Data regarding the clinical records of the patients, operative time, per- and post-operative complications, total numbers of biopsies and the results of the pathologic examination were collected. We compared the groups A+B versus C, and then A versus C. Statistical differences were calculated by Chi-square test.Results:In Group A, we had two minor complications: cardiac arrhythmia and peroperative minor haemorrhage. The mean operative time was 29 min and the mean post-operative stay was 1.08 days. In Group B, we had one minor complication: Peroperative minor haemorrhage. The mean operative time was 35 min and the mean post-operative stay was 1.07 days. In Group C, the mean operative time was 28 min. One death occurred (mortality rate of 0.38%) because of cardiac arrest at the induction of anaesthesia. One major complication occurred (severe respiratory insufficiency needing re-intubation) and eight minor complications. Morbidity rate was 2.28%. Mean post-operative stay was 1.14 days. No statistical difference was noted between groups.Conclusion:VAM can be safely performed in patients receiving AP or anticoagulant treatments. There is no increase in peroperative bleeding or post-operative compressive cervico-mediastinal haematoma.

Surgical experience and patient-related restrictions predict the adequacy of cervical mediastinoscopy in non-small cell lung carcinoma lymph node staging

BackgroundUntil recently, cervical mediastinoscopy was considered to be the reference standard for mediastinal staging for Non-Small Cell Lung Carcinoma (NSCLC). In the absence of metastases, mediastinal lymph node involvement is the most important prognostic factor and as such it determines therapeutic strategies. In this study we evaluated the adequacy of cervical mediastinoscopy in NSCLC lymph node staging in a large university hospital over more than a decade. In addition, we determined the influence of: (1) surgeon’s experience (2) video-assisted mediastinoscopy (VAM) and (3) patient-related restrictions (PRR) on the adequacy of lymph node sampling.MethodsBetween January 2001 and December 2014, 225 patients underwent cervical mediastinoscopy for lymph node staging. Surgical and histological data were reviewed. Thirty-day follow-up was available for all patients. Lymph node sampling was considered adequate when stations 4 L, 4R and 7 were sampled (ESTS guidelines). A surgeon was considered to be experienced when he or she performed at least 40 procedures during the study-period.ResultsIntraoperative mortality was 0%. Thirty-day mortality was 1.3%. Overall adequacy of lymph node sampling was 56%. Univariate and multivariate logistic regression analyses of lymph node sampling adequacy revealed level of surgical experience and PRR as independent predictors of lymph node sampling adequacy.ConclusionsSurgical experience and PRR independently predict the adequacy of cervical mediastinoscopy in NSCLC lymph node staging. VAM does not independently predict the adequacy of mediastinal lymph node sampling. In light of the expected further decline in mediastinoscopy numbers, we recommend to limit this procedure exclusively to the armamentarium of the experienced thoracic surgeon.

Minimally invasive esophagectomy via Sweet approach in combination with cervical mediastinoscopy for esophageal squamous cell carcinoma: a case series.

Objective:Minimally invasive esophagectomy (MIE) is increasingly used for the treatment of esophageal cancer. However, MIE via the Sweet approach has seldom been reported owing to the challenging procedure for a mediastinal lymph node. Thus, the approach of MIE via left-sided thoracoscopy coupled with video-assisted cervical mediastinoscopy (MIE-SM) was explored for eradicating the mediastinal lymph nodes and recurrent laryngeal nerve; the incidence of perioperative complications, mortality, and surgical radicality were analyzed.Materials and Methods:Thirty patients with esophageal carcinoma underwent MIE-SM between June 2014 and February 2016. The primary outcome was postoperative morbidity within 2 weeks postsurgery. The secondary outcome was surgical radicality, including the circumferential margins, and the number of lymph nodes dissected.Results:The MIE-SM was completed in all patients within 367.6±68.7 minutes. The incidences of postoperative morbidities including pulmonary complications, anastomotic leakage, chylothorax, or recurrent nerve injury were 43.3%.Conclusion:The MIE-SM was utilized for the first time to reduce the disadvantage of purely Sweet and McKeown approach, with favorable efficacy in the mediastinal and laryngeal recurrent nerve lymph node eradication. Thus, MIE-SM might be a promising alternative approach in treating esophageal cancer in selected patients.

Validity of the updated European Society of Thoracic Surgeons staging guideline in lung cancer patients

ObjectiveThe European Society of Thoracic Surgeons (ESTS) has proposed a revised preoperative lymph node staging guideline for patients with potentially resectable non–small cell lung cancer (NSCLC). We aimed to assess the validity of this revised ESTS guideline and survival results in our patient cohort. MethodsA total of 571 patients with potentially resectable NSCLC seen between January 2004 and November 2013 were included in the study. The preoperative mediastinal staging was performed by video-assisted cervical mediastinoscopy or video-assisted mediastinoscopic lymphadenectomy in all patients except those with peripheral cT1N0 nonadenocarcinoma tumors. Resection via thoracotomy or video-assisted thoracoscopic surgery was done in patients with no mediastinal lymph node metastasis. Surgical pathological results were compared with the ESTS staging guideline, and the validity of the guideline was tested. ResultsIn this series, mediastinal lymph node metastasis was revealed preoperatively in 266 patients (46.6%). A total of 305 patients underwent anatomic lung resection. The sensitivity, specificity, positive and negative predictive values, and accuracy of the guidelines were calculated as 95.0%, 100%, 100%, 94.6%, and 97.2%, respectively. ConclusionsThe ESTS revised preoperative lymph node staging guidelines for patients with NSCLC seem to be effective and valid, and may provide high survival following resectional surgery.

Diagnostic Value of Video-assisted Mediastinoscopy and Endobronchial Ultrasound-guided Transbronchial Needle Aspiration for Mediastinal Lymphadenectasis without Pulmonary Abnormalities.

BackgroundMediastinal diseases are difficult to diagnose due to diverse origins and complex anatomical structure of the mediastinal tissues. The prospective study aimed to compare the diagnostic efficiency of video-assisted mediastinoscopy (VAM) and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal lesions without pulmonary abnormalities.Material/MethodsWe divided 100 mediastinal lymphadenectasis patients without pulmonary abnormalities into a VAM group and an EBUS group. The pathological results of each group were regarded as the endpoints. SPSS19.0 statistical software was used.ResultsThe diagnostic accuracy, sensitivity, and specificity of VAM were 96%, 97.4%, and 100%, respectively; those of EBUS-TBNA diagnosis were 62%, 87.1%, and 100%, respectively. There was a statistically significant difference in the diagnostic sensitivity of benign mediastinal lesions between the 2 groups (P<0.01). Compared with the EBUS group (62%), the accuracy in the VAM group was significantly higher (96%) (P<0.01).ConclusionsWe found that the diagnostic accuracy of VAM for mediastinal lymphadenectasis without pulmonary abnormalities is superior to that of EBUS. Therefore, for patients with mediastinal lymphadenectasis or mediastinal mass and without pulmonary abnormalities, mediastinoscopy is recommended as the first choice.

PC01.02 Invasive Staging and Restaging

PC01.02 Invasive Staging and Restaging

P2.02-055 Pathologic Mediastinal Nodal and Metabolic Tumor Response to Predict Overall Survival in Stage IIIA-N2 NSCLC after Neoadjuvant Chemotherapy

Neoadjuvant chemotherapy (NCT) is a therapeutic option that is used in patients with resectable stage IIIA-N2 NSCLC. We previously hypothesized that combined major histopathological mediastinal nodal response (≤10% residual tumor cells in nodal tissue) and metabolic FDG-PET response (ΔSUVmax ≥60%) on the primary tumor could be regarded as a powerful surrogate of overall survival (OS) in stage IIIA-N2 NSCLC given NCT and confirmed mediastinal nodal disease at diagnosis. This phase II prospective multicenter study aimed to validate the predictive power for OS of our restaging algorithm. Patients with resectable stage IIIA-N2 NSCLC having mediastinal nodal disease proven by endosonography and primary tumor SUVmax at least 2.5 were eligible. All patients were scheduled for 3 cycles of NCT followed by video-assisted mediastinoscopy (VAM). A standardized PET/CT was performed at baseline, after one and three cycles. The primary endpoint was the predictive power for longer OS of a major histopathological mediastinal nodal response at VAM combined with a pre-defined primary tumor ΔSUVmax ≥60% at PET (good prognosis group) compared to all other situations (poor prognosis group). Under an assumption of a 2-year OS of 80% compared to 30% for the good versus poor prognosis group, respectively, 48 patients were required to have 80% power with 2-sided alpha of 0.05. We enrolled 32 patients between 2009 and 2014. Two patients demonstrated stage IV at PET/CT after cycle one. All 3 cycles were given to 30 patients of whom 29 underwent VAM and 22 underwent surgical resection. Objective response rate (RECIST 1.1) was 44%. Complete pathological response occurred in 2 patients. Median OS was 26 months (all 2-year events occurred). In ITT, combined major histopathologic nodal and metabolic tumor response was associated with a trend towards longer OS (HR 0.29, 95%CI 0.14-1.09, P=0.07). Major histopathologic mediastinal nodal response was significantly associated with longer OS (HR 0.25, 95%CI 0.02-0.51, P=0.006), while metabolic ΔSUVmax ≥60% primary tumor response was only associated with a trend towards better OS (HR 0.41, 95%CI 0.17-1.27, P=0.14). Complete pathological response to NCT in stage IIIA-N2 NSCLC is infrequent and therefore not useful as a surrogate for OS. Combined major pathologic nodal and metabolic tumor response was associated with a trend towards longer OS. By contrast, a major histopathologic mediastinal nodal response with ≤10% residual tumor cells at VAM is well suited to be adopted as a surrogate of OS.