Comparative analysis of genetic variants in pleural fluids and solid tissue biopsies of pleural mesothelioma patients: Implications for molecular heterogeneity assessment.

Objectives: This study aims to determine whether the sequencing of DNA extracted from pleural fluids (PFs) of Pleural Mesothelioma (PM) patients accurately represents the genetic information obtained from the solid tissue counterpart biopsies with particular attention to the identification of single nucleotide variants (SNVs). Materials and methods: Single pleural biopsy, PFs, and blood were collected from PM patients. DNA was extracted from these samples and then subjected to Whole-Exome Sequencing. Results: A higher number of SNVs was identified in PFs than in solid tissue biopsies (STBs). Most SNVs were detected in PFs samples but not in STBs samples, while only a few SNVs were detected in STBs samples but not in PFs samples. Conclusion: The current findings support the notion that PFs might offer a more robust depiction of cancer's molecular diversity. Nonetheless, the current outcomes challenge the assertion that liquid biopsies can encompass the entirety of intra-patient variations. Indeed, a subset of potential cancer-driver SNVs was exclusively identified in STBs. However, relying solely on STBs would have precluded the detection of significant SNVs that were exclusively present in PFs. This implies that while PFs serve as a valuable complement to STBs, they do not supplant them.

Lung Metastasectomy: Where Do We Stand? Results from an Italian Multicentric Prospective Database.

Background/Objectives: The surgical resection of pulmonary metastases is considered a therapeutic option in selected cases. In light of this, we present the results from a national multicenter prospective registry of lung metastasectomy. Methods: This retrospective analysis involves data collected prospectively and consecutively in a national multicentric Italian database, including patients who underwent lung metastasectomy. The primary endpoints were the analysis of morbidity and overall survival (OS), with secondary endpoints focusing on the analysis of potential risk factors affecting both morbidity and OS. Results: A total 470 lung procedures were performed (4 pneumonectomies, 46 lobectomies/bilobectomies, 13 segmentectomies and 407 wedge resections) on 461 patients (258 men and 203 women, mean age of 63.1 years). The majority of patients had metastases from colorectal cancer (45.8%). In most cases (63.6%), patients had only one lung metastasis. A minimally invasive approach was chosen in 143 cases (30.4%). The mean operative time was 118 min, with no reported deaths. Morbidity most frequently consisted of prolonged air leaking and bleeding, but no re-intervention was required. Statistical analysis revealed that morbidity was significantly affected by operative time and pulmonary comorbidities, while OS was significantly affected by disease-free interval (DFI) > 24 months (p = 0.005), epithelial histology (p = 0.001) and colorectal histology (p = 0.004) during univariate analysis. No significant correlation was found between OS and age, gender, surgical approach, surgical extent, surgical device, the number of resected metastases, lesion diameter, the site of lesions and nodal involvement. Multivariate analysis of OS confirmed that only epithelial histology and DFI were risk-factors, with p-values of 0.041 and 0.031, respectively. Conclusions: Lung metastasectomy appears to be a safe procedure, with acceptable morbidity, even with a minimally invasive approach. However, it remains a local treatment of a systemic disease. Therefore, careful attention should be paid to selecting patients who could truly benefit from surgical intervention.

Pathological T3 Non-Small Cell Lung Cancer with satellite nodules: Number or size, what does matter?

BACKGROUND: Non-small Cell Lung Cancer (NSCLC) with intralobar satellite nodule are defined as T3 (T3SN). We investigated the main features of these tumors and analyzed their impact on Overall Survival (OS). METHODS: This was a retrospective multicentric study including all pT3SN NSCLC operated on between 2005 and 2020, excluding patients with multifocal ground-glass opacities; who received induction therapies; N3 or stage IV. The diameter of largest (LgN) and smallest nodule (SmN), the total diameter (sum of diameter of all nodules, TS), and the number of SN were measured. RESULTS: Among 102 patients, 64.7 % were male. 84.3 % of patients had one SN (84.3 %), 9.8 % two SN while 5.9 % more than 2 SN. 63 patients were pN0. LgN (p = 0.001), SN (p = 0.005) and TS (p = 0.014) were significantly related to lymph-node metastasis; the LgN and TS were related to visceral pleural invasion (p < 0.001). Five-year OS was 65.1 %; at univariable analysis more than 2 satellite nodules, LgN and TS were significantly related to worse OS; at multivariable analysis, TS (Hazard Ratio [HR] 1.116 95 % Confidence Interval [CI] 1.008-1.235, p = 0.034) was an independent prognostic factors for OS. No significant prognostic factors were found for DFS at multivariable analysis. In pN0 patients, LgN (HR 1.051, 95 % CI 1.066-1.099, p = 0.027) and non-adenocarcinoma (HR 5.315 CI 95 % 1.494-18.910, p = 0.010) influenced OS. CONCLUSIONS: Tumor size is related to tumor's local invasiveness. TS is an independent prognostic factor for OS. Patients with more than 2 SN seem to be at higher risk for death and recurrence.

Survival Outcome After Surgery in Patients With Thymoma Distant Recurrence.

OBJECTIVE: The aim of this study is to describe characteristics and survival outcome of patients who underwent surgical treatment for distant thymoma relapse according to the definition of the International Thymic Malignancy Interest Group. METHODS: Data of patients affected by thymoma recurrence from four different institutions were collected and retrospectively reviewed. Patients with locoregional metastases who underwent nonsurgical therapies and with incomplete data on follow-up were excluded. According to the International Thymic Malignancy Interest Group distant recurrence definition, patients with recurrence due to hematogenic localization were included. Clinical and pathologic characteristics were described using descriptive statistics, whereas survival outcome was calculated using Kaplan-Meier curves and Cox regression analysis. RESULTS: The analysis was conducted on 40 patients. A single localization was present in 13 patients, the relapse was intrathoracic in 28 cases (70%), and lung involvement was found in 26 cases. The liver was operated in seven cases, whereas other kinds of abdominal involvement were detected in eight cases. Adjuvant treatment was administered in 22 cases (55%).Five- and 10-year overall survival (OS) were 67% and 30%, respectively. Univariable analysis identified as significant favorable factor a low-grade histology (A, B1, B2): five-year OS at 92.3% versus 53.3% in high-grade (B3-C) (p = 0.035). Site of recurrence and number of localization did not influence the prognosis, but in patients with adjuvant therapy administration, there was a survival advantage also if not statistically significant: five-year OS 84.8% versus 54.5% in patients without adjuvant therapy (p = 0.101).Multivariable analysis confirmed as independent prognostic factor low-grade histology: hazard ratio = 0.176, 95% confidence interval 0.042-0.744, p = 0.018. CONCLUSIONS: Our study revealed a good survival outcome in patients who underwent surgery for distant thymoma recurrence, independently from the number and site of the relapse localization. Patients with A, B1, or B2 histology presented a significantly better survival than patients with B3-C.

Early-Stage Non-Small Cell Lung Cancer: Prevalence of Actionable Alterations in a Monocentric Consecutive Cohort.

Early-stage (ES) non-small cell lung cancer (NSCLC) is diagnosed in about 30% of cases. The preferred treatment is surgery, but a significant proportion of patients experience recurrence. Neoadjuvant and adjuvant chemotherapy has a limited clinical benefit. EGFR tyrosine kinase inhibitors and immunotherapy have recently opened new therapeutic scenarios. However, only a few data are available about the ES-NSCLC molecular landscape and the impact of oncogene addiction on therapy definition. Here, we determined the prevalence of the main lung cancer driver alterations in a monocentric consecutive cohort. Molecular analysis was performed on 1122 cases, including 368 ES and 754 advanced NSCLC. The prevalence of actionable alterations was similar between early and advanced stages. ES-NSCLC was significantly enriched for MET exon-14 skipping alterations and presented a lower prevalence of BRAF p.(V600E) mutation. PD-L1 expression levels, evaluated according to actionable alterations, were higher in advanced than early tumors harboring EGFR, KRAS, MET alterations and gene fusions. Taken together, these results confirm the value of biomarker testing in ES-NSCLC. Although approved targeted therapies for ES-NSCLC are still limited, the identification of actionable alterations could improve patients' selection for immunotherapy, favoring the enrollment in clinical trials and allowing a faster treatment start at disease recurrence.

Endobronchial ultrasound-transbronchial needle aspiration: effectiveness and accuracy in non-small cell lung cancer staging.

INTRODUCTION: Endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) has a cardinal role in the diagnosis and staging of non-small cell lung cancer (NSCLC), providing an accurate nodal staging in a less invasive way than surgical biopsy. The aim of this study was to assess the diagnostic accuracy of EBUS-TBNA in the pre-operative NSCLC mediastinal staging, as well as to evaluate EBUS-TBNA specificity and sensibility in our cohort. METHODS: We retrospectively analyzed data of NSCLC patients who underwent EBUS-TBNA followed by major pulmonary resection between January 2020 and December 2022. EBUS-TBNA was performed in patients with NSCLC (central T ≤ 3 cm, peripheral/central T > 3 cm), following the ESTS guidelines. The target nodes were selected on the basis of their radiologic/metabolic characteristics. Each procedure was conducted together with rapid on-site cytological evaluation (ROSE). RESULTS: Twenty-five patients were included (M/F = 17/8). At least three needle passages on each target lymph node were performed. No complications during or after the procedures occurred. We found a 100% correspondence between ROSE on the sampled nodes and postoperative pathologic findings. An upstaging occurred in three cases (12%) because of the involvement of stations 5 and 6 (not accessible via EBUS), while the only case of downstaging (N2 → N0, 4%) was probably due to intercurrent neoadjuvant chemotherapy. In all cases, EBUS-TBNA has proved to achieve a diagnostic procedure on the target nodes. CONCLUSIONS: EBUS-TBNA is a safe and effective procedure that offers high sensitivity and specificity when performed together with ROSE, which improves the accuracy of sampling. Doubt on nodal stations 5 and 6 involvement should be settled by other techniques.

TNM Staging System in Thymoma: A Critical Appraisal?

Thymomas are rare tumors of the anterior mediastinum with peculiar clinical and pathological features. They have been deeply analyzed by pioneer authors, who strictly linked their name to the main pathological and staging classifications. Before the latest edition of the WHO classification of thymic epithelial tumors, the history of thymoma pathological classification inherited the name of the pathologists who systematically addressed the issue, from Levine-Rosai to Muller-Hermelink. Similarly, the thymoma staging system is intimately related to the name of two surgeons, Masaoka and Koga, who historically dealt with this disease. More recently, the traditional tumor-nodes-metastasis (TNM) system has been developed for the staging of this condition, in a rational attempt to put thymomas in conformity with the other solid tumors. The efforts of the International Thymic Malignancies Interest Group (ITMIG) and the Thymic Domain of the Staging and Prognostic Factors Committee (TD-SPFC) of the International Association for the Study of Lung Cancer (IASLC) resulted in the TNM classification of thymic tumors, which have been included in the eighth edition of the American Joint Committee on Cancer's (AJCC) Cancer Staging Manual. Herein, we report a narrative review of the evolution of the thymic epithelial tumors (TET) staging system and present a critical appraisal of the actual TNM classification compared with the historical Masaoka-Koga classification, with special focus on the proposal for the ninth edition of the TNM, expected in 2024.

Somatic mutations of thymic epithelial tumors with myasthenia gravis.

Background: Thymic epithelial tumors are rare malignant neoplasms that are frequently associated with paraneoplastic syndromes, especially myasthenia gravis. GTF2I is an oncogene mutated in a subgroup of thymomas that is reputed to drive their growth. However, for GTF2I wild-type tumors, the relevant mutations remain to be identified. Methods: We performed a meta-analysis and identified 4,208 mutations in 339 patients. We defined a panel of 63 genes frequently mutated in thymic epithelial tumors, which we used to design a custom assay for next-generation sequencing. We sequenced tumor DNA from 67 thymomas of patients with myasthenia gravis who underwent resection in our institution. Results: Among the 67 thymomas, there were 238 mutations, 83 of which were in coding sequences. There were 14 GTF2I mutations in 6 A, 5 AB, 2 B2 thymomas, and one in a thymoma with unspecified histology. No other oncogenes showed recurrent mutations, while sixteen tumor suppressor genes were predicted to be inactivated. Even with a dedicated assay for the identification of specific somatic mutations in thymic epithelial tumors, only GTF2I mutations were found to be significantly recurrent. Conclusion: Our evaluation provides insights into the mutational landscape of thymic epithelial tumors, identifies recurrent mutations in different histotypes, and describes the design and implementation of a custom panel for targeted resequencing. These findings contribute to a better understanding of the genetic basis of thymic epithelial tumors and may have implications for future research and treatment strategies.

Surgical treatment of tracheal stenosis during Covid-19 era: a single-center experience and lessons learnt on the field.

SARS-CoV2 outbreak led to several healthcare system challenges, especially concerning respiratory support to Covid-19 patients. In the first 2 years of pandemic (2020-2021), we assisted to a marked increase of post-invasive mechanical ventilation (IMV) tracheal stenosis incidence, many of them requiring surgical treatment, namely resection and primary end-to-end anastomosis. Our aim is to describe our experience during the abovementioned biennium, focusing on postoperative outcomes of patients who have had Covid-19 ("post-Covid"). We retrospectively collected pre-, intra- and postoperative data on all patients who underwent tracheal surgery for benign stenosis in our Unit from May 2020 to October 2021, including previous Covid-19. Comparison between "post-Covid-19" and "non-Covid-19" groups' outcomes was then performed. Patients were 9 males and 6 females, and mean age was 57.4 ± 13.21 years. Nine patients had previous Covid-19 (60%). All patients underwent multidisciplinary preoperative evaluation. Almost every operation was conducted by cervicotomy, and the mean length of the resected specimen was 23.9 ± 6.5 mm. Postoperative complications were: dysphonia (3 cases), wound infection (1), bleeding (1), ab-ingestis pneumonia (1), anastomosis dehiscence (2), and stenosis recurrence (1). Thirty-day mortality rate was 6.7% (1 patient). No significant differences between "post-Covid-19" and "non-Covid-19" groups were identified. Pathology revealed, in 5 "post-Covid-19" patients, signs of vasculitis or perivascular inflammatory infiltrate. Tracheal stenosis' surgical treatment has always been known as a challenging procedure because of high perioperative morbidity and mortality rates. Our experience shows that previous Covid-19 and ongoing pandemic did not significantly affect perioperative outcomes of patients who underwent tracheal resection and primary end-to-end anastomosis in a high-volume Center and after multidisciplinary workup.

Thymectomy in severe (Myasthenia Gravis Foundation of America classes IV-V) generalized myasthenia gravis: is the game really worth the candle?

OBJECTIVES: Total thymectomy in addition to medical treatment is an accepted standard therapy for myasthenia gravis (MG). Patients with severe generalized MG present life-threatening events, poor prognosis and higher risk of postoperative myasthenic crisis. The aim of our study is to investigate neurological and surgical results in patients with Myasthenia Gravis Foundation of America (MGFA) class IV and V MG following thymectomy. METHODS: Data on 76 MG patients with preoperative MGFA classes IV and V who underwent thymectomy were retrospectively collected. Primary end points included short-term surgical outcomes and long-term neurological results including the achievement of complete stable remission and any improvement as defined by MGFA Post-Intervention Status criteria. RESULTS: There were 27 (35.5%) males and 49 (64.5%) females; 53 (69.7%) were classified as MGFA class IV and 23 (30.3%) as class V. Thymectomy was performed through sternotomy in 25 (32.9%) patients, Video-assisted thoracic surgery (VATS) in 5 (6.6%) and Robot-assisted thoracic surgery (RATS) in 46 (60.5%). The median operative time was 120 (interquartile range: 95; 148) min. In-hospital mortality was observed in 1 (1.3%) patient and postoperative complications in 14 (18.4%) patients. The median postoperative hospital stay was 4 (interquartile range: 3; 6) days. Pathological examination revealed 31 (40.8%) thymic hyperplasia/other benign and 45 (59.2%) thymomas. Cumulative complete stable remission and improvement probabilities were 20.6% and 83.7% at 5 years and 66.9% and 97.6% at 10 years, respectively. A significant improvement rate was found in patients with age at the time of thymectomy of ≤50 years (P = 0.0236), MGFA class V (P = 0.0154) and acetylcholine receptor antibodies positivity (P = 0.0152). CONCLUSIONS: Thymectomy in patients with severe MG yields good perioperative outcomes and satisfactory long-term neurological improvement, especially for patients younger than 50 years, with MGFA class V and anti-AChR+ MG.

Unradical Surgery for Locally-Advanced Thymoma: Is it time to evolve Perspectives?

OBJECTIVES: Nearly-one-third of thymomas are locally-advanced at diagnosis. The traditional dogma that surgery is justified in case a complete resection can be achieved has remained unmovable until today. This study aimed to investigate feasibility and oncologic efficacy of incomplete resection for locally-advanced thymomas in a contest of multimodality therapy. MATERIALS AND METHODS: A retrospective analysis was conducted using data of prospectively maintained thymomas database in a single high-volume centre. Data on 285 consecutive patients undergoing surgery for stage III and IVa thymomas between 1995 and 2019 were reviewed. Patients who underwent incomplete resection with curative-intent (removal of at least 90% of tumour burden) were included. Long-term outcomes and predictors of cancer-specific survival (CSS) and progression-free survival (PFS) were analyzed. Secondary endpoint was to assess adjuvant therapy efficacy. RESULTS: The study included 79 patients, 60 with microscopic residual tumour (76%, R1) and 19 with macroscopic residual disease (24%, R2). Masaoka-Koga stage was: III in 41 patients (52%) and IVa in 38 (48%). Histology was B2-thymomas (n = 31, 39.2%) followed by B3 (n = 27, 34.2%). Five- and 10-years CSS was 88% and 80%. Seventy patients (90%) underwent adjuvant treatment; they showed CSS comparable to radical resected patients (5-years: 89.1% vs 98.9%, respectively; 10-years: 81.8% vs 92.7%, respectively, p = 0.43). The site of residual disease, Masaoka-Koga stage and WHO histology did not affect prognosis. Stepwise multivariable analysis confirmed adjuvant therapy as a favourable CSS prognostic factor (HR, 0.51; 95% CI, 0.33-0.79, p = 0.003). Stratifying by subgroups, R2-patients who received postoperative chemo(radio)therapy (pCRT) showed a significantly better prognosis than R2-patients treated by consolidation radiotherapy alone (10-years CSS: 60%, p < 0.001). CONCLUSION: In locally-advanced thymomas, whenever a radical surgery cannot be achieved, incomplete resection has proved to be effective in a contest of multimodality strategy, independently of WHO histology, Masaoka-Koga stage and site of residual disease.

Cold coagulation in thoracoscopic treatment of primary pneumothorax: a comparison with apicectomy.

OBJECTIVES: Primary spontaneous pneumothorax is a common disease, whose surgical treatment is still enigmatic in terms of timing and technique. Herein, we reported our experience with the parenchymal-sparing technique via cold coagulation (CC), in comparison to stapler apicectomy (SA). METHODS: We retrospectively collected data of all patients with apical blebs or <2 cm bullae treated with minimally invasive surgery for recurrent or persistent spontaneous pneumothorax, from 2010 to 2020. Two different surgical techniques were used: SA and the parenchymal-sparing CC of the apex. Perioperative and long-term results were analysed and compared. RESULTS: Out of 177 patients enrolled, 77 patients (CC group) underwent cold-coagulation of the apex while 100 patients (SA group) were treated with SA. Two groups were comparable in terms of age, surgical indication, intraoperative findings and affected side. CC group had a mean operative time of 43.2 min (standard deviation ± 19.5), shorter than SA group with 49.3 min (standard deviation ± 20.1, P-value: 0.050). Complication rate was significantly different between 2 groups, 5 (7%) and 16 (16%), for the CC and SA groups, respectively (P: 0.048), even if not in terms of prolonged postoperative air leak (P: 0.16). During the follow-up, 13 homolateral recurrences were reported: 2 (3%) in group CC and 11 (11%) in group SA; with a significant difference (P: 0.044). All reinterventions (postoperative prolonged air leak and recurrences) required an SA. CONCLUSIONS: Parenchymal-sparing technique through CC of apical blebs and bullae is an effective treatment for primary spontaneous pneumothorax and guarantees a good immediate lung sealing, despite stapling still represents the choice treatment in complex cases.

Intraoperative prevention and conservative management of postoperative prolonged air leak after lung resection: a systematic review.

Background: Prolonged air leak (PAL) due to an alveolar-pleural fistula (APF) is the most common complication after lung surgery. PAL is associated with an increased risk of morbidity and mortality, a longer chest tube duration, hence a prolonged hospitalization. Management of PAL may be challenging, and the thoracic surgeon should be aware of the possible therapeutic strategies. Methods: A systematic literature review was performed in PubMed, Cochrane Library, EMBASE, Ovid and Google Scholar. Title, abstract and full-text screening was performed, followed by structured data extraction, methodological quality assessment and Cochrane risk of bias assessment. Inclusion criteria were: case-control studies/randomized controlled trials (RCTs) comparing the new tested method with the standard of care to manage PAL after lung surgery; PAL due to APF; at least 10 patients; English-written papers. Results: A total of 942 initial papers from literature search, resulted in 43 papers after the selection. This systematic review found that the use of intraoperative measures as surgical sealants or pleural tenting, as well as a proper management of the chest drain and the use of blood patch or sclerosant agents seem to reduce postoperative air leaks incidence and/or duration and length of chest drain stay and hospitalization. Conclusions: Different measures have been described in literature to manage or prevent postoperative PAL. Most of them seem to be safe and efficient if compared to the "wait and see" strategy, even if large comparative studies that standardize the intra- and post-operative management of APF after lung resection are lacking and, actually, hard to conceptualize. However, there is a large consensus on the value of a preoperative PAL-risk stratification and on the necessity of tailoring PAL management or prevention's strategy and its timing on each patient's features.

An asymptomatic giant AB thymoma in a patient with Down syndrome: a case report.

Background: Mediastinal mass management may represent a real challenge for all the physicians who deal with it. Mediastinum, in fact, contains different vital structures which are often involved by growing neoplasms with increasing severity. Therefore, up to 60% of the patients with mediastinal mass are symptomatic, according to the structure involved. Different neoplasms may arise essentially from all mediastinal organs, whereas thymic epithelial tumors and lymphomas represent more than 90% of mediastinal tumors. Case Description: We report the first case described of a giant asymptomatic mediastinal mass in a 43-year-old male affected by Down syndrome (DS), turned out to be a thymoma, treated exclusively and successfully with radical surgery. Despite the absence of any symptoms, the giant thymoma infiltrated the diaphragm, the pericardium, the upper lobe of the left lung together with the left phrenic nerve resulting in the compression of heart and great vessels. Conclusions: To date, this is the first description of a thymic malignancy in a patient with DS, that usually is characterized by a low-incidence of solid tumor except for germ-cells ones. Surgery has been extremely challenging, due the clinical condition of the patient together with the tumor features; nevertheless, oncological radicality criteria were completely fulfilled. After four years from surgery, the patient is alive and still disease-free, highlighting the importance of radical surgery.

New Insights in Pleural Mesothelioma Classification Update: Diagnostic Traps and Prognostic Implications.

The 2021 WHO Classification of Tumors of the Pleura has introduced significant changes in mesothelioma codification beyond the three current histological subtypes-epithelioid, sarcomatoid and biphasic. Major advances since the 2015 WHO classification include nuclear grading and the introduction of architectural patterns, cytological and stromal features for epithelioid diffuse mesothelioma. Mesothelioma in situ has been recognized as a diagnostic category. Demonstration of loss of BAP1 or MTAP by immunohistochemistry, or CDKN2A homozygous deletion by FISH, is valuable in establishing the diagnosis of epithelioid mesothelioma. Recent emerging data proved that grading and histological subtypes have prognostic implications and may be helpful to patient risk stratification and clinical management. Nevertheless, the latest mesothelioma classification increases the already non-negligible diagnostic pitfalls, especially concerning differential diagnosis of pre-invasive tumors. In this review, recent changes in histologic classification of mesothelioma and advances in molecular markers are presented and their relation to diagnostic challenges and prognostic implications is discussed.