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

Surgical access to the mediastinum-all roads lead to Rome: a literature review

Background and Objective

The mediastinum is a complex, heterogeneous area, which leads vertically across the thoracic cavity between the bilateral mediastinal pleurae, connecting the head and neck region with the thoracic cavity. Different classifications have been published to differentiate between the so-called mediastinal compartments while the most used classification surely is the 4-compartments Gray`s classification, dividing it into the superior, anterior, middle and posterior mediastinum. Mediastinal abnormalities include infections (mediastinitis) and solid or cystic mediastinal masses. These masses can be divided into benign and malignant lesions originating from mediastinal structures/organs or represent manifestations of metastatic disease, often metastatic non-small cell lung cancer (NSCLC). This review aims to explore the different mediastinal pathologies along with indications and surgical approaches.

Methods

We performed literature research in PubMed, MEDLINE, Embase, CENTRAL, and CINAHL databases. Only papers written in English were included.

Key Content and Findings

Depending on the indication for surgical intervention and the localization of the pathology, surgical approach may differ immensely. Mediastinal staging of lung cancer, primary lesions of the mediastinum, mediastinitis and traumatic mediastinal injuries display the most frequent indications for mediastinal surgery. Surgical approaches trend towards minimally invasive, video- or robotic-assisted techniques and are becoming increasingly refined to adapt to the special characteristics of the mediastinum. However, certain indications still require open access for best possible mediastinal exposure or oncological reasons.

Conclusions

To guide optimal surgical approach selection to the mediastinum, the following overview will present all published surgical approaches to the mediastinum and discuss their practical relevance and indications aiming to help surgeons in the management of patients with mediastinal pathologies who should undergo surgery.

N1-positive non-small cell lung cancer: surgeons' perspective before undertaking a major resection

Among various reasons for a rise in surgical referrals for locally advanced non-small cell lung cancer, few are improved clinical-pathological staging, better understanding of oncological driver mutation, and aggressive neoadjuvant treatment options. These cases with positive ipsilateral bronchopulmonary lymph nodes are intriguing subset where multiple treatment options have been explored to improve disease-free survival. Targeted neoadjuvant therapy followed by surgical resection is becoming a new norm and surgeons are referred these complex cases. This narrative review is highlighting the importance of proper preoperative staging, contemporary practices in surgical decision-making, and procedural aspect of hilar node dissection.

Surgical Experience of Video-Assisted Mediastinoscopy for Nonlung Cancer Diseases

BACKGROUND

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.

METHODS

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.

RESULTS

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%]).

CONCLUSION

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.

miR‑671‑3p is downregulated in non‑small cell lung cancer and inhibits cancer progression by directly targeting CCND2

MicroRNAs (miRNAs) are implicated in the development and progression of non‑small cell lung cancer (NSCLC). A previous study suggested that miR‑671‑3p suppresses the development of breast cancer. However, the role of miR‑671‑3p in NSCLC remains largely unknown. In the present study, it was identified that miR‑671‑3p was significantly upregulated in NSCLC tissues compared with adjacent normal tissues by reverse transcription quantitative polymerase chain reaction (RT‑qPCR). Similarly, decreased levels of miR‑671‑3p in NSCLC cell lines were observed compared with those in the non‑tumorigenic human bronchial epithelial NL20 cell line. Cell Counting Kit‑8 and Transwell invasion assays indicated that miR‑671‑3p overexpression suppressed the proliferation and invasion of A549 cells, and vice versa. Mechanistically, it was demonstrated that CCND2 was a direct target of miR‑671‑3p. RT‑qPCR and western blot analysis indicated that miR‑671‑3p overexpression decreased the expression of CCND2 in A549 cells. Furthermore, rescue experiments demonstrated that the restoration of CCND2 may significantly reverse the suppressive roles of miR‑671‑3p overexpression on NSCLC cell proliferation and invasion. Taken together, the present study demonstrated that miR‑671‑3p exerted its tumor‑suppressive roles via directly targeting CCND2 in NSCLC.

Endobronchial ultrasound-transbronchial needle aspiration (EBUS/TBNA): a diagnostic challenge for mediastinal lesions

Lung cancer is one of the most frequent neoplastic diseases. To date, most lung cancer is diagnosed at an advanced stage, making it difficult to choose the diagnostic and therapeutic strategy. Surgical resection represents the best therapeutic solution. However, the best results are obtained only in the early stages of the disease. Lymph node involvement conditions the treatment (surgical or non-surgical approach). Mediastinoscopy is an effective and widely used method for mediastinal staging but does not allow us to reach many mediastinal lymph nodes. Endobronchial ultrasound/transbronchial needle aspiration (EBUS-TBNA) allows us to reach more lymph nodes and is referred to as a first-choice exam for mediastinal staging.

MicroRNA-214 inhibits the proliferation and invasion of lung carcinoma cells by targeting JAK1

Increasing evidence suggests that microRNAs (miRNAs) play a crucial role in the pathogenesis of tumor. In this study, miR-214 was found to be significantly down-regulated in lung tumor tissues and lung cell lines. From the gain-of-function experiment results, we found that ectopic expression of miR-214 in lung cancer cell lines significantly inhibited cell growth, as evidenced by cell viability and colony formation assays, and suppressed tumor growth in vivo. Besides, further investigations showed that miR-214 inhibited cell migration and invasion. The luciferase activity assay revealed that oncogene Janus kinase 1 (JAK1) was a direct target gene of miR-214, and its expression was inversely correlated with that of miR-214. Altogether, our findings demonstrated that miR-214 plays a pivotal role in lung cancer by inhibiting cell proliferation, invasion and migration by targeting oncogenic JAK1, and thus, miR-214 may provide a new potential therapeutic target in lung cancer.