The role of endobronchial ultrasound/esophageal ultrasound for evaluation of the mediastinum in lung cancer

Abstract

The introduction: of ultrasound-based, minimally invasive techniques (Endobronchial Ultrasound guided Transbronchial Needle Aspiration (EBUS-TBNA) and Esophageal Ultrasound guided Fine Needle Aspiration) has revolutionized care of patients with lung cancer needing mediastinal lymph node sampling. When combined, the techniques offer safe and accurate assessment of mediastinum, with accuracy surpassing that of the pervious gold standard – cervical mediastinoscopy. EBUS-TBNA can be used for mediastinal restaging in both, patients with suspected recurrence following treatment for primary lung cancer and followingneoadjuvant therapy in preparation for definitive surgical intervention. Both EBUS-TBNA and esophageal ultrasound guided fine needle aspiration techniques have been shown to provide sufficient material for molecular and DNA testing, extending their role beyond initial evaluation of the mediastinum to help direct and personalize medical treatment and predict response to therapy. In the future, assessing sonographic features of lymph nodesmay become useful in predicting nodal metastasis, further increasing the sensitivity of these techniques for detection of metastatic disease.

Keywords::

• EBUS-TBNA
• EUS-FNA
• lung cancer
• mediastinal staging

Financial & competing interests disclosure

K Yasafuku has received educational and research grants from Olympus Medical Systems Corp. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Conventional transbronchial needle aspiration (TBNA) is insufficient as the sole means modality in mediastinal lymph node (LN) staging in patients with lung cancer.

• Ultrasound-based techniques, endobronchial ultrasound guided (EBUS)-TBNA and esophageal ultrasound guided fine-needle aspiration are now the test of first choice for mediastinal LN staging in patients with primary lung cancer.

• In a population of patients with high pretest probability of mediastinal metastasis, negative mediastinal staging by EBUS-TBNA and or esophageal ultrasound guided fine-needle aspiration should be confirmed by surgical staging.

• EBUS-TBNA diagnostic yield is equivalent in diagnostic accuracy to that of cervical mediastinoscopy in mediastinal LN staging.

• Combined ultrasonography followed by surgical confirmation of negative results has higher sensitivity for detection of mediastinal LN metastasis than surgical staging alone, and it is more cost–effective.

• Needle-based techniques provide samples of sufficient quantity and quality for immunohistochemistry and DNA testing in patients with primary lung cancer.

Notes