Mediastinal Biopsy Techniques

Abstract

The mediastinum is the central region of the thoracic cavity that contains many vital structures, all of which may give rise to a tumor or other abnormality associated with a disease process. In addition, the vast majority of mediastinal lesions require tissue sampling prior to initiating a treatment plan. Since the mediastinum is filled with vital structures, the performance of biopsies carries an inherent risk of injury to these surrounding structures. Historically, mediastinal biopsies were challenging, and oftentimes biopsies needed to be performed using a formal surgical procedure, commonly with general anesthesia. In recent years, however, technologies involving minimally invasive techniques and image guidance have evolved to the point that the mediastinum is easily accessed in most circumstances, with little trauma to the patient. The choice of technique to utilize for biopsy depends on the anatomic location of the lesion, as well as the intent of the biopsy. In this regard, the mediastinum is anatomically divided into compartments, which is useful in selecting a biopsy technique. Further, while some biopsies are performed simply to obtain a histologic diagnosis, other biopsies are also therapeutic because the entire abnormality may be excised. Finally, sometimes tissue acquisition is indicated in order to perform molecular and genetic testing for some tumors. The clinician should be familiar with these issues when deciding on the optimal biopsy approach.