ACR appropriateness criteria® radiologic management of thoracic nodules and masses.

Pulmonary and mediastinal masses represent a wide range of pathologic processes with very different treatment options. Although advances in imaging (such as PET and high-resolution CT) help in many cases with the differential diagnosis of thoracic pathology, tissue samples are frequently needed to determine the best management for patients presenting with thoracic masses. There are many options for obtaining tissue samples, each of which has its own set of benefits and drawbacks. The purposes of this report are to present the most current evidence regarding biopsies of thoracic nodules and masses and to present the most appropriate options for select common clinical scenarios. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.