Management of an Incidental Liver Mass

The wide availability and use of advanced imaging modalities, including ultrasonography (US), CT, MRI, and positron emission tomography (PET), have led to increased identification of incidental liver masses (ILMs). The discovery of an ILM typically occurs during the course of an evaluation for an unrelated suspected or existing clinical problem. ILMs have also been detected during whole-body cross-sectional imaging offered on a proprietary basis for screening purposes. 1 On detection of ILM, it is incumbent on caring physicians to balance the potential risks posed by a lesion with the costs of further evaluation or treatment. Real harm can result from failure to diagnose a malignancy or inappropriate work-up of a harmless lesion. Through careful consideration of patient factors and imaging characteristics of ILMs, clinicians can recommend a safe, effective, and efficient course of action. This article begins by considering the clinical factors that should be incorporated into the risk assessment of ILMs. Subsequently, the radiologic features of ILMs are reviewed, which are used in conjunction with clinical circumstances to define the risk of malignancy and the need for further evaluation and management. Specific indications for biopsy or therapeutic intervention are discussed. The article concludes with consideration of the specific pathologic entities accounting for the majority of ILMs. An algorithmic approach is outlined as a conceptual framework to assist with the development of an individualized assessment and management strategy for each patient confronted with an ILM (Fig. 1). CLINICAL FACTORS RELATED TO INCIDENTAL LIVER MASS RISK Although most of this discussion focuses on the radiographic or physical characteristics of ILMs, placing incidental imaging findings in the appropriate clinical context is of the utmost importance. Factors, including patient age, gender, history of malignancy