Diagnostic approach to needle biopsies of hepatic mass lesions

In clinical practice, a wide variety of benign and malignant lesions present as hepatic masses and are subjected to needle biopsy. For practical purposes, these lesions can be broadly classified into: (1) clearly hepatocytic and malignant; (2) clearly hepatocytic and of uncertain clinical nature and malignant potential; (3) clearly malignant and of uncertain lineage; and (4) neither clearly hepatocellular nor malignant. The diagnostic approach to each of these varies and requires integration of clinical, laboratory and imaging findings. Work-up often requires histochemical and immunohistochemical stains, which should be judiciously selected based on the H&E morphological pattern and the differential diagnosis. No single stain or standard composite panel of stains currently exists that is uniformly applicable. This review addresses appropriate triage of these biopsies and outlines a practical approach to the diagnosis of hepatic mass lesions, to encourage judicious use of resources, minimizing cost and time, and maximizing efficiency.