An approach to the surgical pathology of tumours and tumour-like conditions of the liver

Hepatic masses are increasingly being found, often as a result of more frequent and sophisticated imaging. Lesions can be detected during screening for primary and metastatic tumours, or as an incidental finding. Although some have distinctive radiological appearances allowing for a confident diagnosis, histological assessment of biopsy and resection specimens remains the cornerstone for the correct identification of many lesions. This broadsheet describes the distinctive features of common and uncommon hepatic tumours and outlines diagnostic problems and pitfalls, particularly for the benign and malignant tumours of hepatocytes and bile ducts. Tumour-like lesions that mimic malignancy are also discussed. Finally, an approach to the assessment of biopsies from probable metastatic tumours is presented, as this is one of the most common indications for liver mass biopsy for the practising pathologist.