Case ReviewsFibrolamellar Carcinoma: Diagnosis and Diagnostic PitfallsGraham, Rondell P. MBBS; Torbenson, Michael S. MDAuthor Information From the Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN. Reprints: Michael S. Torbenson, MD, Division of Anatomic Pathology, Mayo Clinic, 200 First St SW, Rochester, MN 55905. E-mail: Torbenson.firstname.lastname@example.org. The authors have no funding or conflicts to declare. Pathology Case Reviews: November/December 2014 - Volume 19 - Issue 6 - p 309-315 doi: 10.1097/PCR.0000000000000063 Buy Metrics Abstract Fibrolamellar carcinomas are a unique primary liver cancer that most commonly occur in teenaged individuals and young adults. They are not associated with chronic liver disease, and their etiology remains a mystery. The most important prognostic feature is tumor resectability. Overall, fibrolamellar carcinomas have a similar prognosis to that of typical hepatocellular carcinomas, after controlling for age and background liver disease. A diagnosis can be made only by histological findings. Distinctive histological features include large eosinophilic tumor cells, prominent tumor nucleoli, and extensive intratumoral fibrosis. The hematoxylin-eosin impression of fibrolamellar carcinoma can be confirmed with CK7 and CD68 immunostains. There are numerous diagnostic pitfalls, which are further discussed in this review. There is no effective chemotherapy to date, but molecular studies have identified several potential targets including epidermal growth factor receptor, mammalian target of rapamycin, and fibroblast growth factor receptor 1 pathways. © 2014 by Lippincott Williams & Wilkins.