Primary Liver Carcinomas: Challenges, Tools, and Diagnostic Considerations

Primary liver carcinomas (PLCs), including hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA), are the most common categories of adult primary liver neoplasm with major clinical and surgical implications; however, their diagnosis is fraught with potential pitfalls for the surgical pathologist. This presentation examines the general morphologic features of HCC and iCCA as well as uses and limitations of ancillary stains used to support their diagnosis. A basic approach and discussion of diagnostic challenges is also presented for the common scenario of adenocarcinoma in a liver mass biopsy, as well as for particularly challenging cases of poorly differentiated primary liver carcinomas (PD-PLCs). The potential role for genomic analysis in the categorization of PD-PLCs is discussed, along with insights gained from next generation sequencing of both PD-PLCs and their equally confounding counterpart, combined hepatocellular cholangiocarcinomas.

Originally published on May 4, 2026

Lecture Presenter

Alexander Kikuchi, MD, PhD Assistant Professor (Clinical) Spencer Fox Eccles School of Medicine at the University of Utah Pathologist ARUP Laboratories

Dr. Alexander Kikuchi is a medical director at ARUP Laboratories, and an associate professor (clinical) at the Spencer Fox Eccles School of Medicine at the University of Utah. He received his medical and doctorate degrees from the University of Pittsburgh School of Medicine and did his residency in pathology at the University of California San Francisco. He completed fellowships in gastrointestinal and hepatobiliary pathology, and surgical pathology at the University of California San Francisco. Dr. Kikuchi is board certified in anatomic pathology by the American Board of Pathology. He is a member of the Hans Popper Hepatopathology Society, the Rodger C. Haggit Gastrointestinal Pathology Society, and the Pancreatobiliary Pathology Society. He has received awards from the Hans Popper Hepatopathology Society Best Trainee Abstract Award (1st place) at the 2022 USCAP Meeting, the Robert E. Lee, MD, Award for Excellence in Anatomic Pathology (University of Pittsburgh School of Medicine, 2019), Presidential Poster Award at the 2017 AASLD Conference, Summa Cum Laude (University of Southern California, 2010), and a Renaissance Scholar (University of Southern California, 2010). Dr. Kikuchi’s research interests include histopathologic and molecular classification of primary liver neoplasms, chronic liver injury, hepatic fibrosis, and hepatic carcinogenesis.

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Objectives

After this presentation, participants will be able to:

• Describe the general morphologic features and uses/limitations of ancillary stains used to identify HCC
• Describe the general morphologic features and uses/limitations of ancillary stains used to identify iCCA
• Acknowledge the role of immunohistochemistry and albumin in situ hybridization (ISH) in the workup of adenocarcinoma in a liver biopsy
• Observe the challenges in differentiating HCC and iCCA in PD-PLC cases, and the potential role of genomic analysis in evaluating these tumors

Sponsored by:

Spencer Fox Eccles School of Medicine at the University of Utah, Department of Pathology,
and ARUP Laboratories