P1907 - Metastatic Sarcomatoid Hepatocellular Carcinoma After Orthotopic Liver Transplantation

Pratik Patel, MD¹, Jon Finan, MD, PhD², Nyingi Kemmer, MD, MSc, MPH³, Saurabh Agrawal, MD^3
1University of South Florida, Titusville, FL; ²Tampa General Hospital, Tampa, FL; ³Tampa General Medical Group, Tampa, FL

Introduction: Sarcomatoid Hepatocellular Carcinoma (S-HCC) is a rare subtype of Hepatocellular Carcinoma (HCC) that represents approximately 2-4% of all HCC. Sarcomatoid conversion of traditional HCC has been associated with repeated locoregional therapy (LRT), such as transarterial chemoembolization (TACE), radiofrequency ablation (RFA) and percutaneous ethanol injection. We present a rare case of metastatic S-HCC after orthotopic liver transplantation (OLT) for HCC that was previously treated with multiple sessions of TACE.

Case Description/Methods: This is a 64-year-old female with history of cirrhosis related to hepatitis C, complicated by 3.5 cm OPTN 5B HCC within segment 8 of the liver. Initial AFP was 5000. The lesion was treated with TACE x 3 over a time frame of 3 months. Repeat imaging revealed recurrence of HCC with two < 3cm lesions in segment 7. These lesions were treated with TACE of the superior branch of the right hepatic artery. She obtained MELD exception points and underwent OLT one month later. Pathology from the explanted liver revealed a 6.8 x 6.3 x 4.3cm S-HCC with large vessel invasion and no treatment effect from downstaging. Lymph nodes were negative for metastatic tumor. Surveillance imaging for high-risk S-HCC on explant three months later revealed no suspicious liver lesions, however there were multiple bilateral pulmonary nodules, the largest measuring 2.7 x 1.9 cm. The most accessible lung mass was biopsied and pathology confirmed metastatic S-HCC. She was referred to oncology for further management.

Discussion: Sarcomatoid Hepatocellular Carcinoma is a rare variant of HCC that is histologically characterized by spindle cells and bizarre giant cells. S-HCC is more aggressive than traditional HCC with high rates of recurrence and metastasis. Transformation of traditional HCC to S-HCC after multiple treatments with LRT is well documented in literature. Pathophysiology of this conversion is still not well understood. Our patient received multiple treatments with TACE with surveillance imaging prior to transplant revealing no evidence of tumor recurrence or residual disease. This highlights a possible concern that the typical imaging characteristics of HCC may not hold true for S-HCC. To date there are a few studies comparing imaging characteristics of S-HCC to traditional HCC, however there are no current guidelines for diagnosing S-HCC simply based on imaging. Developing a guideline may help prevent morbidity and mortality in patients undergoing LRT while actively listed for OLT.



Disclosures:


Pratik Patel, MD¹, Jon Finan, MD, PhD², Nyingi Kemmer, MD, MSc, MPH³, Saurabh Agrawal, MD³. P1907 - Metastatic Sarcomatoid Hepatocellular Carcinoma After Orthotopic Liver Transplantation, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.