P2449 - Incidental Neuroendocrine Tumors on Liver Explants

Divya Rayapati, MD¹, Jessica Lin, MD, MBA¹, Jacqueline E. Birkness-Gartman, MD², Kiyoko Oshima, MD, PhD³, Haneyeh Shahbazian, MD⁴, Ihab RK. Kamel, MD, PhD¹, Alia S.. Dadabhai, MD⁵, Ruhail Kohli, MBBCh⁴, Kiara Tulla, MD⁶, Elizabeth King, MD⁷, Benjamin Philosophe, MD, PhD⁶, Andrew M. Cameron, MD², Shane Ottmann, MD¹, Ahmet Ö. Gurakar, MD^8
1Johns Hopkins Hospital, Baltimore, MD; ²Johns Hopkins University School of Medicine, Baltimore, MD; ³Johns Hopkins University School of medicine, Baltimore, MD; ⁴Johns Hopkins University, Baltimore, MD; ⁵Johns Hopkins University, Washington, DC; ⁶Johns Hopkins, Baltimore, MD; ⁷Johns Hopkins University, Ellicott City, MD; ⁸Johns Hopkins, Lutherville, MD

Introduction: Neuroendocrine tumors (NETs), which account for 0.5% of newly diagnosed malignancies, most commonly metastasize to the liver, irrespective of the primary site. Patients undergoing deceased donor liver transplant (DDLT) evaluation receive extensive liver imaging that may reveal incidental hepatic lesions. These lesions are sometimes misdiagnosed as hepatocellular carcinoma (HCC) rather than NETs. We report two cases of patients who underwent DDLT for non-alcoholic steatohepatitis (NASH) and had hepatic lesions on pre-transplant imaging presumed to be HCC. Both lesions were revealed to be NETs upon histopathologic review of liver explants.

Case Description/Methods: Case 1:
A 65-year-old woman with decompensated cirrhosis had a 0.7 cm enhancing lesion in the right hepatic segment 6 with significant iron deposition in the liver on magnetic resonance imaging (MRI). Alpha fetoprotein (AFP) was 4.5 ng/mL, and hemochromatosis mutation was negative. She underwent DDLT, and explant pathology of the liver lesion showed well-differentiated NET (WDNET). Chromogranin A was elevated to 2253 ng/mL after transplant. A primary source of NET was not identified on post-transplant imaging.

Case 2:
A 70-year-old woman with decompensated cirrhosis had a 1.1 cm arterially enhancing lesion in segment 8 on MRI. The lesion was discussed at tumor board and characterized as solitary lesion HCC with normal AFP at 1.6 ng/mL. She underwent DDLT, and liver explant pathology of the lesion showed 1.2 cm WDNET with central necrosis. Octreotide PET/CT scan showed likely primary small bowel malignancy with foci of uptake within small bowel loops. She underwent small bowel resection 5 months post-transplant. Her chromogranin A was elevated to 5117 ng/mL initially after transplant, and decreased to 2244 ng/mL after small bowel resection.

Both women remain well at 31 and 13 months post-transplant, respectively.

Discussion: These are some of the first cases reported of incidental findings of NET in the explanted liver. While liver transplantation may be part of management of metastatic NET to the liver, both patients had known MRI abnormalities attributed to possible HCC. Thus, for patients with obscure imaging findings, particularly during the pre-transplant evaluation, we suggest maintaining NET on the differential and considering further evaluation with chromogranin A as the biomarker. This may be especially important for normal AFP cases. Somatostatin analog studies can also be considered if chromogranin level is elevated.



Disclosures:


Divya Rayapati, MD¹, Jessica Lin, MD, MBA¹, Jacqueline E. Birkness-Gartman, MD², Kiyoko Oshima, MD, PhD³, Haneyeh Shahbazian, MD⁴, Ihab RK. Kamel, MD, PhD¹, Alia S.. Dadabhai, MD⁵, Ruhail Kohli, MBBCh⁴, Kiara Tulla, MD⁶, Elizabeth King, MD⁷, Benjamin Philosophe, MD, PhD⁶, Andrew M. Cameron, MD², Shane Ottmann, MD¹, Ahmet Ö. Gurakar, MD⁸. P2449 - Incidental Neuroendocrine Tumors on Liver Explants, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.