A case of well-differentiated hepatocellular carcinoma identified on gallium-68 prostate-specific membrane antigen positron emission tomography/computed tomography

Abstract

Prostate-specific membrane antigen (PSMA) is a glycosylated type-II transmembrane protein highly expressed in certain tumor cells. To the best of our knowledge, this is the first case reported of an isolated well-differentiated hepatocellular carcinoma (HCC) strongly suspected on gallium-68 ( 68 Ga)-PSMA positron emission tomography/computed tomography (PET/CT), which was not well characterized both on magnetic resonance imaging (MRI) liver with Primovist as well as fluorine-18 ( 18 F)-choline PET/CT. Our patient had previous prostate cancer and previously was imaged using 18 F-choline PET/CT. The last scan showed an indeterminate segment VII hypodensity which was not significantly choline-avid. The lesion was initially stable on serial MRI scans but then showed growth from 1.0 to 1.5 cm. 68 Ga-PSMA PET/CT was performed. The lesion was intensely tracer-avid. This was surgically excised and histology confirmed the presence of well-differentiated HCC. Well-differentiated HCC can be optimally imaged using 68 Ga-PSMA PET/CT and further prospective studies are needed to look into the potential of this imaging modality.

Prostate-specific membrane antigen-expressing hepatic lesion: Metastatic or hepatocellular carcinoma

“…[8] In the case described by Huang et al, both AFP and PSA were within normal range and biopsy showed an encapsulated hepatocellular lesion in a cirrhotic liver. [9] In our case, the patient had raised PSA and normal AFP level in the blood. No PSMA-expressing lesion attributable to prostatic cancer was demonstrated in our case.…”

Cancers and Benign Processes on 68Ga PSMA PET-CT Imaging Other than Prostate Cancer

“…68 Ga PSMA ligand uptake in thyroid gland, lung metastasis, gastric and colonic malignancies, RCC, neuroendocrine tumor, glioma, breast cancer, gynecological malignancies, and HCC was reported in literature. 5 9 10 11 12 13 14 15 16 17 Parathyroid adenoma was included in the differential diagnosis of focal tracer uptake in a report by Pfob et al 18 In the current study, the most common 68 Ga PSMA ligand avid malignancy was lung adenocarcinoma. In addition, malignancies such as gastric adenocarcinoma, multiple myeloma, lung neuroendocrine tumor, urothelial carcinoma, HCC, colon adenocarcinoma, NSCLC showed 68 Ga PSMA ligand avidity.…”

Different Appearances of 3 Malignancies in 68Ga-PSMA-11 Versus 18F-FDG PET/CT

“…5 Only a few recent case series have described PSMA uptake in primary HCC using various PSMA ligands. [6][7][8] In contrast, immunohistochemical staining in 103 cases indicated promising results for in vivo utilization of 68 Ga-PSMA PET/CT in HCC. 9 Another immunohistochemistry analysis showed high PSMA staining of the endothelial cell lining of vessels penetrated by HCC tumor cells.…”

“…However, a higher tumor-to-liver FDG ratio has been described in presence of extrahepatic metastasis 5 . Only a few recent case series have described PSMA uptake in primary HCC using various PSMA ligands 6–8 . In contrast, immunohistochemical staining in 103 cases indicated promising results for in vivo utilization of 68 Ga-PSMA PET/CT in HCC 9 .…”