PSMA-PET similar to MRI, superior to CT for liver cancer diagnosis: Study

"PSMA PET/CT can serve as a confirmatory test when findings from conventional imaging are equivocal, allowing for earlier diagnosis and improved management of liver cancer," the researchers wrote in their study published in the MDPI journal Tomography.

Hepatocellular carcinoma is the most frequently occurring primary liver malignancy, the third leading cause of cancer death, with an overall increasing incidence and 18% 5-year survival. Earlier diagnosis of recurrent or new HCC in at-risk patients improves long-term disease-free survival and provides the best opportunity for effective treatment.

Prostate-specific membrane antigen is expressed by approximately 90% of HCC in small case series and in-vitro studies. PSMA PET/CT has the potential as an imaging agent for detecting hepatocellular carcinoma, including early diagnosis and monitoring for recurrence following surgical resection. Considering this, Veronica Chi Ken Wong from The University of Sydney in Sydney, Australia, and colleagues aimed to compare PSMA PET to standard surveillance imaging in HCC detection.

For this purpose, the researchers prospectively recruited patients with suspected or treated hepatocellular carcinoma from a tertiary hospital outpatient clinic. A PSMA PET/CT was performed in addition to routine surveillance imaging as recommended by the multidisciplinary team. Clinical and imaging characteristics were compared over a follow-up period of up to 12 months.

Key findings of the study include:

• In a cohort of 19 patients with known HCC or suspected recurrent HCC, the efficacy of PSMA PET/CT was similar to MRI for the detection of hepatocellular carcinoma, with a sensitivity of 91% and a specificity of 70% and a sensitivity of 87% and a specificity of 73% for PSMA PET/CT and MRI, respectively.
• PSMA PET/CT had a higher negative predictive value of 90%.

To conclude, PSMA is shown to have promising equivalence in performance in the relatively sizeable single-centre study, and its role should be further evaluated in multi-centre prospective trials. The study showed PSMA PET/CT to be just as sensitive as MRI in detecting HCC and superior to CT.

"Future studies are underway, including phase 2 studies that will examine the utility of PSMA PET/MRI as a combined imaging modality and may continue to shed more light on the use of PSMA PET for HCC detection," the researchers wrote in their study. "PSMA-positivity may provide options for theranostic approaches using molecular markers linked with radionuclide therapies."

Reference:

Wong, V.C.K.; Yip, J.; Fragomeli, V.; Weltman, M.; Loh, H.; Le, K.; Nguyen, D.; Bui, C.; Mansberg, R. Comparison between PSMA PET/CT and MRI for Characterizing Hepatocellular carcinoma: A Real-World Study. Tomography 2023, 9, 130-138. https://doi.org/10.3390/tomography9010011