A prospective study of 68Ga-PSMA PET/CT imaging of HCC as diagnosed on conventional imaging to evaluate for potential 177Lu-PSMA therapy.

Abstract

Objective: PSMA expression is seen in many solid tumours in addition to prostate cancer and several studies and case reports have shown PSMA expression and ⁶⁸Ga-PSMA imaging of hepatocellular carcinoma (HCC). Our prospective study evaluates the role of ⁶⁸Ga-PSMA in HCC patients and compares it to conventional imaging (CE-CT/MRI).

Methods: Patients with radiologically and/or histopathologically confirmed HCC were included and all had undergone serum alpha-fetoprotein (S.AFP) assessment as well as CE-CT/MRI prior to PSMA PET/CT. Acquired whole-body PET/CTs were analysed both visually and quantitatively by two experienced nuclear medicine physicians.

Results: Forty-one (41) patients (36 male; 5 female) with known HCC and a mean age of 53.9 ± 10.9 years underwent ⁶⁸Ga-PSMA PET/CT. All patients had lesions on conventional imaging but only 38/41 patients showed ⁶⁸Ga-PSMA uptake. Conventional imaging revealed 18 patients with single lesions, all of which were tracer avid. Twenty-three (23) of 41 patients had multifocal (> 2) hepatic lesions on CE-CT/MRI of which 3 patients showed no ⁶⁸Ga-PSMA uptake, 7 showed tracer uptake in a single lesion only and 13 patients had multifocal tracer avid lesions. There was no correlation observed between S. AFP level and tumour SUV_max on ⁶⁸Ga-PSMA PET/CT.

Conclusion: ⁶⁸Ga-PSMA PET/CT imaging of HCC may complement conventional imaging and identify patients for potential theranostic intervention.