68Ga-P16-093 and 68Ga-PSMA-11 PET/CT Imaging in the Same Group of Primary Prostate Cancer Patients

A Pilot Comparison of 68Ga-P16-093 and 68Ga-PSMA-11 in the Same Group of Primary Prostate Cancer Patients

Prostate-specific membrane antigen (PSMA)-targeted PET imaging with 68Ga-labeled compounds is able to provide superior sensitivity and specificity to detect primary prostate tumor and its metastases, like the most widely studied 68Ga-PSMA-11. This pilot study was evaluate the diagnostic performance of 68Ga-P16-093, a novel radiopharmaceutical targeting PSMA, which was compared with 68Ga-PSMA-11 in the same group of primary prostate cancer patients.

Prostate cancer (PC) is one of the most common malignancies worldwide in men, with persistently high numbers dying from this disease. Due to low levels of glycolysis in prostate cancer cell, the uses of 18F-FDG PET/CT to detect prostate cancer and its metastases are limited. Prostate specific membrane antigen (PSMA), as known as folate hydrolase I or glutamate carboxypeptidase II, is overexpressed on the cells of prostatic adenocarcinoma. Various low molecular weight radiopharmaceuticals targeting PSMA such as PSMA-11, PSMA-617 for 68Ga-labeling have been developed. 68Ga-PSMA PET/CT has demonstrated desirable sensitivity and specificity in the detection of prostate cancer lesions, which can find many micro lesions that cannot be identified by CT, MRI and bone scan. 68Ga-P16-093, a novel radiopharmaceutical modified based on 68Ga-PSMA-11, with the urea fragment of a conjugate that employs the HBED-CC chelator for labeling with 68Ga(III). The HBED-based chelating ligand binds the 68Ga3+ ion with high affinity in a pseudo-octahedral N2O4 coordination sphere by its two phenolate O, two amino-acetate carboxylate O, and two amino N donor atoms. This pilot study was prospectively designed to evaluate the diagnostic performance of 68Ga-P16-093 compared with 68Ga-PSMA-11 in the same group of primary prostate cancer patients.

Patients of Prostate cancer PET/CT imaging: In two consecutive days, each patient underwent whole-body PET/CT scan after intravenous administration of 68Ga-P16-093 and 68Ga-PSMA-11, respectively.

Intravenous injection of 68Ga-P16-093 with the dosage of 1.8-2.2 MBq (0.05-0.06 mCi)/kg. Tracer doses of 68Ga-P16-093 will be used to image lesions of prostate cancer by PET/CT.

Intravenous injection of 68Ga-PSMA-11 with the dosage of 1.8-2.2 MBq (0.05-0.06 mCi)/kg. Tracer doses of 68Ga-PSMA-11 will be used to image lesions of prostate cancer by PET/CT.

Inclusion Criteria: histologically confirmed untreated primary prostate cancer patients; 68Ga-PSMA-11 and 68Ga-P16-093 PET/CT within a week; signed written consent. Exclusion Criteria: known allergy against PSMA; any medical condition that in the opinion of the investigator may significantly interfere with study compliance.