Improvement of Al18 F-PSMA-BCH preparation and its preliminary imaging study / 中华核医学与分子影像杂志

ABSTRACT

Objective To optimize the radiolabeling of prostate specific membrane antigen (PSMA)-targeted probe Al18 F-PSMA-BCH (Beijing Cancer Hospital) and to evaluate its potential for clinical trial and translation. Methods The mixture of PSMA-BCH, AlCl3 , potassium biphthalate and no-carrier loaded 18F- was reacted at 110 ℃ for 15 min, then purified by Sep-Pak Light C18 column and filtered through 0.22 μm sterile filter to obtain Al18 F-PSMA-BCH. The radiolabeled yield and radiochemical purity were determined. Al18 F-PSMA-BCH PET/ CT imaging was performed on 5 healthy volunteers (age (68±7) years) for bio-distribution and radiation dosimetry estimate and on 1 patient (65 years) with recurrent prostate cancer. Re-sults The non-decay-corrected radiochemical yield of Al18F-PSMA-BCH was (38. 0±3.5)％ with the radiochem-ical purity >99％ and the specific activity of (16.4±4.4) MBq/ nmol. Al18 F-PSMA-BCH was stable in saline at room temperature. In healthy volunteers, radioactivity was mainly accumulated in the bladder, kidneys, lacrimal glands, parotid glands and submandibular glands, of which kidneys were the most critical organs with the dosim-etry of (152.89±33.43) μGy/ MBq, while bones showed lower uptake ((11.10±1.23) μGy/ MBq) than most or-gans. The effective dose of whole body was (0.0135 ±0.0025) mSv/ MBq. Multiple bone metastases were ob-served by Al18F-PSMA-BCH PET/ CT imaging in a patient with recurrent prostate cancer. Conclusions Al18 F-PSMA-BCH prepared with the pH controller of potassium biphthalate holds the potential for the diagnosis, staging and monitoring recurrence of prostate cancer.