A single centre pilot experience with ¹⁸F-JK-PSMA-7 PET-CT in the staging of prostate cancer

Background: The sensitivity and specificity of bone scintigraphy and thoraco-abdominopelvic CT scans traditionally used for the staging of prostate cancer don't meet clinical requirements. In 2020 ¹⁸F-JK-PSMA-7 positron emission tomography-computed tomography (PET-CT) became available in our country for routine clinical diagnostics.

Methods: As part of our self-assessment, we retrospectively analysed the results of 24 PSMA PET-CTs realised for our patients up to 31 December 2020.

Results: The indication of the examination was biochemical recurrence after radical prostatectomy (prostate specific antigen (PSA) >0.2 ng/mL) for 16 patients and primary staging (PSA range: 5.2–70 ng/mL) for 8 patients. Biochemical recurrence was related to local relapse in 2 cases, regional lymph node involvement in 5 cases, oligo- and multi-metastatic spread in 1 and 3 cases respectively. 5 patients had no detectable lesion. Patients with PSA <1 ng/mL showed no extrapelvic enhancement. At primary staging 3 patients presented distant metastases. There was no correlation between PSA level and disease extent. In total PSMA PET-CT results changed the treatment strategy for 7 patients.

Conclusions: ¹⁸F-JK-PSMA-7 PET-CT is a useful diagnostic tool. The examination can lead to change the treatment decision at primary staging as well as at biochemical recurrence. The results of this pilot study may support the strategy that patients with biochemical recurrence following radical prostatectomy receive salvage radiotherapy to the prostate bed and the pelvic lymphatic regions without any imaging examination when PSA <1 ng/mL.

Prostate cancer; PSMA PET-CT; Biochemical relapse; Therapy optimisation

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