PSMA-ligand PET allows a more accurate therapeutic response evaluation of bone metastases in prostate cancer compared to computed tomography

Abstract

A patient with bone metastases of prostate cancer was referred for ⁶⁸Ga-PSMA-11 PET/CT. Compared to a ⁶⁸Ga-PSMA-11 PET/CT four months previously, the CT-component of the current PET/CT showed morphological progress in all lesions despite continuous therapy with docetaxel and denosumab. Contrarily, the PET-component showed a reduction of tracer-uptake, which correlated with PSA decrease between the two PET/CT-scans (16.2 ng/ml vs. 3.1 ng/ml). This case highlights ⁶⁸Ga-PSMA-11 PET/CT as a promising tool for therapy monitoring of prostate cancer and could serve as a basis for a novel monitoring strategy. Volume progress shown by CT must not be classified as tumor progress, but as bone remodeling following effective therapy.

Key words

⁶⁸Ga–PSMA-11 - PSMA - PET/CT - bone metastases - prostate cancer - therapy monitoring

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