New insights in the paradigm of upregulation of tumoral PSMA expression by androgen receptor blockade: Enzalutamide induces PSMA upregulation in castration-resistant prostate cancer even in patients having previously progressed on enzalutamide.
Eur J Nucl Med Mol Imaging
; 47(3): 687-694, 2020 03.
Article
em En
| MEDLINE
| ID: mdl-31901103
ABSTRACT
PURPOSE:
There is preliminary evidence for prostate-specific membrane antigen (PSMA) upregulation effects of androgen receptor blockade in prostate cancer. In an attempt to find the best condition for PSMA radioligand therapy in metastatic castration-resistant prostate cancer (mCRPC) patients, we evaluated the effect of oral enzalutamide in patients, predominantly having previously progressed on enzalutamide treatment.METHODS:
Ten patients with advanced mCRPC scheduled for PSMA radioligand therapy were examined with 68Ga-PSMA-11 PET/CT before and after a mean of 11.8 days of enzalutamide 160 mg/day. Imaging results were compared using total PSMA tumor burden quantification. We assessed whole-body total lesion PSMA (TLP), defined as SUVmean × tumor volume and calculated TLP-to-liver ratio (TLP-LR), TLP-to-parotid gland ratio (TLP-PR), and TLP-to-kidney ratio (TLP-KR).RESULTS:
The mean (median) increase of TLP-LR, TLP-PR, and TLP-KR in the cohort was 49.3% (38.8%), 45.1% (23.5%), and 54.9% (37.6%), respectively. These increases were statistically significant (p = 0.002, p = 0.014, and p = 0.014), while PSA values did not change significantly (p = 0.846). Seven of the 10 patients had previously undergone enzalutamide treatment with eventual progression, formally classified as treatment failure. No side effects were noted in the short term.CONCLUSIONS:
Our results suggest that enzalutamide could be considered as a PSMA radioligand treatment enhancing primer medication, which may increase PSMA expression by a dimension of 50% in mCRPC. The effect was shown even in patients having previously failed enzalutamide treatment for arrest of progression in the mCRPC setting. Our observation deserves evaluation in a prospective setting.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Neoplasias de Próstata Resistentes à Castração
Tipo de estudo:
Observational_studies
Limite:
Humans
/
Male
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article