Parameters predicting [18F]PSMA-1007 scan positivity and type and number of detected lesions in patients with biochemical recurrence of prostate cancer

Abstract

Background Detection of the site of recurrence using PSMA-PET/CT is important to guide treatment in patients with biochemical recurrence of prostate cancer (PCa). The aim of this study was to evaluate the positivity rate of [18F]PSMA-1007-PET/CT in patients with biochemically recurrent PCa and identify parameters that predict scan positivity as well as the type and number of detected lesions. This monocentric retrospective study included 137 PCa patients with biochemical recurrence who underwent one or more [18F]PSMA-1007-PET/CT scans between August 2018 and June 2019. PET-positive malignant lesions were classified as local recurrence, lymph node (LN), bone or soft tissue lesions. The association between biochemical/paraclinical parameters, as PSA value, PSA doubling time, PSA velocity, Gleason score (GS) and androgen deprivation therapy (ADT), and scan positivity as well as type and number of detected lesions was evaluated using logistic regression analysis (binary outcomes) and Poisson models (count-type outcomes). Results We included 175 [18F]PSMA-1007-PET/CT scans after radical prostatectomy (78%), external beam radiation therapy (8.8%), ADT (7.3%), brachytherapy (5.1%) and high intensity focused ultrasound (0.7%) as primary treatment (median PSA value 1.6 ng/ml). Positivity rate was 80%. PSA value and PSA velocity were significant predictors of scan positivity as well as of the presence of bone and soft tissue lesions and number of bone, LN and soft tissue lesions, both in uni- and/or multivariable analysis. Multivariable analysis also showed prior ADT as predictor of bone and soft tissue lesions, GS as predictor of the number of bone lesions and ongoing ADT as predictor of the number of LN lesions. Conclusion [18F]PSMA-1007-PET/CT showed a high positivity rate in patients with biochemically recurrent PCa. PSA value and PSA velocity were significant predictors of scan positivity as well as of the presence and number of bone and soft tissue lesions and the number of LN lesions. Our findings can guide clinicians in optimal patient selection for [18F]PSMA-1007-PET/CT and support further research leading to the development of a prediction nomogram.

18F-PSMA-1007 PET in Biochemical Recurrent Prostate Cancer: An Updated Meta-Analysis

“…Reviewing titles and abstracts, 83 records were excluded: 70 because not in the field of interest of this review, 7 as reviews, editorials, or letters, and 6 as case reports. Fifteen articles were selected, and their full-text version was retrieved [ 22 – 36 ]. No additional studies were found screening the references of these articles.…”

“…Three articles were excluded from the meta-analysis for possible patient data overlap [ 24 , 28 , 34 ] and two for insufficient data to calculate the DR on a per scan-based analysis [ 32 , 36 ]. Finally, 10 articles were included in the quantitative analysis (meta-analysis) [ 22 , 23 , 25 – 27 , 29 – 31 , 33 , 35 ]. Tables 1 – 3 show the characteristics of the selected studies and their main findings.…”

“…Through the literature search using the selected bibliographic databases, 15 full-text articles (853 BRPCa patients) were selected [ 22 – 36 ]. All the eligible articles were recently published; different countries were represented; most of the studies were retrospective (73%) or monocentric (87%), and there were no prospective multicentre studies.…”

“…First of all, no significant adverse effects/side effects after the injection of 18 F-PSMA-1007 were reported in the included studies [ 22 – 36 ].…”

“…Overall, a good DR of 18 F-PSMA-1007 PET/CT or PET/MRI in BRPCa patients was described [ 22 – 36 ]. The DR of 18 F-PSMA-1007 PET/CT or PET/MRI was dependent on PSA serum values: in other words, higher PSA values were associated with a higher DR, with excellent DR for PSA values >1 ng/ml [ 24 , 25 , 29 , 31 , 33 , 35 ].…”