Antihormonal-Treatment Status Affects 68Ga-PSMA-HBED-CC PET Biodistribution in Patients with Prostate Cancer.

Androgen deprivation therapy (ADT) is known to influence the prostate-specific membrane antigen (PSMA) expression of prostate cancer, potentially complicating the interpretation of PSMA ligand PET findings and affecting PSMA radioligand therapy. However, the impact of ADT on PSMA ligand biodistribution in nontumorous organs is not well understood. Methods: Men (n = 112) with histologically proven prostate cancer who underwent 68Ga-PSMA-HBED-CC (68Ga-PSMA-11) PET/CT between November 2015 and July 2021 at the Medical University Vienna with known ADT status were retrospectively recruited. Fifty-six patients were on gonadotropin-releasing hormone-interfering ADT at the time of imaging (ADT group), whereas 56 patients with no history of ADT served as a control group. Physiologically PSMA-expressing organs (salivary glands, kidneys, liver, and spleen) were delineated, and their uptake was compared according to their data distributions. Multivariate regression analysis assessed the relationship between renal, hepatic, splenic, and salivary gland uptake and the explanatory variables metabolic tumor volume, glomerular filtration rate, and ADT status. Results: ADT was associated with lower levels of PSMA uptake in the kidneys (SUVmean: Δ[ADT - control] = -7.89; 95% CI, -10.73 to -5.04; P < 0.001), liver (SUVpeak: Δ[ADT - control] = -2.3; 95% CI, -5.72 to -0.93; P = 0.003), spleen (SUVpeak: Δ[ADT - control] = -1.27; 95% CI, -3.61 to -0.16; P = 0.033), and salivary glands (SUVmean: Δ[ADT - control] = -1.04; 95% CI, -2.48 to -0.13; P = 0.027). In a multivariate analysis, ADT was found to be associated with lower renal (SUVmean: ß = -7.95; 95% CI, -11.06 to -4.84; P < 0.0001), hepatic (SUVpeak: ß = -7.85; 95% CI, -11.78 to -3.91; P < 0.0001), splenic (SUVpeak: ß = -5.83; 95% CI, -9.95 to -1.7; P = 0.006), and salivary gland (SUVmean: ß = -1.47; 95% CI, -2.76 to -0.17; P = 0.027) uptake. A higher glomerular filtration rate was associated with a higher renal SUVmean (ß = 0.16; 95% CI, 0.05 to 0.26; P = 0.0034). Conclusion: These findings suggest that ADT systemically modulates PSMA expression, which may have implications for treatment-optimizing and side-effect-minimizing strategies for PSMA radioligand therapies, particularly those using more potent 225Ac-labeled PSMA conjugates.

Quality of life in patients with metastatic prostate cancer following treatment with cabazitaxel versus abiraterone or enzalutamide (CARD): an analysis of a randomised, multicentre, open-label, phase 4 study.

BACKGROUND: In the CARD study, cabazitaxel significantly improved radiographic progression-free survival and overall survival versus abiraterone or enzalutamide in patients with metastatic castration-resistant prostate cancer previously treated with docetaxel and the alternative androgen signalling-targeted inhibitor. Here, we report the quality-of-life outcomes from the CARD study. METHODS: CARD was a randomised, multicentre, open-label, phase 4 study involving 62 clinical sites across 13 European countries. Patients (aged ≥18 years, Eastern Cooperative Oncology Group (ECOG) performance status ≤2) with confirmed metastatic castration-resistant prostate cancer were randomly assigned (1:1) by means of an interactive voice-web response system to receive cabazitaxel (25 mg/m2 intravenously every 3 weeks, 10 mg daily prednisone, and granulocyte colony-stimulating factor) versus abiraterone (1000 mg orally once daily plus 5 mg prednisone twice daily) or enzalutamide (160 mg orally daily). Stratification factors were ECOG performance status, time to disease progression on the previous androgen signalling-targeted inhibitor, and timing of the previous androgen signalling-targeted inhibitor. The primary endpoint was radiographic progression-free survival; here, we present more detailed analyses of pain (assessed using item 3 on the Brief Pain Inventory-Short Form [BPI-SF]) and symptomatic skeletal events, alongside preplanned patient-reported outcomes, assessed using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire and the EuroQoL-5 dimensions, 5 level scale (EQ-5D-5L). Efficacy analyses were done in the intention-to-treat population. Pain response was analysed in the intention-to-treat population with baseline and at least one post-baseline assessment of BPI-SF item 3, and patient-reported outcomes (PROs) were analysed in the intention-to-treat population with baseline and at least one post-baseline assessment of either FACT-P or EQ-5D-5L (PRO population). Analyses of skeletal-related events were also done in the intention-to-treat population. The CARD study is registered with ClinicalTrials.gov, NCT02485691, and is no longer enrolling. FINDINGS: Between Nov 17, 2015, and Nov 28, 2018, of 303 patients screened, 255 were randomly assigned to cabazitaxel (n=129) or abiraterone or enzalutamide (n=126). Median follow-up was 9·2 months (IQR 5·6-13·1). Pain response was observed in 51 (46%) of 111 patients with cabazitaxel and 21 (19%) of 109 patients with abiraterone or enzalutamide (p<0·0001). Median time to pain progression was not estimable (NE; 95% CI NE-NE) with cabazitaxel and 8·5 months (4·9-NE) with abiraterone or enzalutamide (hazard ratio [HR] 0·55, 95% CI 0·32-0·97; log-rank p=0·035). Median time to symptomatic skeletal events was NE (95% CI 20·0-NE) with cabazitaxel and 16·7 months (10·8-NE) with abiraterone or enzalutamide (HR 0·59, 95% CI 0·35-1·01; log-rank p=0·050). Median time to FACT-P total score deterioration was 14·8 months (95% CI 6·3-NE) with cabazitaxel and 8·9 months (6·3-NE) with abiraterone or enzalutamide (HR 0·72, 95% CI 0·44-1·20; log-rank p=0·21). There was a significant treatment effect seen in changes from baseline in EQ-5D-5L utility index score in favour of cabazitaxel over abiraterone or enzalutamide (p=0·030) but no difference between treatment groups for change from baseline in EQ-5D-5L visual analogue scale (p=0·060). INTERPRETATION: Since cabazitaxel improved pain response, time to pain progression, time to symptomatic skeletal events, and EQ-5D-5L utility index, clinicians and patients with metastatic castration-resistant prostate cancer can be reassured that cabazitaxel will not reduce quality of life when compared with treatment with a second androgen signalling-targeted inhibitor. FUNDING: Sanofi.

Response assessment using [68 Ga]Ga-PSMA ligand PET in patients undergoing systemic therapy for metastatic castration-resistant prostate cancer.

BACKGROUND: To assess which parameters of [68 Ga]Ga-PSMA-11 positron emission tomography (PSMA-PET) predict response to systemic therapies in metastatic (m) castration-resistant prostate cancer (CRPC). In addition, to investigate which of these factors are associated with overall survival (OS). METHODS: We retrospectively assessed the following PSMA-PET parameters in 43 patients before and after systemic therapies for mCRPC: PSMA total tumor volume (TTV), mean standardized uptake value (SUVmean), SUVmax, and SUVpeak. prostate-specific antigen (PSA) levels and PSMA-PET/CT(magnetic resonance imaging [MRI]) imaging were both performed within 8 weeks before and 6 weeks after systemic therapy. PSMA-PET and CT (MRI) images were reviewed according to the modified PET Response Criteria in Solid Tumors (PERCIST) and Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. Results were compared to PSA response. Univariable survival analyses were performed. RESULTS: Overall, 43 patients undergoing 67 systemic therapies were included (9 patients radium-223, 12 cabazitaxel, 22 docetaxel, 6 abiraterone, and 18 enzalutamide). Median serum PSA level before any therapy was 11.3 ng/mL (interquartile range [IQR] = 3.3, 30.1). Delta (d) PSA after systemic therapies was -41%, dTTV 10.5%, dSUVmean -7.5%, dSUVmax -13.3%, dSUVpeak -12%, and dRECIST -13.3%. Overall, 31 patients had dPSA response (46.3%), 12 stable disease (17.9%), and 24 progressive disease (35.8%). All observed PET parameters, as well as the RECIST evaluation, were significantly associated with PSA response (dTTV P = .003, dSUVmean P = .003, dSUVmax P = .011, dSUVpeak P < 0001, dRECIST P = .012), while RECIST assessment was applicable in 37 out of 67 patients (55.2%). Within a median follow-up of 33 months (IQR = 26, 38), 10 patients (23.3%) died of PC. On univariable survival analyses, neither the investigated PET parameters nor PSA level or RECIST criteria were associated with OS. CONCLUSION: PSMA-PET provides reliable parameters for prediction of response to systemic therapies for mCRPC. These parameters, if confirmed, could enhance RECIST criteria, specifically concerning its limitations for sclerotic bone lesions.

Prevalence and Prognostic Value of the Polymorphic Variant 1245A>C of HSD3B1 in Castration-resistant Prostate Cancer.

INTRODUCTION: The purpose of this study was to investigate the prevalence and prognostic value of the polymorphic variant (1245A>C), a single nucleotide polymorphism (SNP) of the HSD3B1 gene, in the tumors of patients with castration-resistant prostate cancer (CRPC). MATERIALS AND METHODS: We retrospectively evaluated 44 patients with CRPC who underwent palliative transurethral resection of the prostate. Genomic DNA was extracted from formalin-fixed and paraffin-embedded material, and 1245A>C SNP of the HSD3B1 gene was analyzed via Sanger sequencing. Cox regression analysis was used to assess the prognostic value of the respective SNP with time to progression as well as cancer-specific and overall survival in the subgroup of patients receiving second systemic treatment. RESULTS: The SNP was present in 20 patients (51.2%) who received second line systemic treatment additionally to androgen deprivation, of which 16 (80%) patients were heterozygous and 4 (20%) were homozygous. Correlation analysis revealed no association of the SNP with any clinical characteristics at initiation of second-line systemic treatment. Moreover, the presence of the variant (1245A>C) of HSD3B1 was not associated with any survival endpoint. CONCLUSIONS: The variant allele 1245C of the HSD3B1 gene is present in approximately one-half of patients with CRPC; however, it is not associated with oncologic outcomes. These findings, however, need to be interpreted with caution as the sample size is small. Further research on biomarkers is needed to help tailor clinical decision making in prostate cancer, especially in the increasingly complex therapeutic landscape of CRPC.

Hypothyroidism in patients with renal cell carcinoma: blessing or curse?

BACKGROUND: Sunitinib and sorafenib are tyrosine kinase inhibitors that have important antitumor activity in metastatic renal cell carcinoma (mRCC). Hypothyroidism constitutes a commonly reported side effect of both drugs, and particularly of sunitinib. The objective of this analysis was to investigate whether the occurrence of hypothyroidism during treatment with sunitinib and sorafenib affects the outcome of patients with mRCC. METHODS: Eighty-seven consecutive patients with mRCC who were to receive treatment with sunitinib or sorafenib were included in a prospective analysis. Thyroid function was assessed in each patient every 4 weeks during the first 2 months of treatment and every 2 to 4 months thereafter. Assessment included serum levels of thyroid-stimulating hormone (TSH), tri-iodthyronine (T3), and thyroxine (T4). Subclinical hypothyroidism was defined as an increase in TSH above the upper limit of normal (>3.77 µM/mL) with normal T3 and T4 levels. RESULTS: Subclinical hypothyroidism was evident in 5 patients at baseline and occurred in 30 patients (36.1%) within the first 2 months after treatment initiation. There was a statistically significant correlation between the occurrence of subclinical hypothyroidism during treatment and the rate of objective remission (hypothyroid patients vs euthyroid patients: 28.3% vs 3.3%, respectively; P < .001) and the median duration of survival (not reached vs 13.9 months, respectively; hazard ratio, 0.35; 95% confidence interval, 0.14-0.85; P = .016). In multivariate analysis, the development of subclinical hypothyroidism was identified as an independent predictor of survival (hazard ratio, 0.31; P = .014). CONCLUSIONS: The current results indicated that hypothyroidism may serve as a predictive marker of treatment outcome in patients with mRCC. Thus, the interpretation of hypothyroidism during treatment with sunitinib and sorafenib as an unwanted side effect should be reconsidered.

Response to sublethal heat treatment of prostatic tumor cells and of prostatic tumor infiltrating T-cells.

BACKGROUND: To investigate the possibilities offered by high intensity focused ultrasound (HIFU) in the field of tumor vaccination, we analyzed how prostatic cancer (CaP) cells react towards heat treatment and whether increased access to CaP cells by the immune system would be the result. METHODS: Heat/stress response of CaP cells in situ and of CaP cell lines was analyzed by immunohistochemistry, Western blotting, and Atlas array. A heat-induced change in immune recognition was analyzed functionally using human T-helper (Th)1 and Th2-cytokine release with tumor infiltrating T-lymphocytes (TIL) as responder and autologous CaP cells either heated or untreated as stimulator cells. RESULTS: Transcription of 68 out of 500 genes was upregulated by sublethal heat in LNCaP and PC3 cells. Significantly upregulated stress protein (SP) expression (HSP-72, -73, GRP-75, -78) was seen at the border zone of HIFU treatment. Remarkably, even untreated benign prostatic hyperplasia (BPH) specimens revealed relative overexpression of heat shock protein (HSP)-72, -73 and glucose regulated protein (GRP)-75, -78. Heated CaP cells increased Th1-cytokine (IL-2, IFN-gamma, TNF-alpha) release but decreased Th2-cytokine (IL-4, -5, -10) release of TIL. CONCLUSIONS: HIFU treatment may alter the presentation of prostate tissue and tumor antigens and this presentation is most likely stimulatory. HSP-72/73 overexpression in untreated BPH may suggest a mechanism by which BPH can incite inflammation.