68Ga-PSMA-11 PET-CT study in prostate cancer patients with biochemical recurrence and non-contributive 18F-Choline PET-CT: Impact on therapeutic decision-making and biomarker changes

Head-to-Head Comparison of [18F]F-choline and Imaging of Prostate-Specific Membrane Antigen, Using [18F]DCFPyL PET/CT, in Patients with Biochemical Recurrence of Prostate Cancer

PURPOSE

To analyse diagnostic and therapeutic impact of molecular imaging TNM (miTNM) stage obtained with [¹⁸F]DCFPyL versus [¹⁸F]F-choline in head-to-head comparison in biochemical recurrence (BCR) of prostate cancer (PCa).

MATERIAL AND METHODS

Patients with BCR of PCa after radical treatment with previous [¹⁸F]F-choline-PET/CT (negative or oligometastatic disease) were recruited to [¹⁸F]DCFPyL-PET/CT. Patients were classified according to: grade group, European Association of Urology classification, PSA, PSA doubling time (PSAdt) and PSA velocity (PSAvel). The overall detection rate (DR) and miTNM stage according to PROMISE criteria were assessed for both radiotracers and also correlated (Kappa). The influence of PSA and kinetics on both PET/CT (DR and miTNM) and predictive value of unfavourable kinetics on miTNM were determined. Cut-off PSA, PSAdt and PSAvel values able to predict PET/CT results were determined. Change in miTNM and treatment derived from [¹⁸F]DCFPyL information compared with [¹⁸F]F-choline were also evaluated.

RESULTS

We studied 138 patients. [¹⁸F]DCFPyL showed a higher DR than [¹⁸F]F-choline (64.5% versus 33.3%) with a fair agreement. [¹⁸F]DCFPyL and [¹⁸F]F-choline detected T in 33.3% versus 19.6%, N in 27.5% versus 13.8%, and M in 30.4% versus 8.7%. Both tracers' DR showed significant associations with PSA and PSAvel. Significant association was only found between miTNM and PSA on [¹⁸F]F-choline-PET/CT (p = 0.033). For [¹⁸F]F-choline and [¹⁸F]DCFPyL-PET/CT, a PSAdt cut-off of 4.09 and 5.59 months, respectively, were able to predict M stage. [¹⁸F]DCFPyL changed therapeutic management in 40/138 patients.

CONCLUSIONS

[¹⁸F]DCFPyL provides a higher DR and superior miTNM staging than [¹⁸F]F-choline in restaging BCR, especially with high PSA and unfavourable PSA kinetics, showing a fair agreement to [¹⁸F]F-choline.

Head-to-head comparison of 68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI in the detection of biochemical recurrence of prostate cancer: summary of head-to-head comparison studies

PURPOSE

Our meta-analysis aimed to evaluate the diagnostic performance of 68Ga-PSMA-11 PET/CT vs. 68Ga-PSMA-11 PET/MRI for biochemical recurrence of prostate cancer.

METHODS

We searched for relevant articles in PubMed and Embase until February 2022. Studies evaluating head-to-head comparison of 68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI in men with prostate cancer biochemical recurrence were included. The quality of each study was assessed using the Quality Assessment of Diagnostic Performance Studies-2 (QUADAS-2) tool.

RESULTS

A total of 5 studies with 219 patients were included in the analysis. The pooled overall detection rates of 68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI in detecting recurrent PCa after definitive treatment were 0.89 (95% CI: 0.65-1.00), 0.92 (95% CI: 0.77-1.00), while the detection rates were 0.20 (95% CI: 0.05-0.41) and 0.29 (95% CI: 0.10-0.53) in local recurrence, 0.51 (95% CI: 0.33-0.69) and 0.52 (95% CI: 0.44-0.61) in lymph node metastasis, 0.18 (95% CI: 0.07-0.33) and 0.20 (95% CI: 0.09-0.35) in bone metastasis. There was no significant difference between the two imaging modalities in the overall detection rate (P = 0.82). In addition, detection rates were also not significantly different in local recurrence, lymph node metastasis, or bone metastasis (P = 0.54, 1.00, 0.82).

CONCLUSIONS

68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI seem to have equivalent performance in detecting biochemical recurrence in prostate cancer. However, the results of the meta-analysis were drawn from studies with small samples. Further larger studies in this setting are warranted.

Management of Patients with Recurrent and Metachronous Oligometastatic Prostate Cancer in the Era of PSMA PET

Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) scans have higher sensitivity and specificity for detecting lymph nodes or metastatic disease relative to conventional imaging in prostate cancer staging. Since its FDA approval and incorporation into treatment guidelines, the use of PSMA PET has increased in patients undergoing initial staging, those with recurrence after initial definitive treatment, and patients with metastatic disease. Although the early detection of metastatic lesions is changing disease management, it is unclear whether this impact on management translates into clinical benefit. This review will summarize evidence pertaining to the change in patient management due to PSMA PET use and will discuss the implications of PSMA PET on treatment decisions in prostate cancer, particularly in the settings of biochemical recurrence and metachronous oligometastatic disease.

Prostate Cancer Biochemical Recurrence Resulted Negative on [68Ga]Ga-PSMA-11 but Positive on [18F]Fluoromethylcholine PET/CT

For prostate cancer (PCa) biochemical recurrence (BCR), the primarily suggested imaging technique by the European Association of Urology (EAU) guidelines is prostate-specific membrane antigen (PSMA) positron emission tomography/computer tomography (PET/CT). Indeed, the increased detection rate of PSMA PET/CT for early BCR has led to a fast and wide acceptance of this novel technology. However, PCa is a very heterogeneous disease, not always easily assessable with the highly specific PSMA PET with around 10% of cases occuring without PSMA expression. In this paper, we present the case of a patient with PCa BCR that resulted negative on [⁶⁸Ga]Ga-PSMA-11 PET/CT, but positive on [¹⁸F]Fluoromethylcholine (Choline) PET/CT.

The impact of PSMA PET on the treatment and outcomes of men with biochemical recurrence of prostate cancer: a systematic review and meta-analysis

BACKGROUND

Prostate-specific membrane antigen (PSMA) PET is highly sensitive in identifying disease recurrence in men with biochemical recurrence of prostate cancer (BCR) after primary therapy and is rapidly being adopted in clinical practice. The purpose of this systematic review and meta-analysis was to assess the documented impact of PSMA-PET on patient management and outcomes, including prostate-specific antigen (PSA) response, and intermediate and long-term outcome measures.

MATERIALS AND METHODS

MBASE, PubMed, Web of Science, Cochrane and OVID databases were searched for studies reporting on the impact of PSMA-PET on the management and outcomes of patients with BCR after definitive primary therapy. Outcome measures assessed included biochemical response to therapy after PET and BCR-free survival (BRFS). The proportions of patients in whom management changed, and the proportion of patients in whom each outcome measure was obtained were tabulated and pooled into meta-analysis using DerSimonian-Laird method.

RESULTS

A total of 34 studies with 3680 men reported change in management after PSMA-PET and 27 studies with 2639 men reported on at least one outcome measure and had follow-up data. PSMA-PET was positive in 2508/3680 (68.2%). The pooled proportion of change in management after PSMA-PET was 56.4% (95% CI, 48.0-63.9%). A decrease in serum PSA was documented in 72.4% of men (95% CI, 63.4-81.5%), and complete biochemical response in 23.3% (95% CI, 14.6-32.0%) at a median follow-up of 8.1 and 11 months, respectively. The pooled BRFS rate was 60.2% (95% CI, 49.1-71.4%) at a median follow-up of 20 months.

CONCLUSION

In conclusion, PSMA PET is positive in more than 2/3 of men with BCR and impacts patient management in more than half of the men. BRFS after PET-directed management is 60% at a median of 20 months after salvage therapy, and complete biochemical response may be achieved in up to a quarter of men.

68Ga-Prostate-specific membrane antigen (psma) positron emission tomography (pet) in prostate cancer: a systematic review and meta-analysis

Introduction:

Prostate cancer (PC) is the second most commonly diagnosed cancer in males. ⁶⁸Ga-PSMA PET/CT, a non-invasive diagnostic tool to evaluate PC with prostate-specific membrane antigen (PSMA) expression, has emerged as a more accurate alternative to assess disease staging. We aimed to identify predictors of positive ⁶⁸Ga-PSMA PET and the accuracy of this technique.

Materials and methods:

Diagnostic accuracy cross-sectional study with prospective and retrospective approaches. We performed a comprehensive literature search on PubMed, Cochrane Library, and Embase database in search of studies including PC patients submitted to radical prostatectomy or radiotherapy with curative intent and presented biochemical recurrence following ASTRO 1996 criteria. A total of 35 studies involving 3910 patients submitted to 68-Ga-PSMA PET were included and independently assessed by two authors: 8 studies on diagnosis, four on staging, and 23 studies on restaging purposes. The significance level was α=0.05.

Results:

pooled sensitivity and specificity were 0.90 (0.86-0.93) and 0.90 (0.82-0.96), respectively, for diagnostic purposes; as for staging, pooled sensitivity and specificity were 0.93 (0.86-0.98) and 0.96 (0.92-0.99), respectively. In the restaging scenario, pooled sensitivity and specificity were 0.76 (0.74-0.78) and 0.45 (0.27-0.58), respectively, considering the identification of prostate cancer in each described situation. We also obtained specificity and sensitivity results for PSA subdivisions.

Conclusion:

⁶⁸Ga-PSMA PET provides higher sensitivity and specificity than traditional imaging for prostate cancer.

Survey by the French Medicine Agency (ANSM) of the imaging protocol, detection rate, and safety of 68Ga-PSMA-11 PET/CT in the biochemical recurrence of prostate cancer in case of negative or equivocal 18F-fluorocholine PET/CT: 1084 examinations

Introduction

Despite growing evidence of a superior diagnostic performance of ⁶⁸Ga-PSMA-11 over ¹⁸F-fluorocholine (FCH) PET/CT, the number of PET/CT centres able to label on site with gallium-68 is still currently limited. Therefore, patients with biochemical recurrence (BCR) of prostate cancer frequently undergo FCH as the 1st-line PET/CT. Actually, the positivity rate (PR) of a second-line PSMA-11 PET/CT in case of negative FCH PET/CT has only been reported in few short series, in a total of 185 patients. Our aims were to check (1) whether the excellent PR reported with PSMA-11 is also obtained in BCR patients whose recent FCH PET/CT was negative or equivocal; (2) in which biochemical and clinical context a high PSMA-11 PET/CT PR may be expected in those patients, in particular revealing an oligometastatic pattern; (3) whether among the various imaging protocols for PSMA-11 PET/CT used in France, one yields a significantly highest PR; (4) the tolerance of PSMA-11.

Patients and methods

Six centres performed ⁶⁸Ga-PSMA-11 PET/CTs during the first 3 years of its use in France. Prior to each PET/CT, the patient’s data were submitted prospectively for authorisation to ANSM, the French Medicine Agency. The on-site readings of 1084 PSMA-11 PET/CTs in BCR patients whose recent FCH PET/CTs resulted negative or equivocal were pooled and analysed.

Results

(1) The overall PR was 68%; for a median serum PSA level (sPSA) of 1.7 ng/mL, an oligometastatic pattern (1–3 foci) was observed in 31% of the cases overall; (2) PR was significantly related to sPSA (from 41% if < 0.2 ng/mL to 81% if ≥ 2 ng/mL), to patients’ age, to initial therapy (64% if prostatectomy vs. 85% without prostatectomy due to frequent foci in the prostate fossa), to whether FCH PET/CT was negative or equivocal (PR = 62% vs. 82%), and to previous BCR (PR = 63% for 1st BCR vs. 72% in case of previous BCR); (3) no significant difference in PR was found according to the imaging protocol: injected activity, administration of a contrast agent and/or of furosemide, dose length product, one single or multiple time points of image acquisition; (4) no adverse event was reported after PSMA-11 injection, even associated with a contrast agent and/or furosemide.

Conclusion

Compared with the performance of PSMA-11 PET/CT in BCR reported independently of FCH PET/CT in 6 large published series (n > 200), the selection based on FCH PET/CT resulted in no difference of PSMA-11 PR for sPSA < 1 ng/mL but in a slightly lower PR for sPSA ≥ 1 ng/mL, probably because FCH performs rather well at this sPSA and very occult BCR was over-represented in our cohort. An oligometastatic pattern paving the way to targeted therapy was observed in one fourth to one third of the cases, according to the clinico-biochemical context of the BCR. Systematic dual or triple acquisition time points or administration of a contrast agent and/or furosemide did not bring a significant added value for PSMA-11 PET/CT positivity and should be decided on individual bases.

Impact of 68 Gallium prostate-specific membrane antigen tracers on the management of patients with prostate cancer who experience biochemical recurrence

OBJECTIVE

To investigate the impact of ⁶⁸ Gallium prostate-specific membrane antigen (⁶⁸ Ga-PSMA) tracers on the management of prostate cancer (PCa) patients with biochemical recurrence (BCR) by conducting a systematical review and meta-analysis.

MATERIALS AND METHODS

We performed a literature search of the PubMed, Embase and Web of Science databases up to 29 October 2019. We included studies that reported the proportion of patients whose management changed after ⁶⁸ Ga-PSMA tracers were used in patients with BCR. We used the Quality Assessment of Diagnostic Accuracy Studies-2 tool to evaluate the quality of the included studies. The proportion of patients with management changes were pooled using a random-effects model. Subgroup analyses and meta-regression analyses were performed to explore the source of heterogeneity. A Sankey diagram was used to show treatment change from before to after the use of ⁶⁸ Ga-PSMA tracers.

RESULTS

We included 20 eligible studies (2026 patients). The pooled proportion of patients with management change was 53% (95% confidence interval [CI] 46-60) in patients with BCR and 51% (95% CI, 34-67) in patients with early BCR (prostate-specific antigen [PSA] <0.5 ng/mL). The pooled positron-emission tomography-positive rate in patients with BCR was 68% (95% CI 59-78). Fourteen studies reported management change, with most changes being intermodal in nature (42%, vs 17% intramodal change).

CONCLUSIONS

The use of ⁶⁸ Ga-PSMA tracers altered the management of more than half of PCa patients with BCR, including those with early BCR. ⁶⁸ Ga-PSMA tracers might be used to guide individualized treatment in patients with BCR, particularly those with early BCR.

(Radio)Theranostic Patient Management in Oncology Exemplified by Neuroendocrine Neoplasms, Prostate Cancer, and Breast Cancer

The role of nuclear medicine in the management of oncological patients has expanded during last two decades. The number of radiopharmaceuticals contributing to the realization of theranostics/radiotheranostics in the context of personalized medicine is increasing. This review is focused on the examples of targeted (radio)pharmaceuticals for the imaging and therapy of neuroendocrine neoplasms (NENs), prostate cancer, and breast cancer. These examples strongly demonstrate the tendency of nuclear medicine development towards personalized medicine.

[Prostate-specific membrane antigen (PSMA)-based diagnostics and treatment of prostate cancer]

BACKGROUND

Since their clinical introduction in 2011, PSMA-PET/CT (PSMA: prostate-specific membrane antigen) as well as PSMA therapy of prostate cancer (PC) have spread rapidly worldwide.

OBJECTIVES

To summarize the current knowledge about both PSMA-PET/CT and PSMA therapy of PC.

METHODS

The knowledge derived from the literature as well as the authors' experiences were collected in this review.

RESULTS

PSMA-PET/CT demonstrates a very high sensitivity and specificity for the detection of recurrent PC as well as for the primary staging of intermediate- and high-risk PC. PSMA therapy shows promising results in third-line treatment for patients with castration-resistant, metastatic PC.

CONCLUSIONS

PSMA-PET/CT is meanwhile established as the gold standard for the detection of recurrent PC and is in the process of assuming the same role for primary staging of intermediate- to high-risk PC. PSMA therapy serves as a promising third-line therapy in an increasing number of centers.

Neuroendocrine differentiation in castration resistant prostate cancer. Nuclear medicine radiopharmaceuticals and imaging techniques: A narrative review

BACKGROUND

Androgen Deprivation Therapy (ADT) is the primary treatment for patients suffering from relapsing or advanced prostate cancer (PC). Hormone therapy generally guarantees adequate clinical control of the disease for some years, even in those patients affected by widespread skeletal and soft tissue metastases. Despite ADT, however, most patients treated with hormones eventually progress to castration-resistant prostate cancer (CRPC), for which there are no effective treatments. This clinical reality is an open challenge to the oncologist because of those neoplasms which elaborate neuroendocrine differentiation (NED).

METHODS

An online search of current and past literature on NED in CRPC was performed. Relevant articles dealing with the biological and pathological basis of NED, with nuclear medicine imaging in CRPC and somatostatin treatment in NED were analyzed.

EVIDENCE FROM THE LITERATURE

NED may arise in prostate cancer patients in the late stages of ADT. The onset of NED offers prognostic insight because it reflects a dramatic increase in the aggressive nature of the neoplasm. Several genetic, molecular, cytological and immunohistochemical markers are associated with this transformation. Among these, overexpression of somatostatin receptors, seen through Nuclear Medicine testing, is one of the most studied.

CONCLUSIONS

Preliminary studies show that the overexpression of somatostatin receptors related to NED in CRPC may easily be studied in vivo with PET/CT. This finding offers a potentially useful objective for targeted therapy in CRPC. If the overexpression of SSTRs is shown to afflict a significant segment of patients with CRPC, this will open further study of possible therapeutic options based on this marker.

177Lu-PSMA radioligand therapy of predominant lymph node metastatic prostate cancer

¹⁷⁷Lu-PSMA radioligand therapy (LuPRLT) is mainly used for patients with metastatic castration-resistant prostate cancer who are resistant to established drugs. This study describes LuPRLT, either LuPSMA I&T or LuPSMA RLT-617, for 45 patients with predominant lymph node metastatic prostate cancer (LNM PC). Thirty-five patients had LNM and ten patients had LNM and one or two bone metastases. Before LuPRLT, the patients had prostate specific antigen (PSA) of median 18 µg/l (interquartile range (IQR): 3.3–39). LuPRLT was given with a cumulative injected ¹⁷⁷Lu activity of median 14.5 GBq (IQR: 12.2–20.4). Maximum percentage decline of PSA was median 92% (IQR: 70–99). Thirty-five patients with only LNM had a better overall survival (OS) than ten patients with LNM and one or two bone metastases. Thirty-three docetaxel-naïve patients had a longer PSMA PET/CT progression-free survival than twelve patients who were resistant to docetaxel. Twenty-two patients who received LuPRLT with a cumulative injected ¹⁷⁷Lu activity ≥ 14.8 GBq had a better PSMA PET/CT progression-free survival than 23 patients who received LuPRLT with a lower cumulative injected ¹⁷⁷Lu activity. Seventeen patients with relapse after LuPRLT who received rechallenge LuPRLT or ActPRLT had a better OS than five patients who received other forms for relapse treatment. LuPRLT gave mild and transitory adverse effects. The findings of the present study suggest that LuPRLT of patients with LNM may be effective and safe. The promising results motivate randomized phase II trials to further quantify the impact of LuPRLT as treatment of patients with LNM.