Long-term outcomes of definitive external-beam radiotherapy for non-metastatic castration-resistant prostate cancer

Carbon Ion Radiation Therapy for Nonmetastatic Castration-Resistant Prostate Cancer: A Retrospective Analysis

Purpose

Treatment outcomes of definitive photon radiation therapy for nonmetastatic castration-resistant prostate cancer (nmCRPC) are reportedly unsatisfactory. Carbon ion radiation therapy (CIRT) has shown favorable tumor control in various malignancies, including radioresistant tumors. Therefore, we retrospectively evaluated the clinical outcomes of CIRT for nmCRPC.

Methods and Materials

Patients with nmCRPC (N0M0) treated with CIRT at a total dose of 57.6 Gy (relative biologic effectiveness) in 16 fractions or 51.6 Gy (relative biologic effectiveness) in 12 fractions were included. The castration-resistant status received a diagnosis based on prostate-specific antigen kinetics showing a monotonic increase during primary androgen deprivation therapy or the need to change androgen deprivation therapy. Clinical factors associated with patient prognosis were explored. Twenty-three consecutive patients were identified from our database. The median follow-up period was 63.6 months (range, 14.1-120).

Results

Seven patients developed biochemical relapse, 6 had clinical relapse, and 4 died of the disease. The 5-year overall survival, local control rate, biochemical relapse-free survival, and clinical relapse-free survival were 87.5%, 95.7%, 70.3%, and 75.7%, respectively. One patient with diabetes mellitus requiring insulin injections and taking antiplatelet and anticoagulant drugs developed grade 3 hematuria and bladder tamponade after CIRT. None of the patients developed grade 4 or worse toxicity.

Conclusions

The present findings indicate the acceptable safety and favorable efficacy of CIRT, encouraging further research on CIRT for nmCRPC.

How PET-CT is Changing the Management of Non-metastatic Castration-resistant Prostate Cancer?: Comment la TEP-TDM Peut Modifier la Prise en Charge du Cancer de la Prostate Non Métastatique Résistant à la Castration ?

INTRODUCTION

The aim of this narrative review conducted by the Prostate Cancer Committee of the French Association of Urology (CC-AFU) was to provide an update on the current evidence for the impact of PET/CT in the management of men with non-metastatic castration-resistant prostate cancer (nmCRPC).

MATERIAL AND METHODS

This review is based on data available in the literature on PET/CT imaging for staging nmCRPC patients. A PubMed search and narrative review of the data were performed in March 2022. Only articles in French or English were considered.

RESULTS

Current guidelines recommend bone scan and CT scan as standard imaging modalities for staging and follow-up of patients with nmCRPC. Nearly one-third of asymptomatic patients with presumed nmCRPC ultimately have metastatic disease on conventional imaging. Increasing reports have shown that conventional imaging has limited accuracy in detecting metastatic disease in nmCRPC patients, leading to the development of next-generation imaging techniques. In a retrospective study, 18F-choline PET/CT detected distant metastases in 27/58 high-risk nmCRPC patients with prior negative conventional imaging. The implementation of radiolabeled ligands of the prostate-specific membrane antigen (PSMA) PET/CT in staging strategy has resulted in metastasis detection in 45% to 98% of patients with presumptive nmCRPC on conventional imaging. Such an early diagnosis of metastatic CRPC may allow patients to be referred for metastasis-directed therapies (i.e. stereotactic body radiotherapy), aimed at prolonging the efficacy of systemic therapies and improving clinical outcomes. However, current data are not strong enough to recommend this strategy, which must be properly evaluated in clinical trials. Indeed, the use of molecular imaging may lead to inappropriate undertreatment if the second-generation androgen receptor inhibitors (darolutamide, enzalutamide, apalutamide), which prolong life, are not used in the subgroup of patients with high PSA velocity (PSA doubling time <10 months).

CONCLUSION

Implementation of PSMA-PET/CT in the staging strategy would result in a migration of disease stage to extra-pelvic, M1 disease in at least half of presumed nmCRPC patients. The unprecedented accuracy of PSMA-PET/CT may pave the way for a more personalized treatment strategy. However, no data yet support this strategy for all nmCRPC patients as no oncologic benefit of early detection of M1 disease or MDT has been demonstrated. © 2022 Elsevier Masson SAS. All rights reserved.

Hong Kong Urological Association-Hong Kong Society of Uro-Oncology consensus statements on the management of advanced prostate cancer-2019 Updates

BACKGROUND

To update the Hong Kong Urological Association-Hong Kong Society of Uro-Oncology consensus statements on the management of advanced prostate cancer, the same panelists as in the previous consensus panel held a series of meetings to discuss updated clinical evidence and experiences.

METHODS

The previous consensus statements were retained, deleted, or revised, and new statements were added. At the final meeting, all statements were reviewed and amended as appropriate, followed by panel voting.

RESULTS

There were significant changes and additions to the previous consensus statements, primarily driven by the advances in androgen receptor signaling inhibitors, treatment sequencing in metastatic castration-resistant prostate cancer, and increasing recognition of oligometastatic prostate cancer since the introduction of prostate-specific membrane antigen positron emission tomography. In this update, a total of 59 consensus statements were accepted and established.

CONCLUSIONS

The consensus panel updated consensus statements on the management of advanced prostate cancer, aiming to allow physicians in the region to keep abreast of the recent evidence on optimal clinical practices.

Current and potential future role of PSMA-PET in patients with castration-resistant prostate cancer

PURPOSE

To review the current literature and discuss potential future roles of the novel positron emission tomography (PET) tracers targeting the prostate-specific membrane antigen (PSMA) in patients with castration-resistant prostate cancer (CRPC).

METHODS

A literature search on February 19th 2018 was conducted using the Medline database and www.clinicaltrials.gov . Additionally, illustrative cases of CRPC patients from our own institution who were restaged and treated based on PSMA-PET scan results are provided.

RESULTS

11 Studies met the inclusion criteria. PSMA-PET detected more metastatic lesions compared to conventional bone scan. Several patients were up-staged from non-metastatic CRPC (nmCRPC) to metastatic CRPC (mCRPC). Currently, no clear consensus exists regarding treatment response assessment in PSMA-PET scans for mCRPC patients undergoing treatment. Also, the role of PSMA-PET as a gatekeeper for systemic therapy or radioligands is currently undefined. PSMA-guided metastasis-directed radiotherapy may not only alleviate local symptoms but has the potential to defer systemic treatment in patients with oligoprogressive CRPC.

CONCLUSION

Compared to bone scan, PSMA-PET is more sensitive and specific to detect metastases but the therapeutic consequences of PSMA-PET results in the setting of CRPC remain unclear. Until future studies define the role of PSMA-PET in patients with CRPC, the current standard for imaging remains bone scan and computerized tomography.