Imaging modalities in synchronous oligometastatic prostate cancer

Jurgen J Futterer,The Eau-Yau Prostate Cancer Working Party ,Igor Tsaur,Pieter J L De Visschere,Hendrik Borgmann,Prasanna Sooriakumaran,Alberto Briganti,Roderick Van Den Bergh,Guillaume Ploussard,Giorgio Gandaglia,Alexander Kretschmer,Derya Tilki,Cristian Surcel,Piet Ost,Massimo Valerio

doi:10.1007/s00345-018-2416-2

Abstract

PurposeAlong with a number of other malignancies, the term “oligometastatic” prostate cancer has recently emerged. It represents an attempt to define a subtype of cancer with a limited metastatic load that might perform more favorably than a distinctly disseminated disease, or even one that may be managed in a potentially curative way. Since there is currently a knowledge gap of what imaging modalities should be utilized to classify patients as having this type of tumor, we aimed to shed light on the role of conventional and marker-based imaging in the setting of synchronous oligometastatic prostate cancer as well as summarize the available evidence for its clinical application.MethodsA literature search on December 15th 2017 was conducted using the Pubmed database.ResultsFunctional imaging techniques like 68Ga PSMA. 68Ga PSMA PET-CT has currently been shown the best detection rates for the assessment of nodal, bone and visceral metastases, especially for smaller lesions at low PSA levels.ConclusionsFunctional imaging helps detect low-burden disease metastatic patients. However, these imaging modalities are not available in every center and thus clinicians may be prone to prescribe systemic treatment rather than referring patients for cytoreductive treatments. We hope that the ongoing prospective trials will help guide clinicians in making a more personalized management of synchronous metastatic patients.

Highlights

A total of 416,700 new cases of prostate cancer (PCa) were estimated to occur in Europe in 2012, while 92,200 males would succumb, making PCa besides non-melanoma skin cancers the most frequently diagnosed malignancy and at the same time the third leading cause of cancer death in men [1]
Preoperative staging with 68Ga prostate-specific membrane antigen (PSMA) PETCT appears to allow for more complete and accurate primary staging of PCa patients compared to standard routine imaging and may demonstrate a large number of otherwise unknown metastatic lesions, but its clinical role is yet to be definitively determined [40]
These patients would be treated with radical prostatectomy (± adjuvant radiotherapy) or primary radiotherapy + androgen deprivation therapy (ADT) based on the findings on conventional imaging according to the EAU guidelines [2] but using PSMA positron emission tomography (PET)-computed tomography (CT) we would diagnose occult oligometastatic PCa (OPCa) in some of them

Summary

Introduction

A total of 416,700 new cases of prostate cancer (PCa) were estimated to occur in Europe in 2012, while 92,200 males would succumb, making PCa besides non-melanoma skin cancers the most frequently diagnosed malignancy and at the same time the third leading cause of cancer death in men [1]. The practice of performing PSMA PET-CT as primary staging in patients with high-risk localized or locally advanced disease has already become a reality in some scenarios These patients would be treated with radical prostatectomy (± adjuvant radiotherapy) or primary radiotherapy + ADT based on the findings on conventional imaging (bone scan and CT) according to the EAU guidelines [2] but using PSMA PET-CT we would diagnose occult OPCa in some of them. On the other hand, using PSMA PET-CT in some OPCa patients (as defined by conventional imaging) would screen out those with falsepositive results, e.g., benign findings as bone hemangiomas, potentially shifting them to the cohort with clinically localized disease and enabling primary curative therapy Until these issues are not sufficiently clarified by the results of solid clinical trials, staging of primary Pca in routine clinical practice should still be performed with conventional imaging (bone scan and CT), we are aware of the limitations. In institutions where PSMA PET-CT is available, it could be used in cases of suspected OPCa to confirm the limited number of metastatic lesions but we are left to rely on empirical decisions and treatment strategy remains challenging

Conclusion

Findings

Compliance with ethical standards