Oligometastatic Prostate Adenocarcinoma. Clinical-Pathologic Study of a Histologically Under-Recognized Prostate Cancer

Current Treatment Paradigms and Clinical Outcomes in Oligometastatic Prostate Cancer Patients: A Targeted Literature Review

CONTEXT

Prostate cancer is the most common noncutaneous malignancy among men in the USA and Europe. There is no consensus definition of oligometastatic prostate cancer (omPC), which is often considered in two subgroups, synchronous (de novo) and metachronous (oligorecurrent), and may include patients with a low metastatic disease burden.

OBJECTIVE

To summarize the epidemiology, disease definitions, mortality/survival outcomes, and treatment characteristics in both clinical trial and real-world settings among patients with synchronous, metachronous, and mixed-subtype (ie, synchronous and metachronous or undefined type) omPC, as well as low burden disease states.

EVIDENCE ACQUISITION

We searched MEDLINE and Embase to identify publications reporting on epidemiology, disease definitions, clinical outcomes, and treatment characteristics of omPC. Gray literature sources (eg, ClinicalTrials.gov) were searched for ongoing trials.

EVIDENCE SYNTHESIS

We identified 105 publications. Disease definitions varied across publications and omPC subtypes on the number and location of lesions, type of imaging used, and type of oligometastatic disease. Most studies defined omPC as five or fewer metastatic lesions. Data on the epidemiology of omPC were limited. Mortality rates and overall survival tended to be worse among synchronous versus metachronous omPC cohorts. Progression-free survival was generally longer among synchronous than among metachronous omPC cohorts but was more similar at longer time points. A summary of ongoing clinical trials investigating a variety of local, metastasis-directed, and systemic therapies in men with omPC is also provided.

CONCLUSIONS

Definitions of oligometastatic disease depend on the imaging technique used. Epidemiologic data for omPC are scarce. Survival rates differ between synchronous and metachronous cohorts, and heterogeneous treatment patterns result in varied outcomes. Ongoing clinical trials using modern imaging techniques are awaited and needed.

PATIENT SUMMARY

Definitions of oligometastatic prostate cancer (omPC) vary depending on the imaging technique used. Different treatment patterns lead to different outcomes. Robust omPC epidemiologic data are lacking.

Focal therapy for primary tumor and metastases in de novo or recurrent oligometastatic prostate cancer: current standing and future perspectives

PURPOSE

Focal therapy (FT) is gaining increasing acceptance in the management of localized prostate cancer particularly due to its favorable safety. Preliminary evidence suggests advantageous utilization of local treatment in the field of oligometastatic prostate cancer (OMPC). Since data on the utilization of FT in OMPC are scarce, we sought to summarize available evidence.

METHODS

For this narrative comprehensive review, we employed PubMed®, Web of Science™, Embase®, Scopus®, and clinicaltrial.gov databases and Google web search engine to seek peer-reviewed articles, published abstracts from international congresses, and ongoing trials in the English language using the terms "prostate cancer", "oligometastatic", "hormone-sensitive", "focal therapy", "focal treatment", "cryotherapy", "ablation", "cancer" as well as "metastasis-directed therapy. We focused on relevant publications on FT utilized in OMPC targeting the primary or metastatic sites as well as completed and ongoing clinical trials.

RESULTS

Growing evidence points to distinct differences in the biologic behavior and molecular signaling processes of OMPC as compared to polymetastatic disease (PMPC). No established biomarkers are available to accurately identify OMPC yet, while several candidates are currently under investigation. The evolution of molecular imaging is set to aid in selecting patients benefitting most from local management. Differences between OMPC and PMPC should be considered when designing the optimal therapeutic strategy. While efficacy data for FT in comparison to standard care in OMPC are scarce, longer progression-free survival and time to castration resistance have been demonstrated for bone metastatic prostate cancer with the primary tumor treated by cryosurgery followed by androgen deprivation therapy (ADT) compared to ADT alone.

CONCLUSION

Ongoing research efforts are eagerly awaited to better characterize OMPC and establish customized strategies for patients with this condition.

Molecular Mechanisms Related with Oligometastatic Prostate Cancer-Is It Just a Matter of Numbers?

During the last decade, the body of knowledge regarding the oligometastatic state has increased exponentially. Several molecular frameworks have been established, aiding our understanding of metastatic spread caused by genetically unstable cells that adapt to a tissue environment which is distant from the primary tumor. In the current narrative review, we provide an overview of the current treatment landscape of oligometastatic cancer, focusing on the current biomarkers used in the identification of true oligometastatic disease and highlighting the impact of molecular imaging on stage shift in different scenarios. Finally, we address current and future directions regarding the use of genetic and epigenetic targeting treatments in oligometastatic prostate cancer.

Insights into Urological Cancer

The year the Covid-19 pandemic appeared has been quite prolific in urological cancer research, and the collection of articles, perspectives, and reviews on renal, prostate, and urinary tract tumors merged in this Urological Cancer 2020 issue is just a representative sample of this assertion [...].