San Antonio, Texas USA (UroToday.com) Chemotherapy in metastatic prostate cancer has assumed a new and important role in the space of hormone-sensitive metastatic prostate cancer. Data from the CHAARTED and STAMPEDE trials demonstrated a positive impact and improved survival for early chemotherapy in patients with hormone-sensitive prostate cancer.
Patients with oligometastatic disease (variably defined, but usually considered 1-3 metastatic sites) might be good candidates for systemic chemotherapy in an effort to eradicate disease from the few sites that currently harbor the tumor. However, the CHAARTED data clearly show that patients with higher disease burden appear have the most benefit, so timing of patient selection is key.
It is currently unclear if men who present with metastatic disease may have different disease than men who develop metastatic disease later. Indeed, other solid-organ malignancies such as colon cancer metastatic to liver can provide examples of how disease might sequentially progress. In this particular example, chemotherapy has been shown to play an important role in management.
There are 3 schools of thought on the biology of metastatic PC: 1) inherent CRPC exists by the time there are metastases; 2) micrometastases ALWAYS exist beyond the metastases we initially see; 3) micrometastases don’t yet exist but may come from sequential progression of the primary tumor. Gundem et al. published an interesting report in Nature in 2015 demonstrating a clonal lineage for prostate cancer cells in a metastatic patient, and this can act as a launching point to understanding metastatic progression in these patients.
Ultimately, we need to identify genomic signatures that can tell us who will have oligometastatic vs. systemic disease at presentation and follow-up. Further, what host-derived factors will provide the best environment for tumor treatment? As we study the use of chemotherapy in oligometastatic disease, we should try to develop a translational approach to defining genetic, clinical, and tumor burden characteristics that will lead to effective chemotherapeutic intervention in the right patient.
Presented By: Tanya B. Dorff, USC Keck School of Medicine
Written By: Shreyas Joshi, MD, Fox Chase Cancer Center
17th Annual Meeting of the Society of Urologic Oncology - November 30 -December 2, 2016 – San Antonio, Texas USA