(UroToday.com) The treatment for metastatic hormone-sensitive prostate cancer plenary session at the European Association of Urology 2021 annual meeting included a presentation by Dr. Alberto Briganti discussing surgery for local treatment to the primary +/- to the lymph nodes. Dr. Briganti notes that we must acknowledge that (i) there are no prospective randomized trials available assessing surgery in oligometastatic prostate cancer, (ii) surgery has been tested in retrospective/prospective registries only (with possible patient selection biases), (iii) there is no standardized post-radical prostatectomy treatments or use of metastasis directed therapies, and (iv) it is not yet clear if the results obtained by radiotherapy can also be applied to a radical prostatectomy series. As such, there is a low level of evidence for surgery in this disease space, but it is still practiced.
The EAU 2021 guidelines give a strong recommendation to offer ADT combined with prostate radiotherapy (using the doses from the STAMPEDE trial) to patients whose first presentation is M1 disease and who have low volume of disease by CHAARTED criteria. Dr. Briganti notes that based on these statements, there is indirect support for the fact that the outcome of radiotherapy cannot be extrapolated to surgery due to the lack of evidence.
Over the last decade, there have been several population-based studies assessing the outcomes of radical prostatectomy in the setting of oligometastatic disease. Generally, the 5-year survival data in these population-level studies ranges from 55% to 70%:
Without question, there are limitations to interpreting the data from these population studies, including:
- There is no information on the number and location of metastases
- There is no data on comorbidity profile, type of systemic therapies, as well as baseline hematological and/or biochemical blood values that represent established predictors of survival in metastatic prostate cancer
- There is no standardized use of peri-operative treatments
- There is no data on functional outcomes
- There are significant patient selection biases
Additionally, there are institutional series that have presented data in this disease space, generally with 2-year OS rates of 77%-89% and 5-year OS rates of 78%-80%:
Similar to the population-level studies, there are limitations with institutional series:
- These are retrospective series with inherent selection biases
- There is no standardized use of peri-operative treatments
- There are different definitions used for oligo-metastatic disease
- There is limited follow-up among these patients
In these patients with metastatic disease, should we be also targeting the lymph nodes? Data from the SEER database suggests that 199 of 330 patients (60.3%) treated with radical prostatectomy underwent lymph node dissection1. In this series, there was a significantly improved 5-year cancer-specific survival rate for those that received pelvic lymph node dissection in adjusted analyses (HR: 0.52, 95% CI 0.31-0.87; p=0.01):
In the institutional series, the most common complications from radical prostatectomy include lymphocele (8.5%-13%), transfusion (7.9%-14%), and DVT (7%-13%), whereas urinary continence rates did not vary substantially from non-metastatic radical prostatectomy series’. In Dr. Briganti’s opinion, the following patients are the optimal candidates for surgery:
- Low volume disease according to CHAARTED criteria/1-3 bone metastases
- Men with cN0 disease
- Gleason grade group 3-4 (versus 5)
- Patients with lower PSA (< 60 ng/mL according to a population-based series)
- Patients responding to neoadjuvant ADT
As follows is a list of the ongoing randomized controlled trials assessing surgery in the context of metastatic prostate cancer:
Dr. Briganti concluded his presentation by emphasizing that when considering surgery for patients with metastatic disease, this decision must be made in the context of good patient selection in experienced hands. However, cytoreductive radical prostatectomy should primarily be considered as an option for men with oligometastatic prostate cancer within the setting of a clinical trial.
Presented By: Alberto Briganti, MD, Ph.D., Urological Research Institute, IBCAS San Raffaele Scientific Institute, Milan, Italy
Written By: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2021 European Association of Urology, EAU 2021- Virtual Meeting, July 8-12, 2021.
References:
- Mazzonee, Priesser F, Nazzani S, et al. The effect of lymph node dissection in metastatic prostate cancer patients treated with radical prostatectomy: A contemporary analysis of survival and early post-operative outcomes. Eur Urol Oncol. 2019 Sep;2(5):541-548.