Table 1- The various definitions of high-risk prostate cancer:
Figure 1 – Use of radical treatment through the years:
The number of positive nodes removed has a clear effect on cumulative prostate cancer mortality, as can be seen in Figure 2. Multimodal treatment after surgery, including radiotherapy and ADT for node-positive PC, improves survival. 2
Figure 2 – Correlation between the number of nodes removed and mortality in prostate cancer patients:
Some additional points were next discussed by Wirth. These included the increased risk or 2nd cancer after radiotherapy. The hazard ratio was shown to be 2.08 (1.48-2.91, p<0.0001) for a second malignancy. 3 The addition of neoadjuvant hormonal therapy to RP, does not seem to improve survival.4 Another study compared the use of Flutamide (an anti-androgen) vs. control after RP in patients with stage T3-T4 NO in final pathology, demonstrating no difference in overall survival, but some difference in favor of the flutamide group in recurrence-free survival. 5 Postoperative radiotherapy for high-risk disease has been shown to improve biochemical progression-free survival (Figure 3). 6 No difference was seen in a trial assessing whether there is an advantage in biochemical free survival in patients with PT3N0 receiving adjuvant radiotherapy vs. early salvage radiotherapy (at a PSA<=0.5 ng/ml). 7
The last topic discussed was the oligometastatic PC. Data from a single center cancer registry demonstrates that RP does improve survival in these patients (Figure 3).8 Another trial comparing surveillance to metastases directed therapy (MDT) for oligometastatic PC recurrence, demonstrated an advantage for MDT over surveillance (Figure 4). [9] Lastly, ablative radiotherapy has been shown to improve castration resistant oligometastatic. 10
Figure 3: Postoperative radiotherapy for high-risk prostate cancer improves biochemical progression-free survival:
Figure 4: Comparison of surveillance of metastases directed therapy in oligometastatic PC:
Summarizing the talk, Wirth mentioned the good results that could be achieved with RP. Additionally, adjuvant or early radiotherapy improved disease control and offers 2nd chance of cure. Compared to radiotherapy, there is no increase in the risk of 2nd cancer risk. Importantly, RP manages to get superior local control.
References:
1. Choo et al. Ann Surg Oncol 2017
2. Abdollah et al. Eur Urol 2014
3. Nam et al. Lancet Oncology 2014
4. Shelley et al. Cancer Treat Rev 2009
5. Wirth et al. Eur Urol 2004
6. Bolla, van Poppel et al. Lancet 2012
7. Briganti, van Poppel, et al. Euro urol 2012
8. Gratze et al. Eur Urol 2014
9. Ost et al. JCO 2017
10. Lohaus, Wirth, Holscher et al.
Presented by: Manfred Wirth, MD, Dresden, Germany
Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at the 2018 FOIU 4th Friends of Israel Urological Symposium, July 3-5. 2018, Tel-Aviv, Israel