EAU 2021: Treatment Options for Recurrent mHSPC: The Role of Imaging-Guided Treatments: Surgery

Long-term outcomes of patients treated with salvage lymph node dissection for nodal recurrence until recently were essentially unknown. As such, Bravi et al.¹ undertook a multi-institutional approach to assess these long-term outcomes, including 189 patients who experienced PSA rise and nodal-only recurrence after radical prostatectomy and underwent salvage lymph node dissection at 11 centers between 2002 and 2011. Recurrences were detected with either ¹¹C-choline or ⁶⁸Ga PSMA. The primary outcome was cancer-specific mortality, and the secondary outcomes were overall mortality, clinical recurrence, biochemical recurrence, and androgen deprivation therapy (ADT)-free survival after salvage lymph node dissection. There were 110 and 163 patients experienced clinical recurrence and biochemical recurrence, respectively, with clinical recurrence-free and biochemical recurrence-free survival at 10 years of 31% and 11%, respectively. After salvage lymph node dissection, a total of 145 patients received ADT, with a median time to ADT of 41 months:

Importantly, additional therapy was warranted in >60% of patients within 6 months of salvage lymph node dissection. At a median follow-up for survivors of 87 (IQR 51 to 104) months, 48 patients died, of which 45 died from prostate cancer. At multivariable analyses, patients who had PSA response after salvage lymph node dissection (HR 0.45; p = 0.001), and those receiving ADT within 6 months from salvage lymph node dissection (HR 0.51; p = 0.010) had lower risk of death from prostate cancer.

Dr. Maurer notes that the aim of salvage lymph node dissection should be to delay further (systemic palliative) therapy, and possibly cure a small portion of men. Selection of men for salvage lymph node dissection should include:

• Pelvic location
• Low number of metastases on imaging
• Low PSA prior to salvage lymph node dissection
• No ADT at the time of imaging/salvage lymph node dissection

Discussing unpublished data from Knipper et al., Dr. Maurer highlighted that between 2014 and 2020, there were 377 patients that had a PSMA PET based salvage lymph node dissection with 53.6% of men having a PSA <0.2 ng/mL after salvage surgery. On multivariable analysis, having one PSMA PET/CT lesion on imaging was significantly associated with biochemical recurrence-free survival after surgery:

Ultimately, Dr. Maurer emphasizes that what is need in the salvage lymph node dissection disease space is additional studies and registries. As follows is a summary of ongoing trials in the biochemical recurrent setting:

Dr. Maurer concluded his presentation with the following take home messages:

• Metastasis directed therapy is still outside the current guideline recommendations
• If considered, metastasis directed therapy should be based on novel molecular imaging (PSMA-PET)
• As follows is the proposed treatment landscape in BCR-setting:

Presented by: Tobias Maurer, MD, Martini-Klinik Prostate Cancer Center, University Hospital Hamburg-Eppendorf, Hamburg, Germany  

References:

1. Bravi CA, Fossai N, Gandaglia G, et al. Long-term Outcomes of Salvage Lymph node dissection for nodal recurrence of prostate cancer after radical prostatectomy: Not as Good as Previously Thought. Eur Urol2020 Nov;78(5):661-669.