This has resulted in the recently published review paper ‘The Benefits and Harms of Different Extents of Lymph Node Dissection During Radical Prostatectomy for Prostate Cancer: A Systematic Review’ by Fossati et al. in European Urology, on behalf of the guidelines panel. The review aims to systematically search for and summarize the comparative evidence of lymph node removal, and its extent, in addition to radical prostatectomy.
Open, laparoscopic or robot-assisted prostatectomy approaches were included. Besides cancer-specific outcomes, the surgical complications and functional outcomes were extracted from the total of 66 included articles. Due to strict selection, this included only three randomized controlled trials (RCT). None of these RCTs compared outcomes of no PLND versus (any) PLND, for oncological or non-oncological outcomes. The extent of lymph node dissection was categorized in five groups, but most studies did not even specify the template of the procedure. Comparisons between the different templates of lymph node dissection were also included in the review. Again, due to selection criteria, many papers comparing limited vs extended PLND based on the number of lymph nodes removed, were excluded. Most included (retrospective) studies had a high risk of bias, although most tried to adjust for stage and pathological factors. The above illustrates the scarcity of good quality data on this important clinical dilemma in prostate cancer management.
From a biological and clinical point of view, the most interesting question may be whether performing any PLND has clinical advantage over omitting a PLND. Comparing this intervention, most studies did not find any differences in biochemical recurrence, distant metastases, cancer-specific mortality or overall mortality outcomes. Some studies even found worse outcomes in patients who had undergone lymph node dissection. This feels counterintuitive, but might likely be due to unaccounted selection bias and baseline differences. Regarding non-oncological outcomes, the main side effect of PLND was the higher risk of lymphocele. Single studies did not find a difference in readmission rates or functional outcomes. Compared to a limited PLND, more extended lymph node removal showed conflicting results regarding oncological outcomes. There was a suggestion of less favourable intra-operative parameters (blood loss and operative time) and higher lymphocele rates, but no difference in functional outcomes.
In summary, the quality of evidence for oncological or peri-operative benefits of lymph node dissection and staging during prostatectomy is poor. No clear evidence was found that lymph node dissection during prostatectomy at all or that more extended dissection improves oncological outcomes. Besides, the procedure may come at the cost of less favorable intraoperative and perioperative outcomes. In the absence of level one evidence however, the clinical intuition prevails that for a subset of patients lymph node dissection may be beneficial or even curative.
Written by: Roderick CN van den Bergh and Peter-Paul M Willemse
Keywords: Prostate cancer, Surgery, Lymph node dissection, Staging, Oncological outcome
Read the original article in European Urology
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