Presentation Authors: Shaheen Alanee*, Mustafa Deebajah, Mohamed Alhamar, Absia Jabbar, Mireya Diaz-Insua, Sean Williamson, Daniel Schultz, James Peabody, Mani Menon, Nilesh Gupta, Detroit, MI
Introduction: To determine the association between the number of positive lymph nodes (LN), extranodal extension (ENE), size and Grade Group (GG) of metastatic focus (MET) in in the LN and risk of biochemical recurrence after prostatectomy in patients with prostate cancer (Pca).
Methods: We evaluated biochemical recurrence (BCR) in 280 node positive cases who underwent radical prostatectomy (RP) between 2006-2018 at our institution. Cases with prior treatment and known metastasis at the time of surgery were excluded. Parameters recorded included number & size of positive LN. Size & GG of largest MET & ENE were also noted.
Results: Average follow up period was 13.4 months. The Average number of LN retrieved was 14.7 with an average of 2 positive LN per case. ENE was identified in 99/244 (41%).Size of the largest positive LN was 10 mm or less in 71% of the cases and the size of the largest MET was < 2 mm (micrometastasis) in 107/261 cases (41%). A solitary LN positive was found in 166/280 (59%) of the cases, 95/280 (34%) had 2-4 LN positive, and 19/280 (7%) had 5 or more LN positive. GG of the MET was as follows GG1-2: 29/224(13%); GG3: 27/224 (12%); GG4-5: 168/224 (75%). Metastatic foci > 2 mm in size (macrometastasis), higher LN GG, higher number of positive LN (categorized as 1, 2-4 and > 5) & the presence of ENE were significantly associated with BCR. No significant differences were observed in unilateral vs bilateral involvement of the LN.
Conclusions: The current TNM classification for PCa includes only N0 and N1 categories. It does not stratify based on the characteristics of the LN metastasis. In our study, we demonstrate that these characteristics impact clinical outcome and should closely examined in patients with node positive disease identified after prostatectomy