Authors:
 Samuel Bidot MD, Ashley Monsrud MD, Meredith Kline, Alexandra Speak, Mehmet Asim Bilen MD, Jeffrey Switchenko PhD MS, Yuzi Zhang, Amany Ghaly Gerges MD, Ghada Farhat PhD, Edward Alexander Dent MD ,Viraj A Master MD, Mazie Tinsley, Lara R Harik MD
 
 
 Affiliations:
 Emory University
 
 
 Abstract Body:
 "Prostatic carcinoma metastatic to the regional lymph nodes is staged as pN0, indicating the absence of metastatic disease, and pN1, indicating the presence of metastatic disease in regional lymph nodes. Patients with metastasis to non-regional lymph nodes are staged as pM1a. 
 
 We reviewed detailed clinical and histopathologic characteristics of 100 patients with prostatic carcinoma metastatic to the lymph nodes, focusing on nodal tumor burden. 
 
 Our patient cohort was a majority of white males (72/100, 72%) and also included 22 black patients (22/100, 22%). The majority of the cases had a Gleason score of 9 / Grade Group 5 (62/99, 63%). Thirty one patients had a Gleason score of 7, of which 22 patients had a minor tertiary Gleason pattern 5. Ninety seven patients (98%) had cribriform architecture. One patient had high grade neuroendocrine carcinoma. Most patients had extraprostatic extension or seminal vesicle invasion (pT3a and pT3b, 84/100, 84%), and a disease confined to the regional lymph nodes (pN1M0; 79/100, 79%). 
 
 On univariate analysis, parameters that were significantly associated with disease recurrence included: age> 65-year-old (p=0.005), ≥ 2 positive regional lymph nodes (p <0.001), and a maximum size of the tumor deposit ≥ 2mm (p=0.004). Disease recurrence was defined as biochemical, clinical or radiological recurrence or cancer-related death. Controlling for age, stage, size of the metastatic deposit and the presence of extranodal extension, patients with ≥ 2 positive regional lymph nodes were 3.2 times more likely (95%CI: 1.5–6.9; p=0.003) to have an unfavorable outcome. 
 
 In addition, disease-free survival of pN1M1a patients was not statistically different than patients with pN1M0 patients when controlling for the number of positive regional lymph nodes (p=0.27). 
 
 In light of our results, we propose a modification of the pathologic nodal staging for prostate carcinoma as follows: pN0-No evidence of metastatic disease, pN1-Presence of metastasis in only one regional lymph node (further sub-categorized into pN1a= metastatic deposit < 2 mm and pN1b= metastatic deposit ≥ 2 mm), pN2-Presence of metastasis in ≥ 2 regional lymph nodes, pN3- Presence of metastasis in abdominal non-regional lymph nodes. 
 
 We hope our proposed modification of the nodal staging of prostatic carcinoma will lead to further risk stratification of this high risk patient population, and tailored patient therapy, guided by the comparative risk of disease recurrence."
 
 
 Funding Acknowledgments:
 This research was supported in part by the Roswell Country Club Prostate Cancer Research Award, a philanthropic award provided by the Winship Cancer Institute of Emory University
 
 
 Corresponding Author Email:
 samuel.s.bidot@emory.edu
 
 
 Conflict of Interest:
 Nothing to Disclose

Proposal for Modification of the Nodal Staging of Metastatic Prostatic Carcinoma