Presentation Authors: Marcus Daniels*, Trinity Bivalacqua, Andres Matoso, Max Kates, Baltimore, MD
Introduction: In 2017, the AJCC updated guidelines for the staging of bladder cancer. The new guidelines subdivided prognostic stage groups 3 and 4 into four groups based on regional lymph node (LN) and metastasis location. In the 7th edition, T3A-T4A N0 M0 were group 3 while group 4 included T4B, N1-3, and M1 patients. In the 8th Edition guidelines: group 3A includes T3A-T4A and N1 patients, group 3B includes N2-3 patients, group 4A includes T4B and M1A patients, and group 4B includes M1B patients. We sought to justify these changes in our institutional cohort.
Methods: We retrospectively identified radical cystectomy patients with T3A-T4B N0 M0 disease and patients with N1-3 disease at our institution (2000-2016). Eight or more LN removed was considered appropriate to determine LN status. Patients were stratified according to AJCC 7th and 8th Edition staging. Baseline differences in demographics were compared and Kaplan-Meier curves were constructed to assess recurrence free survival (RFS) and overall survival (OS) between groups. Recurrence was considered unknown if follow up time was less than 1 month.
Results: A total of 333 patients were included in the analysis. No T4B, N3, nor M1 patients were included due to limited sample size. Median LN removed was 18. Median follow-up time was 23.5 months. Demographics were similar between groups. Seventh edition Group 3 (n=153) and Group 4 (n=180) patients differed significantly in RFS (p= 0.032) and OS (p= 0.004). Eighth edition Group 3A (n=222) and Group 3B (n=111) patients differed in respect to RFS (p < 0.001) and OS (p < 0.001).
Conclusions: The 8th edition AJCC guidelines more accurately predict RFS and OS in muscle invasive and LN positive bladder cancer compared to the 7th edition guidelines. Specifically, characterizing N1-3 as Stage 3 and different from metastatic, Stage 4 disease, while differentiating solitary positive pelvic LN (Stage 3a) from multiple or distal positive LN (Stage 3b) more accurately prognosticates bladder cancer patients after cystectomy.