[804] Papillary Urothelial Neoplasm of Low Malignant Potential (PUNLMP): Outcome Analysis

TK Lee, H Miyamoto, JS Miller, DA Fajardo, GJ Netto. Johns Hopkins Hospital, Baltimore

Background: Few long-term single center studies have addressed outcome in patients (pts) with PUNLMP. The present study evaluates behavior of de novo primary urinary bladder primary PUNLMP lesions (Primary-PUNLMP) as well as PUNLMP diagnosed during surveillance for a higher grade urothelial neoplasm in upper or lower urinary tract (Surveillance-PUNLMP).
Design: Surgical pathology records were searched for all bladder PUNLMP diagnosed between 1998-2008. Electronic medical records were retrospectively reviewed.
Results: We identified a total of 63 PUNLMP of the bladder; 34 (54%) were categorized as Primary-PUNLMP and remaining 29 (46%) as Surveillance-PUNLMP. Primary-PUNLMP Group: Pts age ranged from 42-93 yrs (mean 63 yrs) with M:F ratio of 2:1. During F/U (range: 3-108 mos), 19/34 (56%) pts developed no recurrences. Among the remaining pts, 5/34 (15%) developed PUNLMP recurrences (1-2 episodes in 1-6 yrs) and 10 (29%) progressed to a higher grade lesions within 1-4 yrs. Grade progression was to non invasive low grade urothelial carcinoma (LG-TCC) in 26% and non invasive high grade urothelial carcinoma (HG-TCC) in 3%. None of our Primary-PUNLMP pts developed invasive carcinoma or died of dz. Tumor size did not correlate with likeliehood for recurrence (p:NS). Surveillance-PUNLMP Group : 19/29 (66%) of PUNLMP lesions in this group occurred during surveillance for higher grade lesion of UB. These included: 14 (74%) within 7 yrs of prior LG-TCC; 4 (21%) within 4 yrs of prior HG-TCC and 1 PUNLMP found in cystectomy for invasive carcinoma (InvTCC). The remaining 10 (34%) bladder PUNLMP developed during surveillance (1-13 yrs) after a prior upper tract urothelial neoplasm (3 InvTCC, 5 LG-TCC and 2 PUNLMP). Five pts in this group were lost to F/U (including 1 upper tract InvTCC) and 1 died of unrelated cause. Two pts died of urothelial carcinoma (both ureteral InvTCC; DOD: 7%), 11 are alive with disease (1 PUNLMP, 7 LG-TCC, 1 HG-TCC, and 2 InvTCC; AWD: 40%) and the remaining 10 are alive with no evidence of disease (NED: 34%).
Conclusions: Bladder PUNLMP can occur either as a de novo lesion or during surveillance for prior higher grade urothelial neoplasm of UB or UT. None of our Primary-PUNLMP pts developed invasive cracinoma or died of their disease despite a 54% recurrence and 29% grade progression rates. In contrast, Surveillance-PUNLMP were associated with worse outcome (45% grade/stage progression rate; 7% DOD and 40% AWD) most likely dictated by their initial higher grade/stage urothelial neoplasm.
Category: Genitourinary (including renal tumors)

Monday, March 9, 2009 2:30 PM

Platform Session: Section A, Monday Afternoon