Validation of Pathologic Substaging of “Deeply Invasive/Locally Aggressive” Urinary Bladder Cancers: A Data from the National Cancer Data Base (NCDB)
GP Paner, K Pollitt, A Stewart, B Bochner, J McKiernan, Members of AJCC GU Task Force, SS Chang, MB Amin. Loyola University Medical Center, Maywood, IL; American College of Surgeons, Chicago, IL; Cedars-Sinai Medical Center, Los Angeles, CA
Background: Urinary bladder cancer is the 4th leading cancer type and the 8th leading cause of cancer death in men in the United States (ACS, 2009). From the therapeutic standpoint, non-metastatic bladder cancers are grouped into “superficial” (pTa, pTis, pT1) and “deeply invasive/locally aggressive” (pT2, pT3, pT4) tumors, the latter group usually being candidates for more aggressive management. According to the 2002 AJCC staging, pT2 bladder cancers are further subdivided based on the depth of muscularis propria invasion into less than (pT2a) or more than half (pT2b) depth of invasion. Perivesical fat extension is further subdivided into microscopic (pT3a) or gross (pT3b) involvement. The purpose of this study is to validate the stratification capability and predictive value of pT2 and pT3 substaging in non-metastatic bladder cancers using materials from the NCDB.
Design: Cases are selected from NCDB bladder cancer data base entered 1998-1999 under primary site C67.0-C67.9 and limited to surgical 30-80 codes. Only pT2 and pT3 tumors are included with no documented nodal involvement and/or metastasis (pN0, pM0 or cM0).
Results: A total of 1,326 deeply invasive/locally aggressive bladder cancers fit our case criteria, including 323 (24%), 403 (30%), 376 (28%) and 224 (17%) pT2a, pT2b, pT3a and pT3b, respectively. In terms of survival, stratification is achieved across 4 substaging categories. The mean survival estimate for pT2a and pT2b is 48.7 (95% CI: 46.6 and 50.8) and 43.8 (95% CI: 41.6 and 45.9) months, respectively (p=0.021). At least 50% of both pT2 cohorts were alive at 60 months. The mean survival estimate for pT3a and pT3b is 35.1 (95% CI: 32.7 and37.4) and 31.5 (95% CI: 28.3 and 34.6) months, respectively (p=0.067).
Conclusions: This NCDB experience in bladder cancers validates the importance of pathologic substaging of muscle invasive bladder cancers. Trend and stratification is observed in the outcome of pT3a versus pT3b tumors, although this is not significant at the 0.05 cut-off. This NCDB data in bladder cancers has important implications in setting stage definitions to increase the prognostic accuracy of the future editions of the TNM staging.
Category: Genitourinary (including renal tumors)
Tuesday, March 23, 2010 1:00 PM
Poster Session IV # 92, Tuesday Afternoon