MP16-12: Prognosis and Management of Non-Muscle Invasive Bladder Cancer with Pathologic Finding of Low Grade with Focal High Grade Features
Friday, May 3, 2024 1:00 PM to 3:00 PM · 2 hr. (US/Central)
221B
Abstract
Information
Full Abstract and Figures
Author Block
Rebecca A Campbell*, Andrew Wood, Akua Abrah, Marcello P Toscano, Samuel C Haywood, Mohamed Eltemamy, Christopher Weight, Steven C Campbell, Georges-Pascal Haber, Jesse McKenney, Jane Nyugen, Christopher Przybycin, Sean Williamson, Nima Almassi, Reza Alaghehbandan, Cleveland, OH
Introduction
Low grade (LG) non-muscle invasive bladder cancer (NMIBC) with focal high grade (HG) component (will refer to as mixed grade NMIBC) is a pathologic finding defined as predominantly LG but with <5% HG present. Limited data exists on the clinical behavior and oncologic outcomes of these tumors. We sought to evaluate oncologic outcomes of mixed grade NMIBC compared to LG and HG NMIBC.
Methods
We conducted an archival search (2012-2023) and histologic review (by a genitourinary pathologist) of all patients with mixed grade NMIBC who underwent TURBT, yielding a final cohort of 77 patients. Further, we included 53 LG patients (including only those with low-risk as defined by AUA guidelines) and 130 HG patients (including intermediate and high-risk as defined by AUA guidelines) as control. Patients with very-high risk features including BCG unresponsiveness, variant histology, lymphovascular invasion, and prostatic urethral invasion were excluded. Outcome oncologic parameters were compared between the mixed grade and the control groups.
Results
Mean (±standard deviation) follow-up was 38.8 months (±33.9). Prior history of bladder cancer was present in 7/53 (13.2%) of LG patients, 20/77 (26.0%) of mixed grade patients, and 46/130 (35.4%) of HG patients. Intravesical therapy was administered in 5/53 (9.4%) of LG patients, 31/77 (40.3%) of mixed grade patients and 86/130 (66.2%) of HG patients, with BCG being the most common across all cohorts. Any recurrence occurred in 11/53 (20.8%) LG, 30/77 (39.0%) mixed, and 37/130 (28.5%) HG patients (p=0.086). HG recurrence occurred in 0 LG, 16/77 (20.8%) mixed, and 37/130 (28.5%) HG (p<0.0001). Mixed and HG patients had significantly lower HG-recurrence free survival (HG-RFS) compared to LG patients (p<0.01 for both), but there was no statistically significant difference between mixed and high-grade patients for HG-RFS (p=0.1) (Figure).
Conclusions
HG-RFS was similar between the mixed and HG NMIBC, suggesting that mixed grade patients should be treated similarly to HG patients when making management decisions about intravesical therapy.
Source Of Funding
None
Author Block
Rebecca A Campbell*, Andrew Wood, Akua Abrah, Marcello P Toscano, Samuel C Haywood, Mohamed Eltemamy, Christopher Weight, Steven C Campbell, Georges-Pascal Haber, Jesse McKenney, Jane Nyugen, Christopher Przybycin, Sean Williamson, Nima Almassi, Reza Alaghehbandan, Cleveland, OH
Introduction
Low grade (LG) non-muscle invasive bladder cancer (NMIBC) with focal high grade (HG) component (will refer to as mixed grade NMIBC) is a pathologic finding defined as predominantly LG but with <5% HG present. Limited data exists on the clinical behavior and oncologic outcomes of these tumors. We sought to evaluate oncologic outcomes of mixed grade NMIBC compared to LG and HG NMIBC.
Methods
We conducted an archival search (2012-2023) and histologic review (by a genitourinary pathologist) of all patients with mixed grade NMIBC who underwent TURBT, yielding a final cohort of 77 patients. Further, we included 53 LG patients (including only those with low-risk as defined by AUA guidelines) and 130 HG patients (including intermediate and high-risk as defined by AUA guidelines) as control. Patients with very-high risk features including BCG unresponsiveness, variant histology, lymphovascular invasion, and prostatic urethral invasion were excluded. Outcome oncologic parameters were compared between the mixed grade and the control groups.
Results
Mean (±standard deviation) follow-up was 38.8 months (±33.9). Prior history of bladder cancer was present in 7/53 (13.2%) of LG patients, 20/77 (26.0%) of mixed grade patients, and 46/130 (35.4%) of HG patients. Intravesical therapy was administered in 5/53 (9.4%) of LG patients, 31/77 (40.3%) of mixed grade patients and 86/130 (66.2%) of HG patients, with BCG being the most common across all cohorts. Any recurrence occurred in 11/53 (20.8%) LG, 30/77 (39.0%) mixed, and 37/130 (28.5%) HG patients (p=0.086). HG recurrence occurred in 0 LG, 16/77 (20.8%) mixed, and 37/130 (28.5%) HG (p<0.0001). Mixed and HG patients had significantly lower HG-recurrence free survival (HG-RFS) compared to LG patients (p<0.01 for both), but there was no statistically significant difference between mixed and high-grade patients for HG-RFS (p=0.1) (Figure).
Conclusions
HG-RFS was similar between the mixed and HG NMIBC, suggesting that mixed grade patients should be treated similarly to HG patients when making management decisions about intravesical therapy.
Source Of Funding
None