Aggressive Therapy for an Aggressive Disease: Treatment and Outcomes in Micropapillary Bladder Cancer

Selezionata da Pietro Cazzola

Bladder carcinomaDespite the fact that high-grade T1 bladder cancers are “noninvasive” lesions, they are aggressive and have a significant risk for progression to lethal disease. The standard of care for high-grade T1 tumors is intravesical bacillus Calmette-Guérin (BCG). For patients who do not respond or who progress with initial conservative therapy, radical cystectomy provides the best opportunity for long-term disease control. Given the aggressive nature of high-grade T1 bladder cancer, upfront radical cystectomy has been advocated, with the benefit of improved oncologic outcomes at the expense of undergoing a major surgery that incorporates some form of urinary diversion. The decision to proceed with radical cystectomy in the setting of high-grade T1 bladder cancer is often a difficult one for both patients and urologists.
Micropapillary bladder cancer is a rare histologic subtype of urothelial carcinoma that was first described in 1994. It has an extremely aggressive histology associated with a high risk for progression and metastatic disease. Given the aggressive nature of high-grade T1 bladder cancer with micropapillary features, it is currently debated whether patients with these lesions should be offered intravesical therapy. A recent study reported on a relatively large series of 72 patients with high-grade T1 micropapillary bladder cancer over a 22-year time period.1 Of these, 40 received intravesical BCG therapy, while 26 received upfront radical cystectomy; 75% percent of the patients treated with BCG ultimately suffered recurrence. More concerning, 45% progressed and 35% developed metastatic disease. The 5-year disease-specific survival for those who underwent immediate cystectomy was 100% compared with 60% for those treated with initial conservative therapy. Of note, 20% of patients treated with upfront cystectomy had lymph node–positive disease, again highlighting the aggressive nature of these lesions. The outcomes of patients who progressed after intravesical therapy were dismal (median survival was 35 months).
Clearly, micropapillary histology is a surrogate for aggressive bladder cancer. In appropriate surgical candidates, strong consideration should be given to upfront radical cystectomy in this patient population. Patients who are unwilling to undergo upfront cystectomy should be counseled regarding the potentially poorer oncologic outcomes associated with initial BCG therapy. Optimal diagnostic and treatment strategies need to be further elucidated in order to provide maximally aggressive surgical therapy to patients who are likely to benefit the most.

Written by Thomas J Guzzo MD, MPH