Surgery, Combined Modality Offer Similar MIBC Outcomes
Meta-analysis reveals no significant difference in overall-, disease-specific, and progression-free survival between radical cystectomy and radiation-based, bladder preservation therapy.
Among muscle-invasive bladder cancer (MIBC) patients without distant metastases, no survival advantages emerged for radical cystectomy (RC) versus combined modality treatment (CMT) in a recent meta-analysis of studies published in the International Journal of Radiation Oncology Biology Physics.
Dharam Kaushik, MD, of the University of Texas Health Science Center in San Antonio, Texas, and colleagues reported results of a meta-analysis of 9554 patients from 8 prospective and retrospective studies published on or before March 2016.
The investigators found no significant differences in overall survival at 5 years (a 4% difference in hazard ratio favored CMT) or 10 years (a 2% difference favored RC). Likewise, disease-specific survival was similar between groups at 5 years (17% difference favored radiation) and 10 years (17% difference favored RC). Progression-free survival also appeared similar at 10 years (15% difference favored CMT).
Major complications occurred more frequently with RC, generally around the perioperative period. Rates of minor treatment-related complications were comparable between groups.
“According to the current available evidence, patients undergoing early RC likely share no survival or disease-related benefits compared with patients receiving radiation-based, bladder preservation therapy,” Dr Kaushik and the team concluded.
Since a third of CMT patients went on to have salvage RC, they pointed out that prompt salvage surgery after failed radiation therapy may be key to improved outcomes.
Although the review included 3 randomized controlled trials, none showed that overall survival was better with early surgery. Two of the trials offered preoperative radiation to RC patients, precluding analysis.
In addition, CMT was variably defined across studies included in the meta-analysis and did not reflect current standard of care including chemoradiation and maximal transurethral resection of bladder tumor.
Future, larger randomized trials are still needed to answer pivotal questions, according to the investigators. They are currently recruiting MIBC patients for a trial (NCT02716896) of CMT compared with RC in which patients with locally recurrent disease after bladder preservation therapy may select salvage RC. The findings may help identify the most appropriate patients for each treatment modality.
Vashistha V, Wang H, Mazzone A, et al. Radical Cystectomy Compared to Combined Modality Treatment for Muscle-Invasive Bladder Cancer: A Systematic Review and Meta-Analysis. Int J Radiation Oncol Biol Phys, vol.97,no.5;1002e1020. doi.org/10.1016/j.ijrobp.2016.11.056