Adjuvant chemotherapy improves survival in patients with locally advanced bladder cancer who did not receive the neoadjuvant chemotherapy that is currently advocated by some experts, according to a report published online Jan. 18 in Journal of Clinical Oncology.
Dr. Matthew D. Galsky
Two large randomized clinical trials and one meta-analysis demonstrated a survival advantage for patients who received neoadjuvant cisplatin-based chemotherapy, but three subsequent trials attempting to confirm those results were unable to do so: all three were terminated early because of poor accrual of study participants. At present, 1%-15% of eligible U.S. patients with muscle-invasive bladder cancer receive neoadjuvant chemotherapy. Clinicians favor adjuvant chemotherapy instead, “likely because of theoretic concerns regarding delaying potentially curative surgery and the ability to base treatment decisions on more precise pathologic, rather than clinical, staging,” said Dr. Matthew D. Galsky of Tisch Cancer Institute, Mount Sinai, N.Y., and his associates.
To further examine this issue, they analyzed information in the National Cancer Database, a registry that collects deidentified patient-level data from more than 1,500 U.S. hospitals with accredited cancer programs, which represents approximately 70% of all newly diagnosed cases across the country. For this observational study, the investigators focused on 5,653 patients who underwent radical cystectomy for urothelial bladder cancer during a 3-year period and who were found to have pathologic T3-4 and/or nodal involvement at surgery. A total of 1,293 patients (23%) then received multiagent chemotherapy while the remainder received no chemotherapy. All the patients were followed for a median of 7 years.
Compared with patients who did not receive adjuvant chemotherapy, those who did tended to be younger, have a higher income, have fewer comorbidities, and have positive surgical margins. The data were adjusted to account for these and other differences between the two study groups by using propensity-score matching.
Five-year overall survival was 37.0% with adjuvant chemotherapy and 29.1% without it, a significant difference favoring the treatment. In a further analysis, chemotherapy was associated with improved overall survival with an HR of 0.70. This survival benefit was strong across all subgroups of patients regardless of patient age, performance status, lymph node status, and a variety of other factors, and it remained robust in sensitivity analyses, Dr. Galsky and his associates said (J Clin Oncol. 2016 Jan. 18. doi:10.1200/JCO.2015.64.1076).
These findings “provide important information for facilitating treatment decisions.” Neoadjuvant chemotherapy followed by cystectomy remains the preferred approach, but for patients who don’t receive that, postcystectomy chemotherapy may still improve survival, they said.