Publication-only abstracts (abstract number preceded by an "e"), published in conjunction with the 2019 ASCO Annual Meeting but not presented at the Meeting, can be found online only.
Carboplatin-based chemotherapy (C) versus immunotherapy (IO) in metastatic urothelial carcinoma (mUC).
Genitourinary (Nonprostate) Cancer
2019 ASCO Annual Meeting
J Clin Oncol 37, 2019 (suppl; abstr e16003)
Author(s): Emily Feld, Joanna Harton, Neal J. Meropol, Blythe J.S. Adamson, Ravi Bharat Parikh, Matt D. Galsky, Aaron B. Cohen, Vivek Narayan, John Paul Christodouleas, David J. Vaughn, Rebecca A. Hubbard, Ronac Mamtani; University of Pennsylvania, Philadelphia, PA; University of Pennsylvania Perelman School of Medicine, Department of Biostatistics and Epidemiology, Philadelphia, PA; Flatiron Health, New York, NY; Department of Medicine, Icahn School of Medicine at Mount Sinai, Tisch Cancer Institute, New York, NY; University of Pennsylvania, Department of Radiation Oncology, Philadelphia, PA; Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
Background: There are limited data comparing first-line (1L) C versus IO in cisplatin-ineligible mUC patients. The primary evidence guiding treatment decisions was a May 2018 Food and Drug Administration (FDA) safety alert based on early review of two ongoing phase III trials, reporting shorter survival in PD-L1 negative patients receiving IO relative to chemotherapy. Final results from these trials are unknown and may not be applicable to a real-world cohort. Methods: We conducted a retrospective cohort study of mUC patients receiving 1L C or IO from January 1, 2011 to May 18, 2018 using the Flatiron Health electronic health record-derived database. The primary outcome was overall survival (OS) from start of 1L treatment to date of death. We compared 12- and 36-month OS, and hazard ratios before and after 12 months. Propensity score-based inverse probability of treatment weighting (IPTW) was used to address confounding in Kaplan-Meier (KM) and Cox multivariable regression model estimates of comparative-effectiveness. Results: Of 2,243 patients, 562 received IO and 1,681 received C. Baseline characteristics were balanced between groups, with few exceptions (Table). In the first 12 months, IO was associated with an increased hazard of death compared to C (HR 1.38, 95% CI 1.16-1.66). Among patients who survived one year, survival was improved with IO compared to C (HR 0.50, 95% CI 0.27-0.92). Conclusions: In routine clinical practice, 1L IO was associated with inferior 12-month OS relative to C, but superior OS beyond 12 months. Clinicians and patients should carefully consider how to balance the early benefit of C against the late benefit of IO. Currently pending trial results will contribute additional evidence to inform treatment decision making.
(n = 562)
(n = 1681)
|Race white (%)||73||74|
|History of smoking (%)||74||72|
|PDL1 tested (%)||8||6|
|ECOG ≥2 (%)||22||12|
|Elixhauser comorbidity score, mean||2.28||1.07|
|OS, 12 months (%)||40.7||46.4|
|OS, 36 months (%)||29.1||13.7|
1. CALGB 90601 (Alliance): Randomized, double-blind, placebo-controlled phase III trial comparing gemcitabine and cisplatin with bevacizumab or placebo in patients with metastatic urothelial carcinoma.