Predictors of heterogeneity in the first-line treatment of patients with advanced/metastatic gastric cancer in the U.S.
- 249 Downloads
Patients with metastatic gastric cancer have a poor prognosis (5-year survival of less than 10%). This study was designed to describe the treatment patterns of patients with gastric cancer and to understand the factors associated with treatment choices to inform evidence-based care.
A retrospective observational study was conducted using two real-world databases to describe treatment trends and to quantify variability in treatment patterns of patients diagnosed with advanced/metastatic gastric cancer between 1/1/2007 and 9/30/2014 in the U.S. Heterogeneity was measured by the Herfindahl–Hirschman Index (HHI). Predictors (baseline clinical, treatment, and demographic variables) of treatment regimen choice were evaluated using logistic regression.
A total of 5772 patients with advanced/metastatic gastric cancer were included in this study [5044 from claims data and 728 from electronic medical records (EMR)]. Of the 5044 from claims data, 2457 had evidence of metastatic disease at diagnosis. Only the fluorouracil + oxaliplatin regimen exceeded 10% utilization in the first-line setting [claims metastatic (12.1%), claims advanced (8.2%), and EMR metastatic (16.6%) cohorts]. The HHI demonstrated extreme heterogeneity (0.14 for first-line therapy and 0.13 for second-line therapy). Patient age and geographic region of residence were significantly associated with treatment choice across all three cohorts in the first-line setting (p < 0.05).
Treatment of patients with gastric cancer was highly variable. Despite the availability of treatment guidelines, there is a lack of consistent treatment patterns. There is a need to improve evidence-based care for patients with gastric cancer.
KeywordsPopulation characteristics Stomach neoplasms Drug therapy Antineoplastic agents
This study was an unfunded research project conducted with the material support in the form of employee time and data resources by Eli Lilly and Company.
Compliance with ethical standards
Conflict of interest
LMH, YEZ, WS, and AML are employees of Eli Lilly and Company.
This study was deemed exempt from Institutional Review Board review in accordance with the US Code of Federal Regulations [45CFR46.101(b)] as these data do not contain any variables that could identify an individual subject either directly or indirectly.
- 3.Cancer stat facts: stomach cancer, SEER 18 2007–2013. https://seer.cancer.gov/statfacts/html/stomach.html.
- 4.NCCN Clinical practice guidelines in oncology, Gastric cancer version 4.2017 https://www.nccn.org/professionals/physician_gls/pdf/gastric.pdf.
- 5.Barzi A, Hess LM, Zhu YE, Liepa AM, Fang Y, Kuder C, Beyrer J, Chao J. Treatment and outcomes of patients with advanced gastric, esophageal, or gastroesophageal junction adenocarcinoma in the United States. Ann Oncol 2017;28(Suppl 3):35.Google Scholar
- 7.Hess LM, Michael D, Mytelka DS, Beyrer J, Liepa AM, Nicol S. Chemotherapy treatment patterns, costs, and outcomes of patients with gastric cancer in the United States: a retrospective analysis of electronic medical record (EMR) and administrative claims data. Gastric Cancer. 2016;19(2):607–15.CrossRefPubMedGoogle Scholar
- 8.Weinstock DS. Using the Herfindahl Index to measure concentration. Antitrust Bull. 1982;27:285.Google Scholar
- 12.Schelman WR, Paulson AP, Aguilar K, Clark J, Cui ZL, Liepa AM, Hess LM. Predictive factors associated with ramucirumab monotherapy or combination therapy among patients with gastric/gastroesophageal junction cancer in the community oncology setting. Ann Oncol 2017;28(Suppl 3):77.Google Scholar