P-0187 - Incidence of Hepatic Resection among Colorectal Cancer Patients with Liver Metastases

Date 28 June 2014
Event World GI 2014
Session Poster Session
Topics Colon Cancer
Rectal Cancer
Surgery and/or Radiotherapy of Cancer
Presenter Keith Betts
Citation Annals of Oncology (2014) 25 (suppl_2): ii14-ii104. 10.1093/annonc/mdu165
Authors K. Betts1, S. Ogale2, M. Lu1, D. Zhuo1, H. Sharma1, R. Morlock3, N. Sommer2
  • 1Analysis Group, Inc., Boston/US
  • 2Genentech, Inc., South San Francisco/US
  • 3Independent, South San Francisco/US

Abstract

Introduction

Hepatic resection provides the best chance for long-term survival in colorectal cancer (CRC) patients with liver metastases. The objective of this study is to compare the real-world hepatic resection rates among CRC patients with liver metastases treated with first-line chemotherapy plus bevacizumab vs. chemotherapy alone.

Methods

Adults diagnosed with CRC and a subsequent secondary liver malignancy who received first-line chemotherapy were identified in the Truven Health MarketScan database (01/2008-06/2012). Patients were divided into chemotherapy plus bevacizumab and chemotherapy alone cohorts depending upon whether they received bevacizumab as part of their first-line treatment regimen. Patients were excluded if they had primary cancers other than CRC, previously had a liver resection, or were treated with monoclonal antibodies other than bevacizumab. Hepatic resections were identified using ICD-9-CM and CPT codes. Patients were followed from the first line therapy until hepatic resection or the end of follow-up. The time to hepatic resection was compared between the chemotherapy plus bevacizumab and chemotherapy alone cohorts using the Kaplan-Meier (KM) method and the log-rank test. A Cox Proportional Hazard (PH) model controlled for differences in patient demographics, comorbidities, tumor sites and prior cancer treatments.

Results

The study sample included 1,642 CRC patients with liver metastases. The mean age was 60.5 years and 60.1% of patients were males. During a median of 241 days of follow-up, a total of 14.2% (n = 233) patients had a hepatic resection. Compared with patients receiving chemotherapy alone (n = 942), a significantly greater proportion of patients receiving chemotherapy plus bevacizumab (n = 700) had a hepatic resection (log-rank p = 0.03). The KM rates of resection were 19.6% vs. 15.6% by 1-year and 24.1% vs. 20.1% by 2-years. The Cox PH model adjusting for potential confounders demonstrated that chemotherapy plus bevacizumab was associated with a higher incidence of hepatic resection than chemotherapy alone (hazard ratio = 1.33, 95% CI: 1.02, 1.73, p = 0.03).

Conclusion

This real-world analysis found that patients treated with chemotherapy plus bevacizumab had a significantly higher hepatic resection rate than patients treated with chemotherapy alone.