Describing the Effectiveness of Palliative Gemcitabine in Patients With Advanced Pancreatic Cancer Treated at the Regional Cancer Centres of Ontario

Abstract

Background: Palliative gemcitabine has been shown to prevent the deterioration of well-being and to prolong survival of patients with pancreatic cancer in phase III randomized controlled trials (RCTs). It is unknown whether the efficacy reported in RCTs has translated into effectiveness in routine clinical practice. Objectives: 1) To describe the characteristics of patients with pancreatic cancer treated with palliative gemcitabine at the regional cancer centres (RCCs) of Ontario, 2) To describe: clinical benefit at two months, defined as stable or improved well-being; time to treatment discontinuation; and overall survival, 3) To identify factors associated with clinical benefit, and 4) To compare the effectiveness of gemcitabine with its reported efficacy in RCTs. Methods: This was a retrospective analysis of prospectively collected data. The study included patients with pancreatic cancer treated with palliative gemcitabine at the RCCs of Ontario between 2008 and 2011. Information about well-being was patient self-reported as captured by the Edmonton Symptom Assessment System (ESAS) at the RCCs. The proportions of patients that achieved clinical benefit were reported. Time to treatment discontinuation and overall survival were calculated using Kaplan –Meier survival analysis. Logistic regression was used to identify factors associated with clinical benefit. iii Results: The study population included 423 patients. Only 168 (39.1%) patients completed a pre-treatment ESAS. Patients completing a pre-treatment ESAS were not different than those that did not. Patients treated at RCCs were not different than those in RCTs. The median age of the study population was 65 years, 50% were male, 57% had stage IV disease and 94% had adenocarcinoma morphology. Thirty-seven percent of patients achieved clinical benefit at two months. Median time to treatment discontinuation and overall survival was 2 and 5.7 months, respectively. Stage and pre-treatment wellbeing were associated with clinical benefit at two months. Similar proportions of patients at RCCs and RCTs experienced clinical benefit. Time to treatment discontinuation and survival were similar as well. Conclusions: Efficacy of gemcitabine in RCTs has translated into effectiveness for patients treated at the RCCs of Ontario. It is unknown if this is true for patients not treated at the RCCs.