Comparative Effectiveness of FOLFIRINOX Versus Gemcitabine and Nab-paclitaxel in Initially Unresectable Locally Advanced Pancreatic Cancer: A Population-based Study to Assess Subsequent Surgical Resection and Overall Survival.

AIMS: First-line FOLFIRINOX (FOLinic acid, Fluorouracil, IRINotecan, and OXaliplatin) and gemcitabine plus nab-paclitaxel (GnP) have been publicly funded for patients with unresectable locally advanced pancreatic cancer (uLAPC) in Ontario, Canada. We examined the overall survival and surgical resection rate after first-line FOLFIRINOX or GnP and determined the association between resection and overall survival in patients with uLAPC. MATERIALS AND METHODS: We conducted a retrospective population-based study including patients with uLAPC who received first-line treatment FOLFIRINOX or GnP from April 2015 to March 2019. The cohort was linked to administrative databases to ascertain demographic and clinical characteristics. Propensity score methods were used to balance differences between FOLFIRINOX and GnP. The Kaplan-Meier method was used to calculate overall survival. Cox regression was used to determine the association between receipt of treatment and overall survival, adjusting for time-dependent surgical resections. RESULTS: We identified 723 patients with uLAPC (mean age = 65.8, 43.5% female) who received FOLFIRINOX (55.2%) or GnP (44.8%). The median overall survival and 1-year overall survival probability were higher for FOLFIRINOX (13.7 months, 54.6%) than for GnP (8.7 months, 34.0%). Post-chemotherapy surgical resection occurred in 89 (12.3%) patients (FOLFIRINOX: 74 [18.5%] versus GnP: 15 [4.6%]), with no difference in survival since surgery between FOLFIRINOX and GnP (P = 0.29). After adjusting time-dependent post-treatment surgical resection, FOLFIRINOX (inverse probability treatment weighting hazard ratio 0.72, 95% confidence interval 0.61, 0.84) was independently associated with improved overall survival. CONCLUSIONS: In this real-world population-based study of patients with uLAPC, FOLFIRINOX was associated with improved survival and higher resection rates. FOLFIRINOX was associated with improved survival in patients with uLAPC after accounting for the effect of post-chemotherapy surgical resection, suggesting the benefit of FOLFIRINOX was not solely due to improving resectability.

Real-world Safety of Bevacizumab with First-line Combination Chemotherapy in Patients with Metastatic Colorectal Cancer: Population-based Retrospective Cohort Studies in Three Canadian Provinces.

AIMS: To examine the real-world safety of adding bevacizumab to first-line irinotecan-based chemotherapy for patients with metastatic colorectal cancer (mCRC). MATERIALS AND METHODS: Patients diagnosed with CRC in three Canadian provinces (Ontario, Saskatchewan and British Columbia) who received publicly funded bevacizumab and/or irinotecan from 2000 to 2016 were identified from cancer registries. Propensity score 1:1 matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to contemporaneous and historical controls, adjusting for baseline demographic and clinical characteristics. Safety end points evaluated during first-line treatment plus 30 days included mortality within 30 days and all-cause-, chemotherapy- and bevacizumab-related hospitalisations. Chemotherapy- and bevacizumab-related visits were defined as hospitalisations for specific conditions commonly associated with chemotherapy (e.g. infections) or bevacizumab (e.g. arteriovenous thromboembolism) using most responsible diagnosis codes. In PSM and IPTW-weighted cohorts, we assessed event frequencies using odds ratios from logistic regressions and event rate ratios using negative binomial regression models. The results from each province and comparison were pooled using random-effects meta-analysis. RESULTS: We identified 16 250 mCRC patients who received first-line irinotecan-based treatment. In PSM cohorts, bevacizumab was associated with fewer deaths within 30 days of treatment compared with contemporaneous (pooled odds ratio = 0.62; 95% confidence interval 0.50-0.75) and historical controls (pooled odds ratio = 0.73; 95% confidence interval 0.58-0.93). Hospitalisations were more frequent among patients treated with bevacizumab compared with historical controls but similar to contemporaneous controls. As patients receiving bevacizumab were exposed to a longer average treatment duration, across their full treatment duration, patients receiving bevacizumab had significantly lower rates of hospitalisations (contemporaneous pooled rate ratio = 0.56; 95% confidence interval 0.47-0.67; historical pooled rate ratio = 0.73; 95% confidence interval 0.56-0.95). Similar trends were observed for chemotherapy- and bevacizumab-related hospitalisations and in IPTW-weighted cohorts. DISCUSSION: We did not observe any increase in rates of hospitalisation or death within 30 days of treatment among mCRC patients treated with bevacizumab plus chemotherapy versus chemotherapy alone; these findings should be interpreted with caution due to the risk of residual confounding.