Outcomes by tumor location in patients with metastatic colorectal cancer (mCRC) treated with regorafenib (REG): Final analysis from the prospective, observational CORRELATE study

539 Background: The anatomical location of the primary tumor has been associated with different prognosis and outcomes in mCRC. REG significantly improved overall survival (OS) versus placebo in patients with mCRC who progressed on standard therapies in phase 3 trials. We report the final results of outcomes in patients with mCRC with left-sided (L) or right-sided (R) primary tumors who were treated with REG in the real-world CORRELATE study. Methods: CORRELATE (NCT02042144) was a prospective, observational study designed to characterize the safety and effectiveness of REG in patients previously treated with approved therapies and for whom the decision to treat with REG was made by the treating physician according to the local health authority label. Patients with tumor location unknown or tumors in both regions were excluded (n = 62). OS was analyzed using the Kaplan–Meier method. Results: Overall, 975 patients were included in the analysis: L = 768 (79%) and R = 207 (21%). Most patients were ECOG PS 0–1 (L: 86%; R: 87%). Median time from initial diagnosis and from diagnosis of metastatic disease to REG treatment was slightly longer in L versus R tumors (34 vs 30 months and 27 vs 23 months, respectively). A higher proportion of patients with L versus R tumors, respectively, had prior radiotherapy (34% vs 15%) and a lower proportion had a partial colectomy (44% vs 75%). Both groups received a median of three prior regimens. REG treatment duration was similar in the two groups (median duration: L 2.6 months vs R 2.3 months), as was median progression-free survival (95% CI): 2.8 months (2.6, 2.9) for L tumors versus 2.7 months (2.5, 3.1) for R tumors. Median OS (95% CI) was 7.4 months (6.7, 8.0) for L tumors versus 8.2 months (6.6, 9.3) for R tumors; one-year OS rates were 32% versus 34%, respectively. Conclusions: Results from this observational study suggest that OS is similar in patients with L and R tumors treated with REG. Clinical trial information: NCT02042144.