Retrospective Analysis of S-1 plus Bevacizumab as Maintenance Therapy after Induction of S-1 and Oxaliplatin (SOX) plus Bevacizumab as First-Line Chemotherapy in Patients with Metastatic Colorectal Cancer

摘要

Background:The SOFT study was a phase III trial designed to validate the non-inferiority of S-1 and oxaliplatin (SOX) plusbevacizumab to mFOLFOX6 plus bevacizumab in terms of PFS in patientswith metastatic colorectal cancer (mCRC) who had not previously receivedchemotherapy. In this study, we retrospectively reviewed cases in which S-1plus bevacizumab as maintenance therapy after induction of S-1 and Oxaliplatin(SOX) plus bevacizumab as first-line chemotherapy in patients with metastaticcolorectal cancer was applied in order to evaluate its efficacy and safety inclinical practice. Material and method: Among the 40 patients with mCRC at theFuchu Hospital who received SOX plus bevacizumabas a first line treatment between August 2013 and December 2018. The eligiblepatients had histologically confirmed mCRC. On day 1 of each 3-week period during the study,patients in the SOX plus bevacizumab received a 7.5 mg/kg intravenous infusionof bevacizumab, followed by an intravenous infusion of 130 mg/m2 oxaliplatin.S-1 (40 - 60 mg) wasadministered orally two times per day from after dinner on day 1 to after breakfast on day 15, followed by a 7-day rest. Results: The median PFS was 15.0 months and median OS was36.0 months. The response rate (RR: complete pus partial response) was 85.0%,and the disease control rate (DCR: RR plus stable disease) was 92.5%. The most common adverseevents with SOX plus bevacizumab were hypertension (50%), neurosensory toxicity(50%), anorexia (32.5%), fatigue (45%),pigmentation (39%), Neutrophil count decreased (30%), and platelet count decreased (40%). The mostcommon grade 3/4 adverse events wereneurosensory toxicity (5%) and fatigue (9%). Conclusion: This study revealed thatthe survival benefit of S-1 and oxaliplatin (SOX) plus bevacizumab in Japanesepatients with mCRC was like that observed in previous clinical trials.Therefore, S-1 and oxaliplatin (SOX) plus bevacizumab can be considered asroutine first-line treatment option for patients with mCRC.