Capecitabine plus bevacizumab versus capecitabine in maintenance treatment for untreated characterised KRAS exon 2 wild-type metastatic colorectal cancer: a retrospective analysis in Chinese postmenopausal women

Abstract

BackgroundCapecitabine plus bevacizumab (CAP-B) maintenance treatment after 6 cycles of capecitabine, oxaliplatin, and bevacizumab (CAPOXB) has demonstrated clinical activity and failure to compromise quality of life in patients with metastatic colorectal cancer (MCC) in a previous phase 3 CAIRO3 study. The objective of this study is to evaluate the efficacy and safety of CAP-B versus CAP in maintenance treatment after 6-cycle CAPOXB induction therapy in Chinese postmenopausal women with untreated characterised KRAS exon 2 wild-type MCC.MethodsDuring 2012–2016, prospectively maintained databases were reviewed to evaluate cohorts with untreated characterised KRAS exon 2 wild-type MCC and stable disease or better after 6-cycle CAPOXB induction treatment. After induction treatment, all patients received either CAP-B or capecitabine (CAP) as maintenance treatment. Median progression-free survival (mPFS) and median overall survival (mOS) were the primary endpoints. Safety was the secondary endpoint.ResultsA total of 263 women with untreated characterised KRAS exon 2 wild-type MCC and stable disease or better after 6-cycle CAPOXB induction treatment were included for the evaluation of efficacy and safety (CAP-B-treated cohort, n = 130 and CAP-treated cohort, n = 133). The mPFS was 11.5 months (95% confidence interval [CI], 5.6–17.4) and 9.2 months (95% CI, 3.6–14.8) for the CAP-B-treated and CAP-treated cohorts, respectively (HR 0.54, 95% CI 0.32~0.85; P = 0.013). The mOS was 16.2 months (95% CI, 11.4–18.7) and 12.4 months (95% CI, 10.6–15.5) for the CAP-B- and CAP-treated cohorts, respectively (HR 0.72, 95% CI 0.51~0.94; P = 0.022). The CAP-B-treated cohort experienced significantly more grade 3 or 4 diarrhoea (P < 0.001) than the CAP-treated cohort.ConclusionsCAP-B maintenance treatment after 6-cycle CAPOX-B in Chinese postmenopausal women with untreated KRAS exon 2 wild-type MCC is poorer tolerated but has a more modest, if any, benefit compared with that of CAP maintenance treatment.

Efficacy and safety analysis of bevacizumab combined with capecitabine in the maintenance treatment of RAS‐mutant metastatic colorectal cancer

“…However, in the previous phase 3 CAIRO3 trial, the analysis of untreated mCRC patients with the characterized KRAS exon 2 wt was ignored. The study by Su et al included 233 untreated female patients with characterized KRAS exon 2wt mCRC 12 . After six cycles of induction therapy (CAPOX‐B), all patients received capecitabine plus bevacizumab (CAP‐B) or capecitabine alone (CAP) as maintenance therapy.…”

“…The study by Su et al included 233 untreated female patients with characterized KRAS exon 2wt mCRC. 12 After six cycles of induction therapy (CAPOX‐B), all patients received capecitabine plus bevacizumab (CAP‐B) or capecitabine alone (CAP) as maintenance therapy. The mPFS of the CAP‐B and the CAP treatment groups were 11.5 and 9.2 months (95% CI 5.6–17.4 vs. 95% CI 3.6–14.8; HR 0.54 [0.32~0.85], p = 0.013), respectively.…”

A novel cell-free single-molecule unique primer extension resequencing (cf-SUPER) technology for bladder cancer non-invasive detection in urine

“…For non-urological tumors, some somatic cell mutations and methylation changes were detected in the patient's ucfDNA. For example, A research which detects KRAS mutations in urine/serum/plasma in patients with colorectal cancer found that urine cfDNA provides more abundant mutation information and detects up to 95% of the KRAS mutation ratio than the rate of KRAS mutation detected in the blood cfDNA (35-40%) (22).…”