The efficacy and safety of capecitabine plus bevacizumab combination as first-line treatment in elderly metastatic colorectal cancer patients

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

What is known and objectives

The optimal strategy for maintenance therapy in patients with metastatic colorectal cancer (mCRC) remains controversial. Considering that, beyond progression, co‐therapy with bevacizumab and cytotoxic chemotherapy showed less toxicity and a significant disease control rate. We aimed to investigate the differences in efficacy and safety between bevacizumab combined with capecitabine maintenance therapy and capecitabine monotherapy for RAS‐mutant mCRC （as defined by mutations in KRAS and NRAS exons 2–4）controlled by bevacizumab plus FOLFIRI chemotherapy for at least 12 weeks.

Methods

We retrospectively analysed patients with RAS‐mutant mCRC admitted to the Department of Oncology, Huizhou Municipal Central Hospital from December, 2015 to December, 2020. All patients were first treated with bevacizumab combined with FOLFIRI for at least 12 weeks of induction therapy. 154 patients whose disease was brought under control then continued maintenance therapy. 78 patients were in the observation group (bevacizumab plus capecitabine) and 76 patients were in the control group (capecitabine alone). The efficacy and adverse effects of maintenance treatment were compared between the two groups. The clinicopathological characteristics such as sex, age, performance status (PS) score, primary tumour site, degree of pathological differentiation, baseline carcinoembryonic antigen (CEA) level, microsatellite instability (MSI) status, number of metastatic tumour sites and efficacy of induction treatment were compared in terms of prognosis.

Results and discussion

The median progression‐free survival (mPFS)of patients was 9.0 months (95% CI 8.0–10.0) in the observation group and 7.2 months (95% CI 6.0–8.4) in the control group, with a statistically significant difference (p < 0.05). The baseline CEA level was an independent prognostic factor. Both groups tolerated the toxic side effects.

What is new and conclusion

Bevacizumab combined with capecitabine was well tolerated and contributed to a longer PFS time than capecitabine alone, and it is worthy of popularization in clinical practice.

Bevacizumab and erlotinib versus bevacizumab for colorectal cancer treatment: systematic review and meta-analysis

Background Improving the survival of patients diagnosed with metastatic colorectal cancer requires the use of chemotherapy to be managed with minimum adverse effects. Randomized control trials (RCTs) have shown promising results with a combination of bevacizumab and erlotinib to block two important tumor growth pathways, namely vascular endothelial growth factor and epidermal growth factor receptor. Aim of the Review We aimed to examine the efficacy and safety of the combination of bevacizumab and erlotinib with bevacizumab alone in the maintenance treatment of metastatic colorectal cancer, by examining PFS, OS, overall response rate (ORR), and toxicity. This study performed a systematic review meta-analysis using existing randomized clinical trial. Methods Randomized controlled trials were systematically reviewed from PubMed, Cochrane library, SCOPUS, CRD, and Google scholar databases. After evaluating the quality of studies through the Cochrane checklist, data of the relevant studies were extracted. This meta-analysis included outcomes of overall survival, progression-free survival of the disease through the hazard ratio, and the upper and lower confidence intervals for the third and fourth degree side effects of relative risk. To perform the meta-analysis for both types of survival, two fixed and random effect models were used. Results A total of three trials, providing data of 682 patients who received maintenance treatment, were included in this meta-analysis. Conclusion The combination of bevacizumab and erlotinib significantly increased the overall survival compared to using bevacizumab alone [HR = 0.78, 95% CI 0.66-0.93]. This combination, effectively increased progression-free survival [HR = 0.81, 95% CI 0.7-0.93] too. The side effects of diarrhea and grade III rash were more frequent in the group administered bevacizumab plus erlotinib. The combination of bevacizumab and erlotinib, in the maintenance treatment of metastatic colorectal cancer, significantly improved the overall survival and progression-free survival of patients, and the resulting side effects were easily treatable.

Association of baseline patient characteristics with adjuvant chemotherapy toxicities in stage III colorectal cancer patients

Toxicities can affect cancer patients' quality of life resulting in poor adherence to adjuvant chemotherapy (AC). While previous studies have explored the prevalence of toxicities following AC, few have examined the associations of baseline characteristics, such as age, sex, and performance status, with toxicity outcomes. In this study, we reviewed a cohort of 371 colorectal cancer patients treated with adjuvant monotherapy (capecitabine ) or combination therapy (FOLFOX or CAPOX) within 12 weeks of curative resection, and determined the associations between baseline characteristics and toxicity outcomes. Median age was 65 years, 52% were men, and 41% received monotherapy. A number of toxicities appeared to decrease with successive AC cycles. For monotherapy, univariate analyses found that age, sex, performance status, and pre-treatment anemia were associated with hematological toxicities whereas tumor location was associated with gastrointestinal (GI) toxicities (all P < 0.05). On multivariate analyses, hematological toxicities were predicted by advanced age (≥ 70) (OR 3.30; 95% CI 1.17-9.37; P = 0.025) and pre-treatment anemia (OR 23.18; 95% CI 6.36-84.48; P < 0.001), while GI toxicities were less likely to occur among tumors at or distal to the splenic flexure (OR 0.38; 95% CI 0.15-0.99; P = 0.047). For combination therapy, sex and pre-treatment anemia were associated with hematological toxicities (all P < 0.05), but only female sex was predictive on multivariate analyses (OR 5.13; 95% CI 2.08-12.68; P < 0.001). In conclusion, few baseline characteristics were associated with treatment toxicities. These findings may better inform discussions with patients and caregivers during AC decision-making and underscore to clinicians the need for close monitoring of patients during treatment.