[Analysis of metastatic colorectal cancer patients treated with regorafenib in real-world practice]

Objective: To evaluate the dose, efficacy and tolerability of regorafenib in a real-world clinical setting of metastatic colorectal cancer patients. Methods: The clinical data of patients with metastatic colorectal cancer who had received at least two previous treatment lines treated with regorafenib from May 2018 to December 2019 at National Cancer Center/Cancer Hospital was retrospectively analyzed. Patients'demographics, treatment, dosimetry, safety and survival data were collected. The primary endpoint was overall survival (OS). Results: A total of 114 patients were enrolled in this study, including male 83 and female 31, with a median age of 61.Of all patients, 83 were treated with regorafenib and 31 were given combination therapy with regorafenib. Starting dose was 80 mg in 57 (50.0%) patients, 120 mg in 24 (21.1%) patients, and 160 mg in 28 (24.6%) patients. Dose increases were observed in 30.9% (25/81) of patients receiving 80 mg and 120 mg as the initial dose. Forty-five (39.5%) and 36 (31.6%) patients took the last daily dose of 80 mg and 120 mg, respectively. Median follow-up time was 8.5 months.Objective response rate (ORR) and disease control rate(DCR) were 1.0% and 52.1%, respectively. The median progression free survivalrate (PFS) was 2.4 moths (95%CI: 0.80-10.57), median OS was 11.0 moths(95%CI: 9.03-not available). The difference of the PFS and OS in the different dose groups was not statistically significant. But patients who received 120 mg regorafenib showed much longer survival with a median OS of 16.7 month. The difference of survival between the regorafenib group and combination group was not statistically significant either. Twenty patients continued with regorafenib as treatment even after progression. These patients had longer survival compared with those (n=52) who stopped regorafenib with median OS of 16.7 month vs 9.1 month (χ(2)=2.305, P=0.116), respectively.There were 7.9%(9/114) of the patients who discontinued regorafenib therapy because of the adverse event, such as hand-foot skin reaction (HFSR), gastrointestinal bleeding, proteinuria and liver function injury. Conclusions: Patients with advanced colorectal cancer who failed to respond to standard therapy have a good survival benefit. The initial dose of 120 mg of regorafenib has a better risk/benefit ratio and is more suitable for patients with advanced colorectal cancer.