P2-059 - Treatment for regorafenib-resistant colorectal cancer patients

Abstract

Background: The activity and efficacy of regorafenib (RGR) in pretreated colorectal cancer (CRC) have been demonstrated through large clinical trials. However, the therapeutic strategy pertaining to patients with RGR-resistant CRC is yet to be established. In this single-center study, we retrospectively examined the clinical course of RGR-resistant CRC.Methods: Consecutive patients with unresectable or refractory metastatic CRC were recruited from the departments of medical oncology and surgery of the Ina Central Hospital. Therapeutic response, drug toxicity, and treatment duration were retrospectively reviewed. Results: Sixteen (8 men) patients were included. Median age of patients was 64 years (range, 42–86 years). Five patients had right colon cancer, 8 had left colon cancer, and 3 had rectal cancer. Median duration of treatment was 14 weeks (range, 1–38 weeks). Overall survival (OS) after initiation of RGR treatment was 34 weeks (range, 8–40 weeks); the duration of survival after the discontinuation of RGR was 22 weeks (range, 5–38 weeks). Twelve patients discontinued RGR because of disease progression. Best response was SD, which was observed in 9 patients (56%). OS was not influenced by the best response or duration or discontinuation of RGR. It was influenced only by consecutive chemotherapy, which was performed in 11 patients. OS in this group was 38 weeks, whereas that in the group who did not receive consecutive chemotherapy was 27 weeks. Duration of survival after the discontinuation of RGR was 27 weeks in the former group and 9 weeks in the latter. Consecutive chemotherapy included 6 cases with fluoropyrimidine and bevasizumab, 3 cases with TAS102 and 2 cases with irinotecan. No grade 3/4 adverse effects were associated with consecutive chemotherapy.Conclusion: Clinical response and duration of RGR treatment did not influence OS. Consecutive chemotherapy may improve survival of patients with RGR-resistant CRC with safety profile. Background: The activity and efficacy of regorafenib (RGR) in pretreated colorectal cancer (CRC) have been demonstrated through large clinical trials. However, the therapeutic strategy pertaining to patients with RGR-resistant CRC is yet to be established. In this single-center study, we retrospectively examined the clinical course of RGR-resistant CRC. Methods: Consecutive patients with unresectable or refractory metastatic CRC were recruited from the departments of medical oncology and surgery of the Ina Central Hospital. Therapeutic response, drug toxicity, and treatment duration were retrospectively reviewed. Results: Sixteen (8 men) patients were included. Median age of patients was 64 years (range, 42–86 years). Five patients had right colon cancer, 8 had left colon cancer, and 3 had rectal cancer. Median duration of treatment was 14 weeks (range, 1–38 weeks). Overall survival (OS) after initiation of RGR treatment was 34 weeks (range, 8–40 weeks); the duration of survival after the discontinuation of RGR was 22 weeks (range, 5–38 weeks). Twelve patients discontinued RGR because of disease progression. Best response was SD, which was observed in 9 patients (56%). OS was not influenced by the best response or duration or discontinuation of RGR. It was influenced only by consecutive chemotherapy, which was performed in 11 patients. OS in this group was 38 weeks, whereas that in the group who did not receive consecutive chemotherapy was 27 weeks. Duration of survival after the discontinuation of RGR was 27 weeks in the former group and 9 weeks in the latter. Consecutive chemotherapy included 6 cases with fluoropyrimidine and bevasizumab, 3 cases with TAS102 and 2 cases with irinotecan. No grade 3/4 adverse effects were associated with consecutive chemotherapy. Conclusion: Clinical response and duration of RGR treatment did not influence OS. Consecutive chemotherapy may improve survival of patients with RGR-resistant CRC with safety profile.