Chen X, et al. - In this open-label, single-arm, phase II study, researchers tested apatinib (an oral vascular endothelial growth factor [VEGF] receptor-2 inhibitor) as a treatment option in patients with refractory metastatic colorectal cancer after failure of two or more lines of chemotherapy. Eligible patients were those with histological documentation of adenocarcinoma of the colon or rectum and who had received at least two prior regimens of standard therapies including fluoropyrimidine, oxaliplatin, and irinotecan. In the third-line or higher setting, apatinib in a daily dose of 500 mg, p.o., was administered to patients. Overall, 26 patients were included. The estimated median progression-free survival (PFS) of the whole group and median overall survival (OS) was 3.9 months and 7.9 months, respectively. Findings highlighted promising efficiency of apatinib monotherapy in the treatment of patients with refractory colorectal cancer, this therapeutic efficacy was particularly evident in patients with performance status (PS) 0–1 or no liver metastasis. In serial monitoring of tumor load, circulating tumor DNA (ctDNA) abundance could be a predictor.