FLT1 and colorectal carcinoma: Fruquintinib, a specific VEGFR1 inhibitor, is now in phase 2 for metastatic CRC patients who failed second therapy (https://clinicaltrials.gov/ct2/show/NCT01975077?term=VEGFR1+colon&draw=2&rank=12; https://clinicaltrials.gov/ct2/show/NCT01762293?term=VEGFR1+colon&draw=2&rank=13; accessed on 15 April 2021).