Fruquintinib-induced renal-limited thrombotic microangiopathy: a case report

Background Fruquintinib is a highly selective inhibitor of vascular endothelial growth factor receptor (VEGFR). Currently, there are no reported cases of fruquintinib causing kidney-restrictive thrombotic microangiopathy (TMA) in the available Chinese and foreign literature. Case presentation In this case report, we presented a 73-year-old patient receiving fruquintinib for metastatic colon cancer, manifesting abundant proteinuria, in which kidney-restrictive TMA was also diagnosed through renal biopsy. As far as we were concerned, this was the frst reported in terms of fruquintinib-induced kidney-restrictive TMA confrmed by renal biopsy. Conclusion This case indicates that fruquintinib may result in kidney-restrictive TMA, which is a rare but life-threatening complication of cancer treatment drug. Therefore, regular monitoring of proteinuria and blood pressure is imperative for all patients undergoing anti-VEGF drug therapy. And renal biopsy should be promptly conducted to facilitate early detection of thrombotic microangiopathy.