OBJECTIVETo investigate the clinical and pathological characteristics of bevacizumab-induced renal impairment.

METHODThe clinical and pathological data of 4 patients with bevacizumab-induced renal impairment in Peking Union Medical College Hospital was retrospectively analyzed.

RESULTSThere were 2 men and 2 women aged (56.5±11.5) years. Before bevacizumab treatment, three non-small cell lung cancer patients (75%) had normal renal function and only one pancreatic cancer patient (25%) had mild renal impairment. After 2-14 cycles of bevacizumab treatment, the most common clinical manifestation of bevacizumab-induced renal injury was proteinuria (>3.5 g/d) (n=4, 100%). Other clinical symptoms included microscopic hematuria (n=2, 50%), malignant hypertension (n=1, 25%), elevated serum creatinine level as accompanied with acute renal failure (n=1, 25%), and anuria (n=1, 25%). Thrombotic microangiopathy was the main pathological type (n=2, 50%), whereas other pathological types included membranoproliferative glomerulonephritis (n=1, 25%) and benign arteriolar nephrosclerosis (n=1, 25%). After the detection of renal impairment, bevacizumab therapy was stopped in all 4 cases (100%). Hemodialysis was performed in the patient with acute renal failure. The prognosis was relatively good. The renal function and proteinuria was completely recovered in one patient (25%), whereas the other three patients (75%) presented with persistent alleviated proteinuria but normal renal function.

CONCLUSIONSBevacizumab may cause renal injury via complex mechanisms. Therefore, urine protein excretion and renal function should be closely monitored during bevacizumab treatment to identify any renal injury. The prognosis is relatively good after discontinuation of bevacizumab.