A case of
cystitis occurring after administration of
nivolumab, an anti-programmed death-1 antibody, which was considered to be an immune-related adverse event, is reported. A 62-year-old man with pulmonary
squamous cell carcinoma (T4N0M1a Stage IV) was being treated with
nivolumab as fourth-line
chemotherapy. He was hospitalized for a
fever and
diarrhea after 3 courses. Fasting and
antibiotic medication reduced the
fever and alleviated the
diarrhea. He then developed
cystitis with no evidence of
infection. Cystoscopy showed diffused redness and erosion of the bladder mucosa; urine cytology was negative. Imaging examinations showed no abnormalities. Urinary tract
pain and
hematuria due to
nivolumab were diagnosed by exclusion following a bladder biopsy. Since symptomatic treatment was unsuccessful,
steroid pulse
therapy was given, which resolved the patient's signs and symptoms. The patient was then switched to maintenance
prednisolone and tapered gradually. The 4th course of
nivolumab was then resumed with concomitant administration of
steroid, and it was possible to continue administration of
nivolumab without progression of
cystitis.