Intravesical mitomycin-C-induced interstitial pneumonia.

An 84-year-old man with no evidence of pre-existing interstitial pneumonia developed fatal interstitial pneumonia and respiratory failure that could only be explained as an adverse effect of intravesical mitomycin C chemotherapy. He had undergone transurethral resection of bladder cancer 3 times, followed by intravesical mitomycin C chemotherapy 1 month later. He had received intravesical mitomycin C chemotherapy every week for 2 months, and he had complained of dyspnea on exertion 5 days before the last intravesical mitomycin C chemotherapy session. Interstitial infiltration was detected in both the upper and lower lobes of the left lung on the day of the last instillation of mitomycin C. Despite discontinuation of mitomycin C and administration of methylprednisolone, his condition deteriorated and he died. Diagnostic evaluation of other causes of pneumonia, including infection and collagen-vascular diseases, was negative. The autopsy demonstrated diffuse alveolar damage in the lung; there were no remarkable findings in other organs. To our knowledge, this is the first pathologically confirmed case of fatal interstitial pneumonia due to intravesical mitomycin C chemotherapy.