Abstract Introduction Mitomycin, an alkylating chemotherapy agent historically used against many tumor types, is known to cause pulmonary toxicities when administered as part of systemic chemotherapy. We describe a case of pulmonary toxicity in a patient who received mitomycin via percutaneous nephrostomy tube as localized treatment for urothelial cancer. Case Description A 76 year-old man with a pertinent history of unilateral low-grade urothelial carcinoma, Parkinson’s disease, and type 2 diabetes mellitus presented with two months of progressive dyspnea on exertion and dry cough. He was found to be newly hypoxic and was admitted to the hospital. Three months prior to admission, he began a series of 5 treatments with mitomycin introduced via percutaneous nephrostomy tube. Treatment was completed approximately 6 weeks earlier. Baseline computed tomography (CT) scan of the chest was normal. Admission CT was notable for new bilateral patchy, nodular and ground-glass opacities in the lungs (Figure 1). Initial infectious workup was negative. He underwent bronchoscopy with bronchoalveolar lavage (BAL). Bronchoscopy was notable for lymphocytic predominance (58%); evaluation was negative for infectious etiology and cytology showed no evidence of malignancy. He was started on pulse-dose intravenous steroids then transitioned to oral steroids. Hypoxia rapidly improved but treatment was complicated by worsening of Parkinson’s tremor and hyperglycemia. Upon tapering steroids, his hypoxemia and dry cough quickly returned, leading to re-pulse dosing of intravenous steroids followed by a more gradual and prolonged oral steroid taper. He was able to slowly come down on supplemental oxygen needs, ultimately discharging on 3-4L nasal cannula at rest with plan for interval follow up and repeat imaging with pulmonology in the outpatient setting. Summary When administered as part of systemic chemotherapy regimens, mitomycin causes a variety of pulmonary toxicities including bronchospasm, interstitial pneumonitis, pulmonary fibrosis, diffuse alveolar damage, and pulmonary edema. Studies estimate clinically significant pulmonary toxicity to occur in 2-12% of cases. Because of these toxicities, mitomycin has been largely replaced by newer agents. More recently, directly instilled therapy with mitomycin has been used for treatment of urothelial cancer to minimize systemic symptoms while delivering high drug concentrations to the urothelium. Though rare, patients can still develop drug-related toxicities from this local instillation. Diagnosis relies on a thorough history, imaging, infectious workup, and consideration for bronchoscopy with BAL. Treatment should include immediate mitomycin discontinuation and systemic corticosteroid therapy. If overlooked as a potential offending agent based on route of administration, irreversible pulmonary damage can occur. This abstract is funded by: None
Wilson et al. (Fri,) studied this question.