Steroid-related emphysematous cystitis in an EGFR-mutant patient with lung adenocarcinoma while on gefitinib treatment

Advanced non-small cell lung cancer (NSCLC), the most lethal malignancy worldwide, obtains a small long-term benefit from chemotherapy. However, 16% of Caucasian patients presenting sensitizing mutations in the epidermal growth factor receptor have a high sensitivity to the tyrosine kinase inhibitor gefitinib. Gefitinib is a safe drug, with mild diarrhea, emesis, or skin rash the most common toxicities. However, rare adverse events such as pneumatosis intestinalis have been communicated. We first report a very rare case of emphysematous cystitis in a female patient with EGFR-mutant lung adenocarcinoma while on gefitinib treatment, taken advance to review risk factors for this infectious complication.