[A case of squamous cell carcinoma of the bladder in a patient with interstitial cystitis].

A 60-year-old woman with interstitial cystitis (IC), who had previously received hydrodistention surgery, intravesical instillation of resiniferatoxin and medication, was being followed. Although urinary cytology was regularly tested with no positive findings, computed tomography carried out for screening of recurrent colon cancer showed muscle-invasive squamous cell carcinoma (SCC) of the bladder (cT3bN0M0). Cystectomy was performed, but she died due to rapid disease progression at 3 months postoperatively. Chronic inflammation can be the cause of development of SCC. It is dubious whether the specific treatments for IC affected her disease. In cases of IC with persistent pyuria, the development of SCC should be kept in mind, and affirmative examination including cystoscopy should be done regularly for early detection of the disease.