Significance of Inflammatory Pseudotumors in Patients with a History of Bladder Cancer

ObjectiveTo study the significance of inflammatory pseudotumor (IPT) in patients with a history of bladder cancer.MethodsWe surveyed our hospital database for patients who developed IPT during follow-up of bladder cancer. The original histologic blocks were reviewed and immunostained for vimentin, anaplastic large cell lymphoma (ALK), and pancytokeratin.ResultsBetween the years 1988 and 2005, a total of 809 patients were registered in the database, and 16 patients (2%) developed IPT during follow-up. All patients had initial high-grade tumor. Immunostaining for vimentin was positive in all patients, ALK was negative in all patients, and pancytokeratin positive in only 2 patients. During follow-up, 12 patients (75%) developed tumor recurrence, 9 patients (56%) tumor progression, and 6 patients (37.5%) died of bladder cancer. Median period from the finding of IPT to tumor recurrence was 16 months, to progression 7 months, and to mortality 26 months.ConclusionsThe finding of IPT in a patient with a history of bladder cancer is associated with a high risk of tumor recurrence, progression, and cancer-related mortality. Second- and possibly third-look bladder biopsies should be considered. The unique characteristics of IPT in patients with a history of bladder cancer suggest that this is a separate disease entity.