Eosinophilic infiltrates in carcinoma of the urinary bladder unassociated with schistosomiasis.

Two hundred and twenty-four biopsies from 151 patients with urinary bladder neoplasms have been studied in order to investigate the incidence of and possible causes for the infiltration of eosinophils. Cases of schistosomiasis were excluded from this study. Of these biopsies, 16 showed a heavy infiltrate 26 a moderate, 61 minimal and 121 no eosinophilic infiltrate. No correlation could be found between the degree of infiltrate and age, sex or tumour type. There was some statistically significant correlation between the eosinophilic infiltrate and stromal invasion and/or tumour necrosis. There was a strong statistical correlation between this infiltrate and previous trauma (biopsy) which was supported by the study of bladder biopsies from patients without neoplasms.