Microscopic changes of the urinary bladder in patients with primary tumors locally treated with Corynebacterium parvum.

The study covered 34 patients with tumors of the urinary bladder treated surgically by transurethral resection and, as an adjuvant therapy, with Corynebacterium parvum intravesically administered. Microscopic observations were performed on smears stained with blue polychrome-tannin and the histologic study used preparata stained with hematoxylin-eosin and van Gieson. After the second series of instillations, many biopsies from the same patient were taken. The investigation revealed the negativity for malignant cells on the cytologically studied smears, and histologically a chronic infiltrate formed of lymphocytes and plasma cells along the basement membrane could be observed; sometimes the infiltrate was follicularly organized. The morphologic changes of the urinary bladder mucosa were correlated with the immunostimulation potential of Corynebacterium parvum.