Primary inflammation of the lower urinary tract mainly affects the urinary bladder. There are acute or chronic forms of inflammation. Stranguria, pollakiuria, and hematuria are good indicators for cystitis. Most of the tumors are of epithelial origin. They occur as papillomas, carcinomas, transitional cell carcinomas, squamous cell carcinomas or adenocarcinomas.
Mesenchymal tumors comprise leiomyomas, fibromas, myxomas or their malignant counterparts.
Botryoid rhabdomyosarcoma occurs as a peculiar entity in young large breed dogs. These tumors originate from embryonic myoblasts. Microscopically, the primitive cells are anaplastic. This disease examplifies both inflammation and neoplasia. It occurs in mature cattle and is attributed to prolonged ingestion of bracken fern or other ferns.