Urologic emergencies in the cancer patient

Urologic emergencies are common in the cancer patient and relate mainly to complications of bladder hemorrhage, upper or lower urinary tract obstruction, urinary tract infection, and priapism. Hemorrhagic cystitis is commonly due to bladder injury from radiation therapy, viral infection, or metabolites of chemotherapeutic agents. Treatments aimed at ameliorating the effects of theses metabolites, such as mesna and intravenous (IV) hydration, coupled with cystoscopy, evacuation of clots, and formalin instillation, have given clinicians an effective means of avoiding exsanguinating hemorrhage from the bladder. Malignant ureteral obstruction is an ominous sign in the cancer patient and may be due to tumor compression, retroperitoneal adenopathy, or direct tumor invasion. The endourologic procedures of ureteral stenting and percutaneous nephrostomy are effective means of palliation; however, complications of infection, stent obstruction, and stent migration can result in hospital admission and a decline in quality of life. Median survival for patients with malignant ureteral obstruction is less than 7 months, regardless of the tumor of origin. Bladder outlet obstruction leading to urinary retention can be due to mechanical factors involving the bladder neck or prostate, or to a breakdown in the neurophysiologic function of the bladder. Every attempt is made to avoid surgical intervention or the placement of chronic in-dwelling catheter in these often debilitated patients. Patients are often effectively treated with a variety of pharmacologic agents, such as alpha-adrenergic receptor blockers or by the initiation of chronic intermittent catheterization. Urinary tract infections are particularly dangerous in neutropenic and bone marrow transplant patients, with bladder catheters the most common portal entry. The colonization and later infection by resistant nosocomial organisms, such as Pseudomonas aeruginosa and Candida albicans, can rapidly lead to life-threatening sepsis. On rare occasions, emergency surgical intervention with adequate open drainage or nephrectomy is required to control such infections. Priapism can be caused by hematologic malignancy with hypercoagulation, metastatic disease involving the corpora cavernosa with thrombosis of the venous outflow from the penis, or rarely from intracavernous injections used for the treatment of impotence. If effective treatment exists for the primary tumor, improvement or resolution of the state of priapism may occur. Radiation therapy may be required to decrease the pain associated with malignant priapism, but surgical shunting procedures are rarely effective.