Harrison's Internal Medicine Chapter 90. Bladder and Renal Cell Carcinomas Bladder Cancer A transitional cell epithelium lines the urinary tract from the renal pelvis to the ureter, urinary bladder, and the proximal two-thirds of the urethra. Cancers can occur at any point: 90% of malignancies develop in the bladder, 8% in the renal pelvis, and the remaining 2% in the ureter or urethra. Bladder cancer is the fourth most common cancer in men and the thirteenth in women, with an estimated 67,160 new cases and 13,750 deaths in the United States predicted for the year 2007. The almost 5:1 ratio. | Chapter 090. Bladder and Renal Cell Carcinomas Part 1 Harrison s Internal Medicine Chapter 90. Bladder and Renal Cell Carcinomas Bladder Cancer A transitional cell epithelium lines the urinary tract from the renal pelvis to the ureter urinary bladder and the proximal two-thirds of the urethra. Cancers can occur at any point 90 of malignancies develop in the bladder 8 in the renal pelvis and the remaining 2 in the ureter or urethra. Bladder cancer is the fourth most common cancer in men and the thirteenth in women with an estimated 67 160 new cases and 13 750 deaths in the United States predicted for the year 2007. The almost 5 1 ratio of incidence to mortality reflects the higher frequency of the less lethal superficial variants compared to the more lethal invasive and metastatic variants. The incidence is three times higher in men than in women and twofold higher in whites than blacks with a median age at diagnosis of 65 years. Once diagnosed urothelial tumors exhibit polychronotropism the tendency to recur over time and in new locations in the urothelial tract. As long as urothelium is present continuous monitoring of the tract is required. Epidemiology Cigarette smoking is believed to contribute to up to 50 of the diagnosed urothelial cancers in men and up to 40 in women. The risk of developing a urothelial malignancy in male smokers is increased two- to fourfold relative to nonsmokers and continues for 10 years or longer after cessation. Other implicated agents include the aniline dyes the drugs phenacetin and chlornaphazine and external beam radiation. Chronic cyclophosphamide exposure may also increase risk whereas vitamin A supplements appear to be protective. Exposure to Schistosoma haematobium a parasite found in many developing countries is associated with an increase in both squamous and transitional cell carcinomas of the bladder. Pathology Clinical subtypes are grouped into three categories 75 are superficial 20 invade muscle and 5 are metastatic at .
