Cancer of the kidney—also called renal cell cancer, kidney adenocarcinoma or hypernephroma—accounts for about 2.5 percent of new cancers in the United States, 27,600 cases a year. Unfortunately, five-year survival rates have not changed for the past 30 years, partly because two-thirds of these cancers are not localized in the kidney when they are diagnosed. About 11,300 persons will die of kidney cancer in 1994.
Kidney tumors do not lend themselves to early diagnosis since these organs lie deep in the body between the lining of the body cavity (peritoneum) and the back muscles at the level of the last two ribs. By the time symptoms such as back pain and bloody urine are noted, the tumor is large (average size is 3 in. or 7.5 cm), has invaded lymph nodes and/or surrounding structures and is very vascular because of its ability to attract blood vessels. This increased vascularity soon leads to spread to the lungs, liver and bone. Five-year survival ranges between 50 to 80 percent for small tumors within the kidney that can be completely removed by surgery, whereas high-grade advanced disease invading lymph nodes, inferior vena cava or adjacent and distant organs has a cure rate of only 5 to 45 percent.
Renal cancer arises from the outer portion of the kidney called the parenchyma (as opposed to the renal pelvis, which briefly collects the urine, which is then carried by a tube, the ureter, to the bladder for storage
