kidney cancer

The definition of a tumor is a mass of cells growing rapidly and abnormally. The tumors can be benign or malignant. Benign tumors have uncontrolled cell growth, but not in normal tissue invasion and without any spread. A malignant tumour is called cancer when these tumor cells win the propensity to invade tissues and spread locally as well as distant parts of the body. In this sense, kidney cancer occurs when cells in both cortex of the kidney or cells of the renal pelvis and grow uncontrollably to form tumors that can invade normal tissue and spread to other parts of the body.

Cancers are described by the types of cells from which they arise. Again, to discuss kidney cancer, renal cortex and pelvis should be mentioned separately. In the kidney cortex, the majority of cancers result from the cells that line collecting tubules, more specifically, the proximal tubules. Cânceres that develop from coating like this are called carcinomas. In this case, they are, of course, called renal cell carcinoma. More than 75% of renal cell carcinomas are called clear cell carcinomas, named after the characteristics they display when looking at them under the microscope. Other rankings, in descending order of prevalence include chromophilic, chromophobic, oncocytic, and collecting duct cancers. However, it appears that these different types of renal cell carcinoma differ in presentation or prognosis.

Cancers of the renal pelvis, or cord, are uncommon. Over 90% of cancers that develop in the renal pelvis are called transitional cell carcinomas. They are so named because they develop from cells that line of the renal pelvis and upper ureters.