Kidney Cancer

The incidence of kidney cancer continues to rise annually. Kidney cancer, specifically renal cell carcinoma (the most prevalent type of cancer that affects the kidneys), begins with the mutation of normal kidney cells. These cancerous cells then begin to multiply at a much faster rate than normal cells would, forming a tumour. Once a renal tumour is large enough, its cells begin to release a substance that promotes the surrounding blood vessels to grow adjacent to the tumour. This process is referred to as angiogenesis. The increased blood supply to the area enables the tumour to continue to grow and increases the risk of metastasis (the spread of cancer to other parts of the body) by carrying free tumour cells from the kidney throughout the rest of the circulatory system. 

Types of Kidney Cancers

The most common kidney cancer is called the renal cell carcinoma (RCC) and is found in the body of the kidney. Renal cell carcinomas can be divided into other sub-categories depending on their characteristics. The sub-categories include clear cell RCC, papillary RCC, chromophore RCC and collecting duct RCC.

Stages of Kidney Cancer

The cancer cells may spread from their original location to other parts in the body. There are different stages of kidney cancer used to classify the progression of the cancer cells.

Stage I: The tumour is only in the kidney and is 7 cm or smaller in size

Stage II: The tumour is only in the kidney and is larger than 7 cm in size

Stage III: The tumour in the kidney is any size and cancer cells have spread to lymph nodes or blood vessels near the kidney

Stage IV: The tumour is in the kidney and cancer cells have spread to fatty tissues, lymph nodes, adrenal glands around the kidney or to other parts of the body (bones, liver, and lung)