About Kidney Cancer

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Clinical care and treatment services for kidney cancer at UCLA is facilitated through the UCLA Kidney Cancer Program. Click to the tabs above to learn more about kidney cancer, and you can learn more about UCLA kidney cancer care services for both patients and healthcare professionals with the quicklinks below.

What is Kidney Cancer?

According to the American Cancer Society, over 60,000 people in the United States were estimated to have been diagnosed with kidney cancer in 2014, and over 13,000 people will die from this disease. The majority of patients diagnosed with kidney cancer are over the age of 45, with the highest incidences between the ages of 55 and 84.

Unfortunately, kidney cancer is often diagnosed at a late stage because the tumors can become quite large without causing any symptoms or pain and because the kidneys are located deep inside the body and there is no means of seeing or feeling small tumors on the kidneys during a physical exam.

Types of Kidney Cancer

It is important to understand that with timely diagnosis and treatment, kidney cancer can be cured. If found early, the survival rate for patients with kidney cancer ranges from 79 to 100 percent. There are over 100,000 survivors of kidney cancer alive in the United States today. The following iinformation addresses the most common types of kidney cancer and is meant to serves as a supplement to the discussions you have with your physician.

Renal Cell Carcinoma (RCC)

Renal Cell Carcinoma (RCC) is the most common type of kidney cancer, accounting for approximately 85 percent of all malignant kidney tumors. In RCC, cancerous (malignant) cells develop in the lining of the kidney tubules and grow into a mass called a tumor. Like many other cancers, the growth begins small and grows larger over time. RCC typically grows as a single mass. However, there are cases where a kidney may contain more than one tumor, or tumors are found in both kidneys at the same time.

There are five main types of renal cell carcinoma that are identified by examining the tumor under a microscope:

  • Clear Cell RCC is the most common form of renal cell carcinoma, accounting for about 80 percent of people with kidney cancer. When viewed under a microscope, the individual cells that make up clear cell renal cell carcinoma appear very pale or clear.
  • Papillary RCC is the second most common type. About 10 to 15 percent of people have this form. These cancers form little finger-like projections (called papillae).
  • Chromophobe RCC accounts for about five percent of cases. Like clear cell carcinoma, the cells of these cancers are also pale, but are much larger and have certain other distinctive features.
  • Collecting Duct RCC is the rarest form of RCC. The major characteristic of collecting duct RCC is that the cancer cells can form irregular tubes.
  • Unclassified RCC, or about 5 percent of renal cancers, are unclassified because their appearance does not fit into any of the other categories.

Transitional Cell Carcinoma

About 5 to 10 percent of all kidney tumors are transitional cell carcinomas, also known as urothelial carcinomas. Transitional cell carcinomas begin in the renal pelvis (the junction of ureter and kidney). Under the microscope, transitional cell carcinomas look like bladder cancer cells and act very much like bladder cancer. Studies have shown that, like bladder cancer, these cancers are linked to cigarette smoking and occupational exposures to certain cancer-causing chemicals.

About 90 percent of transitional cell carcinomas of the kidney are curable if they are found early enough. The chances for cure drop dramatically if the tumor has grown into the ureter wall, or if it has a more aggressive (high-grade) appearance when viewed under the microscope.

Wilms Tumor

About five to six percent of all kidney cancers are Wilms tumors. This type of cancer is almost always found in children and is extremely rare among adults.

Renal Sarcoma

Renal sarcomas are a rare type of kidney cancer (less than one percent of all kidney tumors) that begins within the kidney's connective tissue.

Benign (Non-Cancerous) Kidney Tumors

Some types of kidney tumors (including renal cell adenomas, renal oncocytomas and angiomyolipomas) do not usually spread (metastasize) to other parts of the body, although they can still grow and cause problems.