Kidney cancer, also known as renal cancer, is a cancer that develops in the kidneys. The real cause of kidney cancer is not known. But abnormal cell growth causes all cancer and it occurs due to changes in the DNA of the affected cells.
Risk factors for kidney cancer can be hereditary factors, obesity, kidney disease, exposure to chemicals like cadmium or benzene, certain genetic conditions like von Hippel-Lindau (VHL) disease and lymphoma.

Symptoms
Kidney cancer symptoms usually do not appear in the early stages of the disease. In the later stages of kidney cancer, the patient may experience one or more of the following symptoms.
â Extreme fatigue
â Blood appearing in urine
â Appetite loss
â Lower back pain
â Unexplained weight loss
â Anemia
â Lump in the abdomen
â Fever that occurs not due to infections but other reasons
â Swollen legs or ankles
â Pain in bones or in the waist or sides

Some kidney cancer symptoms like breathlessness may appear when the disease has spread to other body parts. Depending on the patient’s symptoms, the doctor may order tests such as a biopsy, X-rays, MRI or a CT scan to confirm the diagnosis of kidney cancer.

Treatment
The treatment of kidney cancer depends on the stage of the disease. The stages and the numbers in the stage determine the severity of kidney cancer.

â Stage 1 When the tumor is 7 centimeters in size or smaller and is confined to the kidneys.

â Stage 2 When the cancer is larger than 7 centimeters but still in the kidney.

â Stage 3 When the tumor has spread to nearby parts such as the adrenal gland, one or more of the major veins or a lymph node.

â Stage 4 When the cancer has spread to surrounding tissues or to lymph nodes (more than one) or other body parts.

Another aspect of the kidney cancer staging is the system of TNM, which refers to tumor, node and metastasis.
â T refers to the tumor size (T0 to T4).
â N refers to the presence of kidney cancer cells in one or more lymph nodes (N0 to N2).
â M refers to the spread of kidney cancer to other body parts (M0 to M1).

Stage 4 kidney cancer treatment depends on factors like the severity of the cancer and the health of the patient.
â Surgery is the main treatment for less advanced stages of kidney cancer. For stage 4 kidney cancer treatment, the doctor may plan a surgery along with other types of therapies.
â Additional therapies may include radiation therapy, targeted therapies, biological therapy, chemotherapy, arterial embolization or cryotherapy.
â Biological therapy, also known as immunotherapy, is one of the main stage 4 kidney cancer treatment methods. This therapy is an attempt to strengthen the immune system to effectively fight or stop the spread of cancer cells. Different types of biological therapies use different drugs for the treatment.