Cancer starts when cells in the body change (mutate). These changes allow them to start growing out of control. Cancer cells can form lumps of tissue called tumors. They can spread to other parts of the body, too. Cancer that starts in the cells that make up the kidney is called kidney or renal cancer.
Understanding the kidneys
The kidneys are 2 bean-shaped organs about the size of a fist. They're found in the low back. There's 1 kidney on each side of the spine.
The kidneys make hormones that help control blood pressure and the number of red blood cells in the body. They also filter blood to take out waste, salt, and extra fluid. They send this liquid and waste (urine) to the bladder through tubes called the ureters. Urine then leaves the body through another tube called the urethra.
When kidney cancer forms
Kidney cancer starts when cells that make up the kidney change or mutate. These cells don't work the way they should and grow out of control. Over time, this can change the way the kidney works. Kidney cancer often starts in 1 kidney. But sometimes it's in both kidneys.
Kidney cancer may spread beyond the kidney to other parts of the body, like the bones, liver, lungs, or brain. This spread is called metastasis. The more cancer spreads, the harder it is to treat.
Treatment choices for kidney cancer
You and your healthcare provider will decide on a treatment plan that's best for you. Treatment choices may include:
This is the most common treatment for kidney cancer. It may be advised if any of these apply to you:
You're healthy enough to have surgery. Your provider will only suggest surgery if you're expected to be able to recover from it.
The tumor is small. In this case, a partial nephrectomy might be done. Only the part of the kidney that has the tumor is taken out. This allows you to keep some function in that kidney. This surgery might also be used if the tumor is larger, but you have cancer in both kidneys or you have only 1 kidney. The benefit is that you keep part of your kidney. The risk is that there's a chance some cancer cells might be left behind.
The tumor is larger, but the cancer is only in your kidney. The type of surgery you need is based on the size of the tumor and where it is. A simple nephrectomy may be an option. This is surgery to take out the whole kidney. A person can function with only 1 kidney. Sometimes a radical nephrectomy is needed. This surgery takes out the whole kidney and the adrenal gland. (There's an adrenal gland on the top of each kidney.) Much of the nearby fatty tissue is also taken out. Nearby lymph nodes will likely be removed, too (called lymph node dissection). This is because cancer tends to travel to the lymph nodes first. Taking them out may help prevent the spread of cancer to other parts of your body. Testing these lymph nodes for cancer helps your provider figure out the stage of the cancer. This is important in deciding if you need other treatments after surgery.
The kidney cancer has spread, but your providers believe that removing the original kidney tumor will still be useful along with other treatment. A radical nephrectomy and removal of nearby lymph nodes might be done. Any tumors in other parts of your body may also be removed. Or you may get other treatment. Even when surgery won’t cure the cancer, it can sometimes help ease symptoms such as pressure, pain, or bleeding.
You have symptoms, like pain, pressure, or bleeding, from tumors that have spread. Surgery may be done to remove the tumors. This can help ease symptoms. But it doesn't cure the cancer. This is called palliative therapy .
These medicines help your immune system better fight the cancer. They work like the chemicals that your body’s immune system makes. This treatment is sometimes called biologic therapy.
These therapies use medicines that target genes or proteins found mostly in or on the cancer cells. Targeted therapy can help keep the cancer cells from growing and spreading to other parts of the body.
Chemotherapy (chemo) uses medicines to kill cancer cells. But chemo doesn't often work well for kidney cancer. Because of this, it's mostly been replaced by targeted and immunotherapy for kidney cancer treatment. But chemo is sometimes used for certain types of kidney cancer.
Radiation therapy uses strong beams of energy to kill cancer cells. Radiation therapy doesn't work as well as other options for treating kidney cancer. But it may be used to treat someone who's not healthy enough to have surgery.
Most often, radiation is used to treat problems caused by metastatic kidney cancer. For instance, it might be used to treat kidney cancer that's spread to the bone (bone metastasis). It can also help stabilize a bone that's been weakened by metastasis and may be at risk for breaking.
Local treatment (ablative therapy)
Ablative treatments are used to destroy the tumor in the kidney. Experts don’t know how well these treatments work over time. But they may be helpful if a person isn’t well enough to have surgery.
These treatments are done by putting a needle-like probe through your skin and right into the tumor. A CT scan or ultrasound is used to help put the probe in the right place. In radiofrequency ablation (RFA), an electric current is sent through the probe to kill the cancer cells. Cryoablation is done by sending very cold gas through the probe to freeze the cancer cells. Medicines are used to make you sleep and not feel pain during these treatments.