Kidney cancer happens when cells in one or both kidneys grow abnormally and out of control. Eventually, the cells form a lump called a tumor. As cancer gets worse, it can spread to other parts of the body.
This article will cover kidney cancer, its types, symptoms, causes, how it's diagnosed, and treatment options.
Kidney structure and function
The kidneys are bean-shaped organs. There are two, one on each side of the spine behind the belly organs. Each is about the size of a small fist.
Some people have only one kidney, which can be due to a birth defect or disease. You can live fine with one kidney as long as it works properly.
The kidneys remove minerals Waste and salts andwater The kidneys filter about 150 liters of blood and produce about 1-2 liters of urine daily.
Urine passes through tubes called ureters to the bladder, where it's stored until you pee. The filtering units in the kidney are called nephrons, with over a million in each kidney. Inside the nephron there's a structure called the glomerulus that acts as a filter, plus a tubule that removes waste and returns important stuff to the blood.
Types of Kidney Cancer
There are many types of kidney cancer, These types include:-
1. Renal cell carcinoma
Renal cell carcinoma is the most common form of kidney cancer, making up about 85% of diagnosed kidney cancer cases.
2. Transitional cell carcinoma
Transitional cell carcinoma makes up about 5% to 10% of kidney cancers. It starts from the cells involved in bladder cancer. Transitional cell carcinoma is often treated more like bladder cancer than renal cell carcinoma.
3. Wilms tumor
Wilms tumor is a cancer that usually develops in childhood. Among childhood cancers, it's relatively common.
4. Renal sarcoma
Renal sarcoma is a rare tumor that often starts in the connective tissue of the kidney.
Since renal cell carcinoma is the most common type of kidney cancer, most of the info in this article is about it. This cancer is thought to start in the tubules of the nephron.
Kidney cancer symptoms
Kidney symptoms usually don't show up until the disease is advanced. When symptoms do happen, they may include the following:-
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Blood in the urine, either after peeing or seen under a microscope.
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A lump on the side or lower back (flank lump).
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Feeling pain in the side or lower back (flank area).
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Fever.
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Unexplained weight loss.
Causes of kidney cancer
The exact causes of kidney cancer are not known yet, but researchers have identified several risk factors that increase the chance of getting kidney cancer. Some of these factors include:
- Age: The risk of kidney cancer goes up with age. Most kidney cell cancer cases happen in people over 40. Wilms tumor is most common in kids.
- Gender: Kidney cancer is more common in men than in women.
- Smoking - People who smoke are more likely to get kidney cancer.
- WorkExposure at work to certain stuff like asbestos and benzene ups the risk of kidney cancer.
- Obesity.
- Family History - Having a family history or some genetic syndromes raises the risk of kidney cancer.
- Medications - Using some drugs like calcium channel blockers can increase the risk of kidney cancer.
How to diagnose kidney cancer
Symptoms might be the first clue to kidney cancer in people. Kidney cancer often gets found during imaging tests for other issues, like X-rays, CT scans, or MRIs.
When a healthcare provider suspects kidney cancer, they can use a CT scan to check the kidneys. This test combines many X-ray images into a 3D picture of the inside of the body. It uses iodine contrast dye injected into a vein, which helps the internal structures show up better. It can also help tell cancer apart from non-cancerous cysts.
CT scans can find kidney cancer, show its stage, the tumor size, and if it has spread to other parts of the body.
Some people can’t have a CT scan, maybe because of allergies to contrast dye or kidney problems. These people might get an MRI instead. MRI is also helpful if the tumor has spread into veins near the kidneys.
Also, a biopsy lets healthcare providers look at cells under a microscope. This can be very helpful to guide the right treatment. Unlike many tumors, a biopsy isn’t always needed to diagnose kidney cancer.
Stages of kidney cancer
If kidney cancer is diagnosed, more tests might be needed to see if the cancer spread to nearby tissues or organs. Kidney cancer stages are classified by measuring the tumor size inside the kidney structures.
Kidney cancer stages include the following:-
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Stage One:- Stage one kidney cancer includes a tumor no bigger than 7 cm, only in the kidney.
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Stage Two:- Stage two kidney cancer involves tumors bigger than stage one, but still only in the kidney.
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Stage Three:- Stage three kidney cancer means the cancer has spread to nearby tissues or blood vessels.
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Stage four: Stage four kidney cancer means the cancer has spread beyond the kidney's outer lining and may have spread to nearby organs.
Kidney Cancer Treatment Options
Kidney cancer is a bit unique because surgery is possible even with advanced tumors. Also, targeted therapies and immunotherapy drugs can be used. Chemo and radiation play a smaller role than in some other cancers.
Treatment depends on the cancer stage and other factors. For example, the patient's overall health and the tumor's location in the kidney help guide treatment choices.
Treatment options include:
1. Surgery
Most people with kidney cancer will have some kind of surgery. Those with early-stage kidney cancer are the best candidates for surgery. Kidney cancer is also one of the few solid tumors where surgery can help even in advanced metastatic disease (stage four).
2. Targeted Therapy
Many targeted therapy drugs have been approved for some people with advanced kidney cancer. These drugs help stop cancer cells from growing and spreading by directly interfering with the pathways that support cancer growth. They may also block blood vessels that feed the tumor.
3. Immunotherapy
Immunotherapy, also called biological therapy, works by boosting the body's immune system to fight cancer cells. Some types of this therapy are especially effective for treating kidney cancer.
4. Radiotherapy
Radiotherapy is usually not used as a treatment for kidney cancer. It can be used to ease symptoms when the cancer starts to spread.
5. Chemotherapy
Chemotherapy only has limited effect against some types of kidney cancer, though it's more effective against transitional cell cancer and Wilms tumor.
In the end, it's important to know the possible symptoms and risk factors of kidney cancer, since this can help catch it early if someone has it, giving them more treatment options.
