The kidneys, two bean-shaped organs that filter waste and excess fluid from the bloodstream, are prone to developing kidney cancer. There are various types of kidney cancer, including those affecting one or both kidneys as well as those spreading to the lungs, bones, or liver. Smokers, obese people, and people with high blood pressure are more likely to develop kidney cancer. Surgery, medication, radiation, or other therapies may be used to treat kidney cancer, depending on its stage and type.
There is no known cause for kidney cancer, but it may be caused by changes (mutations) in the DNA of kidney cells. Mutations can cause the cells to grow and divide abnormally, resulting in a tumor. The following factors may increase the risk of developing kidney cancer:
Smoking: Smoking tobacco can damage the DNA of the kidney cells and increase the risk of kidney cancer by about 50%.
Obesity: Being overweight or obese can cause hormonal changes and inflammation that can affect the kidney cells and increase the risk of kidney cancer by about 25%.
High blood pressure: Having high blood pressure can damage the blood vessels in the kidneys and increase the risk of kidney cancer by about 20%.
Family history: Having a close relative with kidney cancer can increase the risk of kidney cancer by about 2 to 4 times.
Genetic syndromes: Having certain inherited conditions, such as von Hippel-Lindau syndrome, Birt-Hogg-Dube syndrome, or hereditary papillary renal cell carcinoma, can increase the risk of kidney cancer by affecting the genes that control the growth and repair of the kidney cells.
Exposure to toxins: Being exposed to certain chemicals, such as asbestos, cadmium, or trichloroethylene, can damage the DNA of the kidney cells and increase the risk of kidney cancer.
Kidney cancer often does not cause any symptoms in the early stages, and may be detected by accident during a routine test or scan. As the cancer grows or spreads, some symptoms that may occur are:
Blood in the urine: The most common symptom of kidney cancer is seeing blood in the urine, which may appear pink, red, or brown. This can be caused by the tumor bleeding into the urinary tract.
Pain in the side or back: Some people may feel pain in the side or back, below the ribs, where the kidneys are located. This can be caused by the tumor pressing on the nerves or organs.
Lump or mass in the abdomen: Some people may feel or see a lump or mass in the abdomen, near the kidney. This can be caused by the tumor growing large enough to be felt or seen.
Weight loss: Some people may lose weight without trying, due to the cancer affecting the appetite or metabolism.
Fever: Some people may have a fever that comes and goes, without any obvious infection or reason. This can be caused by the cancer affecting the immune system or causing inflammation.
Anemia: Some people may have low levels of red blood cells, which carry oxygen in the blood. This can cause fatigue, weakness, or shortness of breath. This can be caused by the cancer affecting the production or function of the red blood cells.
A doctor must ask about the patient's medical history and symptoms, and perform a physical examination, in order to diagnose kidney cancer. The doctor may also order some tests to confirm the diagnosis and determine the type and stage of the disease.
Urine test: To check for blood or other signs of infection or disease in the urine.
Blood test: To check for the levels of creatinine, calcium, red blood cells, and other indicators of kidney function or cancer.
Imaging test: To take pictures of the kidneys and other organs, and look for any tumors or abnormalities. The most common imaging tests are ultrasound, computed tomography (CT) scan, magnetic resonance imaging (MRI) scan, or positron emission tomography (PET) scan.
Biopsy: To take a small sample of the kidney tissue and examine it under a microscope for signs of cancer cells. This can be done by inserting a thin needle through the skin into the kidney, or by removing a small piece of the kidney during surgery.
It depends on the type, stage, and location of kidney cancer as well as the patient's overall health and preferences. There are several main goals of treatment: to eliminate or destroy the cancer, to prevent or delay its recurrence or spread, and to improve the quality of life and survival of the patient.
It is most common to treat kidney cancer with surgery, which involves removing the affected kidney, as well as nearby lymph nodes or organs. Open surgery involves making a large incision in the abdomen or back, while laparoscopic or robotic surgery involves making several small incisions and using instruments and a camera. A kidney cancer that is confined to the kidney can be cured by surgery, but complications, such as bleeding, infection, or kidney failure, may also occur.
An ablation is a procedure in which cancer cells in the kidney are destroyed using extreme heat (radiofrequency ablation) or cold (cryoablation). In addition to inserting a probe into the kidney through the skin, ablation can also be performed by using a special device during surgery. If a person has a small tumor or cannot have surgery, ablation may be an option, but it can also cause complications, such as bleeding, infection, or tissue damage.
Drugs are used to kill or stop the growth of cancer cells. They can be administered by mouth, injection, or infusion. If a person has advanced or metastatic kidney cancer, or can't be operated or ablationated, medication may be an option, but it can also cause side effects, such as nausea, vomiting, fatigue, or rash. Medications for kidney cancer include the following:
Drugs that target specific molecules or pathways involved in the growth and survival of cancer cells. Examples include sunitinib, pazopanib, axitinib, cabozantinib, sorafenib, and lenvatinib.
Nivolumab, ipilimumab, pembrolizumab, and avelumab are examples of immunotherapy drugs for kidney cancer.
Usually used when other treatments have failed or are unsuitable, chemotherapy interferes with the ability of cancer cells to divide and multiply.
In radiation therapy, high-energy rays or particles are used to damage or destroy cancer cells. Radiation can be administered externally or internally. If a patient has advanced or metastatic kidney cancer, or if they experience symptoms such as pain or bleeding, radiation may be an option, but it can also cause side effects such as irritability, fatigue, or nausea.
There is no sure way to prevent kidney cancer, but some measures may help to reduce the risk or detect the cancer early, such as:
Quitting smoking or avoiding exposure to tobacco smoke, which can damage the DNA of the kidney cells and increase the risk of kidney cancer.
Maintaining a healthy weight and a balanced diet, which can prevent obesity and inflammation that can affect the kidney cells and increase the risk of kidney cancer.
Controlling blood pressure and taking medication if needed, which can prevent damage to the blood vessels in the kidneys and increase the risk of kidney cancer.
Avoiding exposure to toxins or chemicals, such as asbestos, cadmium, or trichloroethylene, which can damage the DNA of the kidney cells and increase the risk of kidney cancer.
Getting regular check-ups and tests, such as urine test, blood test, or imaging test, which can detect kidney cancer or other kidney problems early, when they are easier to treat.
