What is kidney cancer?
Kidney cancer is cancer that begins in the kidneys, which are organs that lie in the back of the abdomen, behind the bowels. The kidneys are the main filters of the body. They filter out waste products and carcinogens (cancer causing substances), transferring them from the bloodstream into the urine. These undesirable substances can then be eliminated from the body. Another common name of kidney cancer is renal cell carcinoma (RCC), Renal refers to the kidney and carcinoma is another name for cancer.
Cancer is an uncontrolled growth of cells that eventually become large enough to make a tumor. Normal cells divide only when needed to replace other cells that are dying, and this process is very tightly regulated. Cancer cells have mutations that allow them to divide out of control, they body is often unable to stop this process. The tumor cells also become resistant to the natural cycle of growth and cell death (also known as apoptosis), and they just keep growing.
Cancer cells also secrete certain proteins (proteases) that can digest the surrounding tissue, allowing the cells to invade adjacent areas. The tumor cells can then spread to other parts of the body; this is known as metastasis. The tumor cells can also stimulate new blood vessels to grow toward them to provide nutrients and oxygen for continued growth. This is known as angiogenesis— without angiogenesis the tumor cells would starve or remain dormant (inactive). A cancer must be able to do most or all of these things to metastasize, to cause pain, or to kill a patient. Unfortunately, some kidney cancers have this potential. Tumors that cannot invade locally or metastasize are benignâ€”these can grow, but rarely cause trouble and can often be left untreated.
Kidney cancer has always been relatively unresponsive to chemotherapy, which is somewhat unique in the cancer world. The main hope for most kidney cancer patients is that cancer can be removed surgically— kidney cancer is still primarily a surgical disease. However, thanks to the work of dedicated researchers and clinicians, better treatments are now available for all stages of kidney cancer, even for patients with more advance disease that cannot be removed surgically. New treatments that block the blood vessels supplying tumors with nutrients and oxygen can starve the tumor and slow or reverse its growth. These treatments, known as anti-angiogenic treatments, are now creating great excitement for the treatment of patients with kidney cancer and have moved kidney cancer to the forefront of modern oncology.
Causes of kidney cancer
The causes of kidney cancer are not fully understood. It is known that smokers are twice as likely as nonsmokers to develop kidney cancer. Some researchers estimate that cigarette smoking is linked o 30% of kidney cancers in men and 24% in women. One researcher estimated that more than 80% of renal pelvis cancer in men and more than 60% in women would be prevented if people stopped smoking.
Another possible cause of kidney cancer is exposure to chemicals, both produced by the body and inhaled to digest. Because the kidneys filter waste, they are exposed to many chemical substances. Heavy, long-term use of the analgesic phenacetin is associated with renal pelvis cancer. The risk is 19 times greater for smokers who use phenacetin. The Food and Drug Administration banned phenacetin- containing products in 1983.
Occupational exposure is another possible cause. Some studies suggest that coke oven workers and insulation workers have a above-average rate of the disease. Reports show that workers in the rubber, leather, petroleum, dye, textile, and plastic industries have an increased risk of kidney cancers.
There is also evidence that obesity may increase the risk of developing kidney cancer. Several studies show an increased risk among women, and at least one report says obese men may also be at risk.
Women treated with radiation therapy, particularly for problems in the uterus, are at a greater risk. Patients exposed to thorium dioxide, a radioactive substance used in the 1920s with certain X-rays (no longer used), have an increased rate of renal cell carcinoma.
Signs and symptoms of kidney cancer
Most persons with kidney cancer are asymptomatic until disease is advanced. The classic-triad of symptoms includes (1) blood in the urine (haematuria), which is the most common symptoms, (2) flank pain, (3) and a palpable abdominal mass. A significant number of persons have nonspecific symptoms such as weight loss, anemia, fatigue, intermittent fever, and hypertension.
Diagnosis of kidney cancer
Diagnosis of kidney cancer mainly include
- Blood and urine tests
- Intravenous pyelogram (IVP)
- Ultrasound scan
- Computed tomography (CT) scan
- CT- guided biopsy
- Magnetic resonance imaging (MRI) scan.
Treatment of kidney cancer
If the disease is diagnosed and treated at an early stage, kidney cancer can often be cured. Surgery is the most common treatment for kidney cancer. Depending on the stage of the disease and overall health situation of a patient, several surgical options can be applied When the tumor is small and confined to a certain portion of the kidney, only part of the kidney and the adrenal gland, or even the surrounding tissue, may have to be removed if the cancer has spread over a large area. In some cases, hormonal treatment or biological treatment can be used either after surgery or when a cancer cannot be removed surgically. Occasionally radiation therapy is used. In rare cases, kidney cancer spontaneously improves without any treatment.