Kidney cancer, also called renal cancer, is a disease in which kidney cells become malignant (cancerous) and grow out of control, forming a tumour. Most kidney cancers first appear in the lining of tiny tubes (tubules) in the kidney and is called renal cell carcinoma. Renal cell carcinoma is the most common type of kidney cancer accounting for almost 90% of cancerous tumours in the kidney. Usually most of kidney cancers are detected before they spread (metastasize) to distant organs and hence are easier to treat. However, these tumours can grow to be quite large before they are detected.
The two most prevalent types of kidney cancers are:
- Renal cell carcinoma (RCC)
- Urothelial cell carcinoma (UCC) of the renal pelvis
RCC and UCC develop in different ways, which means that the diseases have different outlooks and need to be staged and treated in different ways. While RCC is responsible for majority of primary renal cancers, and UCC accounts for the most of the remainder
Kidney cancer rarely causes signs or symptoms in its early stages. In the later stages, kidney cancer signs and symptoms may include:
- Blood in the urine, which may appear pink, red or cola coloured
- Lump in the side of the abdomen.
- Back pain just below the ribs that doesn’t go away
- Persistent pain in the abdomen
- Loss of appetite
- Weight loss
- Extreme fatigue
- Heavy sweating
- Swelling in the ankle of legs
- Fever that lasts for weeks and is not caused by cold or any infection
Kidney cancer which has spread to other parts of the body could have symptoms such as:
- Shortness of breath
- Coughing up blood
- Pain in the bone
However, many of these symptoms can be caused by other conditions as well, and there may also be no signs or symptoms in a person with kidney cancer, especially in the early stages of the disease. It is good to consult a doctor if an individual suffers from multiple of these symptoms.
The exact causes of kidney cancer are unknown as of now. However, there are certain factors that appear to increase the risk. These are:
- Smoking, which can double the risk of the disease
- Regular use of NSAIDs such as ibuprofen and naproxen, which may increase the risk by 51%
- Genetic anomaly or mutations
- Obesity increases the risk of kidney cancer
- A family history of kidney cancer
- Having kidney disease that needs dialysis
- Being infected with Hepatitis C
- Previous treatment for testicular cancer or cervical cancer
- Older age – Your risk of kidney cancer increases as you age.
- Obesity – People who are obese have a higher risk of kidney cancer than do people who are considered average weight.
- High blood pressure (hypertension) – High blood pressure increases your risk of kidney cancer.
- Von Hippel-Lindau disease – People with this inherited disorder are likely to develop several kinds of tumours, including, in some cases, kidney cancer.
- Exposure to certain kind of substances in the workplace such as cadmium or specific herbicides.
- Hereditary papillary renal cell carcinoma – Having this inherited condition makes it more likely for an individual to develop one or more kidney cancers.
Tests and procedures used to diagnose kidney cancer include:
- Blood and urine tests – Tests of your blood and your urine may give your doctor clues about what’s causing your signs and symptoms.
- Imaging tests – Imaging tests allow your doctor to visualise a kidney tumour or abnormality. Imaging tests might include ultrasound, computerised tomography (CT) or magnetic resonance imaging (MRI).
- Removing a sample of kidney tissue (biopsy) – In certain cases, your doctor may recommend a procedure called biopsy to remove a small sample of cells from a suspicious area in the kidney. The sample is tested in a lab to look for signs of cancer.
Unlike most other cancers, the doctor could be certain about a diagnosis of kidney cancer without a biopsy. Often a biopsy will be done to confirm the diagnosis. A doctor may use a needle biopsy to remove a sample of tissue, which is then examined under a microscope for cancer cells. The biopsy may also tell the grade of the cancer and how aggressive the cancer is likely to be. Often the surgeon simply removes the entire tumour and then have a sample of tissue examined.
Once the doctor makes a diagnosis of kidney cancer, other tests maybe required to confirm if the cancer has spread within the kidney, to the other kidney, or to other parts of your body. When cancer spreads from the place where it first started, it is said to have metastasized. A CT scan or an MRI or a chest X-ray can show the extent of the spread. A bone scan can see if it has spread to the bones. These tests will help your doctor determine the stage of kidney cancer. The prognosis on the general health of the patient and the stage of kidney cancer. The higher the stage, more advanced is the cancer:
- Stage I: A tumour 7 centimetres or smaller that is only in the kidney and has not spread
- Stage II: A tumour larger than 7 centimetres that is only in the kidney and has not spread.
- Stage III:
- A tumour that is in the kidney and in at least one nearby lymph node
- A tumour that is in the kidney’s main blood vessel and may also be in nearby lymph node
- A tumour that is in the fatty tissue around the kidney and may also involve nearby lymph nodes
- A tumour that extends into major veins or perinephric tissues, but not into the ipsilateral adrenal gland and not beyond Gerota’s fascia
- Stage IV:
- Cancer has spread beyond the fatty layer of tissue around the kidney, and it may also be in nearby lymph nodes
- Cancer may have spread to other organs, such as the bowel, pancreas, or lungs
- Cancer has spread beyond Gerota’s fascia (including contiguous extension into the ipsilateral adrenal gland)
The treatment suggested by your doctor depends on the stage of kidney cancer. Once the patient is examined the treatment procedure is chosen for the patient which could be any of the following methods:
Surgery is the initial treatment for the majority of kidney cancers. The different types of surgical methods used by the doctors are as below:
- Nephrectomy: Radical nephrectomy involves the removal of the kidney, a border of healthy tissue and the adjacent lymph nodes. The adrenal gland may also be removed.
Nephrectomy can be an open operation, meaning the surgeon makes one large incision to access your kidney. Or nephrectomy can be done laparoscopically, using several small incisions to insert a video camera and tiny surgical tools. The surgeon watches a video monitor to perform the nephrectomy.
- Nephron-sparing surgery: During this procedure, also called partial nephrectomy, the surgeon removes the tumour and a small margin of healthy tissue that surrounds it, rather than removing the entire kidney.
Nephron-sparing surgery is a common treatment for small kidney cancers. It may also be an option if you have only one kidney. When nephron-sparing surgery is possible, it’s generally preferred over radical nephrectomy since retaining as much kidney tissue as possible may reduce your risk of later complications, such as kidney disease and the need for dialysis.
Kidney cancer that recurs and kidney cancer that spreads to other parts of the body may not be curable, but may be controlled with treatment. In these situations, treatments may include:
- Surgery to remove as much of the kidney tumour as possible: Even when surgery cannot remove all of the cancer, it may be helpful in removing a large chunk. Surgery may also be used to remove cancer that has spread to another area of the body.
Biological therapy: Biological therapy (immunotherapy) uses the body’s immune system to fight cancer.
Targeted therapy: Targeted treatments block specific abnormal signals present in kidney cancer cells that allow them to proliferate.
Radiation therapy: Radiation therapy uses high-powered energy beams, such as x-rays, to kill cancer cells. Radiation therapy is sometimes used to control or reduce symptoms of kidney cancer that has spread to other areas of the body, such as the bones.