Kidney Cancer
Definition
Kidney cancer, renal cancer, is a disease in which kidney cells become malignant (cancerous) and
grow out of control, forming a tumor.
Almost all kidney cancers first appear in the lining of tiny tubes (tubules) in the kidney.
This type of kidney cancer is called renal cell carcinoma
Incidence
The incidence of kidney cancer seems to be increasing. One reason for this may be the
fact that imaging techniques such as computerized tomography (CT) scans are being
used more often.
These tests may lead to the accidental discovery of more kidney cancers. In many cases,
kidney cancer is found at an early stage, when the tumors are small and confined to the
kidney, making them easier to treat.
Kidney cancer is among the 10 most common cancers in both men and women.
Overall, the lifetime risk for developing kidney cancer in men is about 1 in 46 (2.02%).
The lifetime risk for women is about 1 in 82 (1.02%).
Etiology and risk factors
Unknown cause
kidney cancer occurs most often in people older than age 40.
other risk factors for kidney cancer:
Smoking : smoking cigarettes, increases the risk for kidney cancer is twice that of non-
smokers.
Being male: Men are about twice as likely as women to get kidney cancer.
Being obese: Extra weight may cause changes to hormones that increases the risk.
Using certain pain medications for a long time: This includes over-the-counter drugs in
addition to prescription drugs.
Having advanced kidney disease or being on long-term dialysis, a treatment for people
with kidneys that have stopped working
Having certain genetic conditions, such as von Hippel-Lindau (VHL) disease or inherited
papillary renal cell carcinoma
Having a family history of kidney cancer: The risk is especially high in siblings.
Being exposed to certain chemicals, such as asbestos, cadmium, benzene, organic solvents,
or certain herbicides
Having high blood pressure: Doctors don't know whether high blood pressure or
medication used to treat it is the source of the increased risk.
Being black: The risk in blacks is slightly higher than in whites. No one knows why.
Having lymphoma: For an unknown reason, there is an increased risk of kidney cancer in
patients with lymphoma.
Stages
These are the stages of kidney cancer. The higher the stage, the more advanced the
cancer.
I. Stage I
A tumor 7 centimeters or smaller that is only in the kidney
II. Stage II
A tumor larger than 7 centimeters that is only in the kidney
III. Stage III
A tumor that is in the kidney and in at least one nearby lymph node
A tumor that is in the kidney's main blood vessel and may also be in nearby lymph
node
A tumor that is in the fatty tissue around the kidney and may also involve nearby
lymph nodes
A tumor that extends into major veins or perinephric tissues, but not into the
ipsilateral adrenal gland and not beyond Gerota's fascia
IV. 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).
Types
The main types are:
Clear cell carcinoma: This is the most common type, accounting for 70–75% of renal
cell carcinomas. Clear cell renal cell carcinoma (CCRCC) is a renal cortical tumor
typically characterized by malignant epithelial cells with clear cytoplasm and a compact-
alveolar (nested) or acinar growth pattern interspersed with intricate, arborizing
vasculature.
Papillary renal cell carcinoma: Around 10% of renal cell carcinomas are of this type.
Papillary renal cell carcinoma (PRCC), that forms inside the lining of
the kidney's tubules (the very small tubes that do the filtering). Commonly referred to as
“renal cell cancer,” PRCC is the second most common type of kidney cancer.
Chromophobe renal cell carcinoma: This accounts for around 5% of cases. This type of
kidney cancer that forms in the cells lining the small tubules in the kidney.
Other Types
Transitional cell carcinoma: These start in the area where the kidneys meet the ureters.
Around 5–10% are this type.
Wilms tumor: Also known as nephroblastoma, these usually affect children.
Renal sarcoma: These start in the blood vessels or connective tissue of the kidney an
account for around 1% of cases.
Clinical features
In many cases, people may have no early symptoms of kidney cancer. As the tumor grows
larger, symptoms may appear. Patient may have one or more of these kidney cancer
symptoms:
Blood in urine
A lump in side or abdomen
A loss of appetite
A pain in side that doesn't go away
Weight loss that occurs for no known reason
Fever that lasts for weeks and isn't caused by a cold or other infection
Extreme fatigue
Anemia
Swelling in ankles or legs
Kidney cancer that spreads to other parts of your body may cause other symptoms, such as:
Shortness of breath
Coughing up blood
Bone pain
Diagnosis
Physical exam
Health history
Urine tests check for blood in urine or other signs of problems.
Blood tests show how well kidneys are working.
Intravenous pyelogram (IVP)
Ultrasound uses sound waves to create a picture of kidneys. It can help tell if a tumor is
solid or fluid-filled.
A CT scan : CT scans have virtually replaced pyelogram and ultrasound as a tool for
diagnosing kidney cancer.
Magnetic resonance imaging (MRI)
Renal arteriogram: This test is used to evaluate the blood supply to the tumor. It is not
given often, but may help diagnose small tumors.
Renal biopsy
Management
Kidney cancer is one of the more common cancers to undergo spontaneous regression, in
which it may return to an earlier stage. However, the incidence is quite low (approximately
0.5%).
There are several standard types of treatment for kidney cancer. In most cases, surgery is the
first step. Even if surgery removes the entire tumor, though, your doctor may suggest an extra
treatment to kill any remaining cancer cells that can't be seen.
I. Surgery for kidney cancer
These are the main types of surgery for kidney cancer. Which type you have depends on how
advanced cancer is.
Radical nephrectomy removes the kidney, adrenal gland, and surrounding tissue. It also
often removes nearby lymph nodes. It is the most common surgery for kidney cancer and
can now be done through a small incision with a laparoscope.
Simple nephrectomy removes the kidney only.
Partial nephrectomy removes the cancer in the kidney along with some tissue around it.
This procedure is used for patients with smaller tumors (less than 4 cm) or in those
patients in which a radical nephrectomy might hurt the other kidney.
Kidney transplantation
If surgery can't remove kidney cancer, your doctor may suggest another option to help destroy the
tumor.
Cryotherapy uses extreme cold to kill the tumor.
Radiofrequency ablation uses high-energy radio waves to "cook" the tumor.
Arterial embolization involves inserting material into an artery that leads to the kidney.
This blocks blood flow to the tumor. This procedure may be done to help shrink the
tumor before surgery.
II. Biologic therapy for kidney cancer
This therapy uses your immune system to fight cancer by boosting, directing, or restoring
your body's natural defenses. Substances for biologic therapy are made by your body or
in a lab.
Examples of biologic therapy for metastatic kidney cancer include interferon alpha or
interleukin-2. There are many new immunotherapies being actively studied for kidney
cancer.
III. Targeted therapy for kidney cancer
This therapy uses drugs or other substances to find and target cancer cells with less
toxicity to normal cells.
One type of targeted therapy is anti-angiogenic agents. These keep blood vessels from
feeding a tumor, causing it to shrink or stop growing.
Another type of targeted agent is known as multikinase inhibitors or tyrosine kinase
inhibitors. These are oral drugs that block an enzyme pathway which allows cancer cells
to grow.
A third type of targeted therapy is known as m-TOR inhibitors. There are two of these
drugs available, one oral and one by IV. They block a pathway which allows blood
vessels to help tumor cells grow. Each of these drugs has a unique place in the
management of advanced kidney cancer.
IV. Radiation therapy for kidney cancer
Often used to help with symptoms of kidney cancer or in patients who cannot have
surgery, this treatment uses high-energy X-rays or other types of radiation to kill cancer
cells or halt their growth.
V. Chemotherapy for kidney cancer
This therapy uses drugs to kill cancer cells or stop them from multiplying.
Less effective for kidney cancer than for other types of cancer, chemotherapy is
mostly used for a certain type of kidney cancer in which there spindle cells
(sarcomatoid variant).
Prevention
quit smoking
maintain a healthy weight
manage blood pressure
avoid being exposed to harmful chemicals.
Healthy lifestyle
Prognosis
Good prognosis in early stages
clear cell carcinoma has the worst prognosis, and chromophobe renal cell carcinoma the
best, with only 7% of cases going on to affect more distant parts of the body.
Several factors can impact the prognosis for an individual, including:
age
overall health and other conditions they may have
family history
if this is the first diagnosis or a recurrence
the type of cancer and how it responds to treatment
People with a kidney cancer diagnosis had the following chances of surviving at least another
5 years. Survival rates includes:
Localized: 93%
Regional: 69%
Distant: 12%
Overall, for all stages: 75%
Complications
Complications of kidney cancer include:
High blood pressure (hypertension)
Too much calcium in the blood.
High red blood cell count.
Liver and spleen problems.
Spread of the cancer.
