Kidney Cancer

Kidney
Cancer

---

Each year, 36,000 Americans are diagnosed with
kidney cancer. The vast majority of these patients
su?er from renal cell carcinoma, a malignancy
in the tissue cells where blood is ?ltered into
urine. Most kidney cancers are primary tumors
meaning they originate in the kidney rather than
spreading from other areas of the body. They
can still be deadly if not found early and treated
aggressively.
Fortunately, urologists—doctors who specialize
in diseases of the male and female urinary tracts
and the male reproductive system—have e?ective
ways today to diagnose and treat kidney cancer,
especially if it is caught early. Imaging tests
that involve little or no discomfort for patients
allow physicians to pinpoint these malignancies
with accuracy, e?ciency and relative speed.
Similarly, because of advances in techniques
and technology, surgeons can now eliminate
the malignancy by either removing all or part of
the kidney. If they catch the tumor before it has
spread, patients have a ?ve- to 10-year cancer
survival rate of at least 90 percent. Obviously, this
rate decreases if the tumor has spread.
The path to a cure for kidney cancer, however,
starts with information. This pamphlet is
designed to help you understand this disease,
know the symptoms and be able to discuss your
options with your physician.
2

---

KIDNEY
cancer
WHAT ARE THE KIDNEYS

AND HOW DO THEY WORK?
The kidneys are the body’s waste treatment plant.
Fixed to the back wall of the abdominal cavity,
to the left and right of your backbone, these
bean-shaped, ?st-sized organs ?lter the blood of
any excess water, salt and other wastes. Working
together, they convert products into a liquid
called urine. It travels from the kidneys through
narrow tubes called ureters to the bladder where
it is stored temporarily until exiting the body
through the urethra during urination. While the
kidneys are essential to your good health, you do
not need both of these organs to keep your body’s
?uids and electrolytes in balance by eliminating
wastes. You can function with one compensating
for the missing other. In fact, dialysis, a blood-
washing technique that removes toxins from the
body, allows thousands of people to live with less
than one working kidney.
WHAT CAUSES KIDNEY CANCER?
Like other malignancies, kidney cancer begins in
the cells, the basic building blocks of your body’s
tissues and organs. Under normal circumstances,
cells grow and divide, reproducing as you need
them. But in cancer, this orderly process goes
haywire. Even when new cells are not called for,
existing ones replicate aggressively, eventually
forming a mass called a tumor. Sometimes
1

---

these tumors invade nearby tissue or spread
(metastasize) through the bloodstream to other
organs where they develop secondary tumors.
Scientists believe that damage to DNA, the
genetic substance inside the cell that drives all
of its biologic activity, is behind this cascade of
events. But they are just beginning to understand
how genes, the individual segments of DNA
and chromosomes, change to make kidney cells
cancerous.
FAMILIAL KIDNEY CANCER
Some of these mutations are passed from one
generation to the next. Accounting for 3 to 4
percent of all cases, familial kidney cancer a?ects
people with a family history of either cancer or
certain rare genetic disorders linked to it. People
with conditions such as von Hippel-Lindau (VHL)
MALE
Front view,
interior of male
urinary system
KIDNEYS
URETERS
BLADDER
PROSTATE
URETHRA
PENIS
Jennifer Fairman. All rights reserved.
2

---

KIDNEY
cancer
tend to develop tumors earlier in life (before 50).
They also may su?er multiple tumors, a?ecting
both kidneys and possibly other organs as well.
If you have a family history of kidney cancer or a
disease related to it, you should be followed closely
with regularly scheduled appointments and exams.
You may also want to undergo genetic testing for
one of the known genetic traits that can lead to
kidney cancer. Doctors now have sophisticated
ways to screen people for syndromes associated
with this cancer. The most important ?rst step,
however, is to provide as much information as
possible to your doctor about other cancers and
medical issues in your family.
SPORADIC KIDNEY CANCER
Most kidney cancer is sporadic. It occurs for
reasons other than an inherited mutation. Instead
FEMALE
Front view,
interior of female
urinary system
KIDNEYS
URETERS
BLADDER
URETHRA
Jennifer Fairman. All rights reserved.
3

---

of passing through the family, the cell changes
occur long after birth, possibly due to cancer-
causing chemicals or other outside risk factors.
While scientists do not know all of the sources, they
suspect certain lifestyle and job-related triggers are
at work. They include:
• Cigarette smoking. Tobacco increases the chance
of developing kidney cancer by about 40 percent,
making it perhaps the major risk factor for this
disease. Scientists believe that many of the cancer-
causing chemicals in smoke, which are absorbed
into the bloodstream, actually settle in large
concentrations in the kidneys during ?ltering.
Several of these substances are known to damage
kidney cell DNA, possibly causing a tumor to
form. Once a person stops smoking, however, the
kidneys are no longer exposed to those chemicals.
The risk drops, even though it takes many years to
reach the level of a non-smoker.
• Workplace hazards. Many studies indicate
that people exposed to chemicals (e.g., asbestos,
cadmium, some herbicides, benzene, lead and
organic solvents such as trichloroethylene) in
their jobs have a higher risk of kidney cancer than
others without such occupational hazards.
• Obesity, high blood pressure and a sedentary
lifestyle. Taken separately or combined, these
factors add up to an increased risk for kidney
cancer. Several studies have shown, for instance,
that inactive adults are more likely to develop a
kidney tumor than people who exercise regularly.
Some physicians suspect that obesity is a factor in
4

---

KIDNEY
cancer
20 percent of kidney cancer cases. It alters the
body’s balance of hormones, which a?ects the
normal (and abnormal) growth of kidney tissue.
Other statistics suggest that excess weight, in
combination with high blood pressure, triples
the risk.
• Kidney disease. Patients with advanced kidney
disease have an increased risk of developing
kidney cancer, especially if they undergo long-
term dialysis. While the process cleans toxins
from the blood of people whose kidneys do not
work properly, it is related to a slightly raised
incidence of kidney cancer.
WHAT IS RENAL CELL CARCINOMA?
Several di?erent kidney cancers can occur in
adults, but renal cell carcinoma (adenocarcinoma)
comprises almost 90 percent of all cases. It involves
several cell types, all derived from the parenchmya,
the kidney tissue that ?lters urine. There are
several types of renal cell carcinoma that can be
identi?ed under a microscope. No matter what cell
type, all renal cell carcinomas can be successfully
treated with surgery if the tumor is contained. If it
has spread, treatments vary.
WHAT ARE SOME OTHER TYPES OF

KIDNEY CANCER?
• Transitional cell carcinoma. Accounting for
5 to 10 percent of all kidney tumors, it forms
in the lining of the renal pelvis, the funnel-like
area of the kidneys where urine collects before
passing down the ureters into the bladder.
5

---

• Wilms tumor. Also known as nephroblastoma,
accounts for about 5 to 6 percent of all kidney
tumors. It is the most common kidney cancer
found in children; yet it is extremely rare in
adults. It is linked to certain birth defects or
syndromes.
• Renal sarcomas. Comprising less than 1
percent of all kidney tumors, these rare masses
begin in the connective tissue of the kidney.
Not all kidney tumors are life threatening
(malignant). Some (e.g., renal adenoma,
oncocytoma and angiomyolipoma) are relatively
harmless (benign). They usually can be removed
and seldom come back. They also do not invade
other tissues or parts of the body. However, they
can still grow and cause problems so they need to
be addressed.
WHAT ARE THE SYMPTOMS OF

KIDNEY CANCER?
Kidney cancer rarely causes symptoms in its
earliest stages. Many cases are detected by chance
during routine evaluation by imaging studies
for an unrelated problem. The disease may also
show up during regular screening in high-risk
patients. Since there is no speci?c blood test to
catch a kidney cancer tumor early, it can become
quite large before it is actually found. The ?rst
symptoms you may experience are:
• blood in the urine (hematuria)
• low, one-sided back pain
• mass or lump in the abdomen
6

---

KIDNEY
cancer
• fatigue
• unexplained weight loss
• unexplained fever
• swelling of the ankles and legs (edema)
Most of the time, these signs do not mean cancer.
They can indicate a cyst, infection or other benign
problem. But if you have symptoms, contact
your health care provider. When kidney tumors
are diagnosed and treated early, they are usually
treated successfully.
HOW IS KIDNEY CANCER

DIAGNOSED?
Kidney cancer is diagnosed based on symptoms,
a physical examination and various tests. If you
have complaints that suggest this type of cancer,
your doctor will perform:
• Physical examination. You will be asked ?rst
about your family and personal health histories
to review any risk factors or symptoms for this
disease. The doctor will then check your vital
signs (e.g., blood pressure and temperature) to
assess your general health. He or she will also
feel your abdomen and side for any masses or
tumors.
• Urinalysis. A sample of your urine will be
taken for microscopic and chemical analysis.
Laboratory tests are used to ?nd tiny bits of
blood and other substances that are not seen by
the naked eye but may indicate kidney cancer.
Cytology is also used to locate cancer cells
present in the urine. Some patients with kidney
7

---

cancer do not have blood in their urine until the
tumor is large and may even have spread. But
blood can also indicate other benign conditions
such as urinary tract and bladder infections,
which require prompt treatment to keep them
from becoming more serious.
• Blood tests. Your doctor can evaluate the
function of your kidney and other organs
through a complete blood count (CBC) and
other chemical tests. Measuring white cells,
red cells and platelets, a CBC can detect signs
of kidney cancer, including anemia (too few red
blood cells) and erythrocytosis (too many red
blood cells.) A high level of substances such as
creatinine, also can mean the kidneys are not
working well.
• Fine needle aspiration. Unlike other
malignancies, kidney cancer is usually
diagnosed without a biopsy. Imaging studies
generally provide su?cient detailed information,
but your doctor may still want to examine the
cells if the imaging studies are inconclusive.
During a biopsy, small pieces of tissue or ?uid
are removed with a needle inserted through the
skin into the kidney. A pathologist examines
the sample under a microscope to identify the
presence of any malignant cells.
Your doctor has several radiographic tests from
which to choose in diagnosing your cancer:
• Intravenous pyelogram (IVP). Known also
as urography, this test uses a special contrast
8

---