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Additional Information
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Bone Cancer: Questions and Answers
- What are bones made of and how do they function?
Mature bones are made up of three types of tissue:
compact tissue (the hard outer portion of most bones);
cancellous tissue (spongy tissue inside the bones that
contains bone
marrow, which makes blood cells);
and subchondral tissue (smooth bone tissue of the joints).
A layer of cartilage covers
subchondral tissue to cushion the movement of joints.
Bones support and protect internal organs,
act as levers and braces for muscles to produce movement,
and produce and store blood cells in the bone marrow.
- Are all bone tumors cancerous?
Bone tumors may
be benign (noncancerous)
or malignant (cancerous).
Benign bone tumors are more common than malignant ones.
Both types may grow and compress healthy bone tissue
and absorb or replace it with abnormal tissue.
However, benign tumors do not spread and are rarely life-threatening.
Cancer that
arises in the bone (primary bone cancer) is not the same
disease as cancer that spreads to the bone from another
part of the body (secondary bone cancer). Primary bone
cancer is rare, with approximately 2,500 new cases diagnosed
each year in the United States. More commonly, bones
are the site of tumors that result from the spread (metastasis)
of cancer from another organ, such as the breasts, lungs,
and prostate.
This fact sheet deals with primary bone cancer.
- What types of cancer arise in the bones?
The most common type of bone cancer is osteosarcoma,
which develops in new tissue in growing bones. Another
type of cancer, chondrosarcoma,
arises in cartilage. Evidence suggests that Ewing’s
sarcoma,
another form of bone cancer, begins in immature nerve
tissue in bone marrow. Osteosarcoma and Ewing’s
sarcoma tend to occur more frequently in children and
adolescents, while chondrosarcoma occurs more often in
adults (see chart).
Cancers of the Bone
| Types of Cancer |
Tissue of Origin |
Common Locations |
Common Ages |
| Osteosarcoma |
Osteoid |
Knees, upper legs, upper arms |
10–25 |
| Chondrosarcoma |
Cartilage |
Pelvis,
upper legs, shoulders |
50–60 |
| Ewing’s
Sarcoma |
Immature nerve tissue,
usually in bone marrow |
Pelvis, upper legs, ribs, arms |
10–20 |
- What are possible risk factors for bone cancer?
Although scientists are
not certain what causes bone cancer, a number of factors
may put a person at increased risk. These cancers occur
more frequently in children and young adults, particularly
those who have had radiation or chemotherapy treatments
for other conditions. Adults with Paget’s disease,
a noncancerous condition characterized by abnormal development
of new bone cells, may be at increased risk for osteosarcoma.
A small number of bone cancers are due to heredity. For
example, children with hereditary retinoblastoma (an
uncommon cancer of the eye) are at a higher risk of developing
osteosarcoma.
- What are the symptoms of bone cancer?
Pain is the most common symptom of
bone cancer. However, symptoms may vary depending on
the location and size of the cancer. Tumors that occur
in or near joints may cause swelling or tenderness in
the affected area. Bone cancer can also interfere with
normal movements and can weaken the bones, occasionally
leading to a fracture. Other symptoms may include fatigue,
fever, weight loss, and anemia.
None of these symptoms is a sure sign of cancer. They
may also be caused by other, less serious conditions.
It is important to check with a doctor.
- How is bone cancer diagnosed?
To diagnose bone cancer, the doctor asks about the patient’s
personal and family medical history and does a complete
medical exam. The doctor may suggest a blood test to
determine the level of an enzyme called
alkaline phosphatase. A large amount of alkaline phosphatase
can be found in the blood when the cells that form bone
tissue are very active—when children are growing,
when a broken bone is mending, or when disease or a tumor
causes production of abnormal bone tissue. Because high
levels of this enzyme can normally be found in growing
children and adolescents, this test is not a completely
reliable indicator of bone cancer.
X-rays can
show the location, size, and shape of a bone tumor. If
x-rays suggest that a tumor may be cancer, the doctor
may recommend special imaging tests
such as a bone
scan, a CT (or CAT)
scan, an MRI,
or an angiogram.
However, a biopsy—the removal of a sample of tissue
from the bone tumor—is needed to determine whether
cancer is present.
The surgeon may
perform a needle
biopsy or an incisional
biopsy. During a needle biopsy, the surgeon makes
a small hole in the bone and removes a sample of tissue
from the tumor with a needle-like instrument. In an incisional
biopsy, the surgeon cuts into the tumor and removes a
sample of tissue. Biopsies are best done by orthopedic
oncologists—doctors experienced in the diagnosis of
bone cancer. A pathologist—a doctor who identifies
disease by studying cells and tissues under a microscope—examines
the tissue to determine whether it is cancerous.
- What are the treatment options for bone cancer?
Treatment options depend on the type, size, location,
and stage of
the cancer, as well as the person’s age and general
health. Surgery is
often the primary treatment. Although amputation of
a limb is sometimes necessary, pre- or post-operative
chemotherapy has made limb-sparing surgery possible in
many cases. When appropriate, surgeons avoid amputation
by removing only the cancerous section of the bone and
replacing it with an artificial device called a prosthesis.
Chemotherapy and radiation may also be used alone or
in combination. Because of the tendency for Ewing’s
sarcoma to metastasize rapidly,
multidrug chemotherapy is often used, in addition to
radiation therapy or surgery on the primary
tumor.
- Are new treatments being studied?
To develop new, more effective treatments, the National
Cancer Institute is sponsoring clinical
trials (treatment studies with cancer patients)
in many hospitals and cancer centers around the country.
Clinical trials are a critical step in the development
of new methods of treatment. Before any new treatment
can be recommended for general use, doctors conduct
clinical trials to find out whether the treatment is
safe for patients and effective against the disease.
Various forms of cancer treatments using surgery, radiation
therapy, and chemotherapy for bone cancer are being
tested in clinical trials.
Patients who are interested in learning more about participating
in clinical trials can call the Cancer
Information Service or access the clinical trials
page of the National Cancer Institute’s Web site
at http://www.cancer.gov/clinical_trials on
the Internet.
To read the rest of this article, and more
about Bone Cancer from the National Cancer Institute, please
click here: http://www.cancer.gov/cancertopics/factsheet/Sites-Types/bone
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