Bone and Soft Tissue Tumors: Malignant Tumors
Fibrosarcoma
On this page:
What is a fibrosarcoma?
What causes fibrosarcoma?
What are the symptoms of fibrosarcoma?
How is fibrosarcoma diagnosed?
How is fibrosarcoma staged?
Treatment for fibrosarcoma
What is the long-term outlook for patients with fibrosarcoma?
What is a fibrosarcoma?
A fibrosarcoma is a malignant (cancerous) tumor that originates in the connective fibrous tissue found at the ends of bones of the arm or legs, and then spreads to other surrounding soft tissues. Soft tissues include fat, muscles tendons (bands of fiber that connect bones to muscle) nerves, joint tissue, blood vessels and other fibrous tissue. It most commonly affects either a lower leg or arm. There are generally two forms of this disease:
- Infantile or congenital fibrosarcoma: this type of tumor is the most common soft tissue sarcoma found in children under one year of age. It presents as a rapidly growing mass at birth or shortly after. This form of fibrosarcoma is usually slow-growing, and tends to be more benign than fibrosarcoma in older children, which behaves more like the type found in adults.
- Adult form fibrosarcoma: The adult form of this disease can occur in older children and in adolescents, roughly between the ages of 10 and 15. It is more aggressive than the infantile form and generally involves more complex treatment.
What causes fibrosarcoma?
The exact cause of fibrosarcoma and other soft tissue tumors is not entirely understood, however, studies have indicated that genetic alterations may play a role. Researchers have studied a small number of families that contain several members from one generation who have developed soft tissue sarcomas. In addition, limited studies have shown a possible link between soft tissue sarcomas and the development of other types of cancer. A chromosomal rearrangement has been found in some fibrosarcomas.
What are the symptoms of fibrosarcoma?
The following are the most common symptoms of fibrosarcomas. However, each child may experience symptoms differently. The symptoms of fibrosarcoma vary depending on size, location and spread of the tumor. Symptoms may include:
- a painless or tender mass in an extremity or trunk
- pain or soreness caused by suppressed nerves and muscles
- limping or other difficulty using legs, feet, arms or hands
The symptoms of fibrosarcoma may resemble other conditions or medical problems. Always consult a physician for a diagnosis.
How is fibrosarcoma diagnosed?
In addition to a complete medical history and physical examination of your child, diagnostic procedures for fibrosarcoma may include:
- Multiple imaging studies of the tumor and sites of possible metastasis, such as:
X-ray – a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film. X-rays are very useful in the diagnosis of bone tumors and frequently X-rays allow the physician to distinguish between benign and malignant tumors. An X-ray is usually the first diagnostic study and it often gives the doctor information regarding the need for further testing.
Magnetic resonance imaging (MRI) – a diagnostic procedure that uses a combination of large magnets, radio frequencies, and a computer to produce detailed images of organs and structures within the body.. This test is used to assess the size and extent of the mass and its relationship to surrounding muscle, bone, nerves and blood vessels.
Computerized tomography scan (also called a CT or CAT scan) – a diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays. They are used primarily to assess the chest and lung for metastatic tumors.
Bone scan – a nuclear imaging method used to detect bone and metastatic tumors. It can determine if there are abnormalities in other bones. This test does not distinguish between tumor, infection or fractures.
- complete blood count (CBC) – a measurement of size, number, and maturity of different blood cells in a specific volume of blood.
- blood tests (including blood chemistries)
- biopsy of the tumor – a small tissue sample of the tumor is surgically removed. The appearance of the tumor under a microscope establishes the diagnosis and distinguishes a fibrosarcoma from other sarcomas. Biopsy also helps doctors determine how aggressive the tumor is.
How is fibrosarcoma staged?
Once fibrosarcoma has been diagnosed, the tumor is staged. This process indicates how far the tumor has spread from its original location. The stage of a tumor suggests which form of treatment is most appropriate, and gives some indication of prognosis.
A fibrosarcoma may be localized, meaning it has not spread beyond the bone where it arose or beyond nearby tissues, or metastatic, meaning it has spread to lungs, bones other than the bone that the tumor originated in, or to other organs or structures of the body. Tumors found during infancy are usually not metastatic.
Treatment for fibrosarcoma
Specific treatment for fibrosarcoma will be determined by your child's physician based on:
- your child's age, overall health, and medical history
- extent of the disease
- your child's tolerance of specific medications, procedures, or therapies
- how your child's physician expects the disease may progress
- your opinion or preference
Surgery
Surgery may be all that is indicated for an infant with this condition, and limb-sparing surgery is often opted for, rather than amputation, since a local recurrence of congenital fibrosarcoma is not believed to worsen a child's prognosis. Radiation (explained further below) is not generally used for tumors in the extremities because it may interfere with proper bone growth.
Chemotherapy (also discussed below), which is very effective on this type of tumor, may be used in infants if appropriate and resection of the tumor with wide surrounding margins of healthy tissue is not possible.
Older children with this condition are more likely to undergo a combination of surgery, chemotherapy and/or radiation treatment.
Surgery for fibrosarcoma involves the biopsy, surgical removal of the tumor, bone/skin grafts, limb salvage procedures, amputation, and/or reconstruction, all performed by a surgeon. The type of surgery will depend on the size and location of the tumor, and whether the cancer has spread.
Types of Surgery
- Limb-salvage surgery – It is sometimes necessary to remove all or part of a limb. In most cases, however, limb-sparing surgery, sometimes referred to as limb-salvage surgery, is used to avoid amputation. This however is considered only if the orthopedic surgeon determines that it is possible to remove the tumor along with wide margins of healthy tissue surrounding the tumor. Through limb-sparing surgery, all of the tissues involved with the tumor, including some degree of muscle surrounding it, is removed, while nearby tendons, nerves and vessels are saved. If bone is removed, it is replaced with a bone graft or with a metal rod. Subsequent surgery may be needed to repair or replace rods, which can become loose or break. Patients who have undergone limb-salvage surgery need intensive rehabilitation. It may take as long as a year for a patient to regain full use of a leg following limb-salvage surgery. Some patients who have this operation may eventually have to undergo amputation. Radiation therapy and/or chemotherapy (usually not needed in treatment of infants) are given either before surgery to shrink the tumor, or after surgery to kill remaining cancer cells.
- Amputation – In certain cases, if your child's orthopedic surgeon determines that the tumor cannot be removed because, for example, it involves the nerves and blood vessels, amputation is the only option. During the operation, doctors ensure that muscles and skin form a cuff around the amputated bone. A cast is applied in the operating room which permits a temporary artificial leg (prosthesis) to be applied during the first few post-operative days for walking. Crutches are used for several weeks. As the swelling decreases (10 to 14 days), the patient is fitted for a plastic, temporary socket and prosthesis, which is used for three to four months until the stump is healed sufficiently to accept a permanent artificial leg.
The advantages of an amputation are that it is a simple operation with minimal chances of surgical complication and it definitively removes the local tumor. The functional outcome is good with the modern prostheses available today and with "immediate-fit" prostheses applied in the operating room. Although the patient will probably have a limp with above-the-knee amputations, the procedure is functional and stable. He/she will be able to walk, climb stairs, swim (with the prosthesis on or off) and participate in many sports such as skiing, basketball, baseball, and tennis although running will be limited. The functional limitations are left to the imagination and determination of the patient.
Chemotherapy
Chemotherapy is a drug treatment that works by interfering with the cancer cell's ability to grow or reproduce. Different groups of drugs work in different ways to fight cancer cells and shrink tumors. Chemotherapy may be used alone for some types of cancer or in conjunction with other therapy such as radiation or surgery. Often, a combination of chemotherapy drugs is used to fight a specific cancer. Certain chemotherapy drugs may be given in a specific order depending on the type of cancer it is being used to treat. While chemotherapy can be quite effective in treating certain cancers, the agents do not differentiate normal healthy cells from cancer cells. Because of this, there can be many adverse side effects during treatment. Being able to anticipate these side effects can help the care team, parents, and child prepare, and, in some cases, prevent these symptoms from occurring, if possible.
Chemotherapy is systemic treatment, meaning it is introduced to the bloodstream and travels throughout the body to kill cancer cells. Chemotherapy can be given:
- as a pill to swallow
- as an injection into the muscle or fat tissue
- intravenously (directly to the bloodstream; also called IV)
- intrathecally (chemotherapy given directly into the spinal column with a needle)
Radiation Therapy
Radiation uses high-energy rays from a specialized machine to damage or kill cancer cells and shrink tumors.
Rehabilitation
Rehabilitation includes physical and occupational therapy and psychosocial adapting.
Supportive care
Supportive care refers to any type of treatment to prevent or treat infections, side effects of treatments, and complications, and to keep your child comfortable during treatment.
Continuous Follow-Up Care
A schedule of follow-up care will be determined by your child's physician and other members of your care team to monitor ongoing response to treatment and possible late effects of treatment.
What is the long-term outlook for patients with fibrosarcoma?
Prognosis for fibrosarcoma greatly depends on:
- the extent of the disease
- the size and location of the tumor
- presence or absence of metastasis
- the tumor's response to therapy
- the age and overall health of the child
- your child's tolerance of specific medications, procedures, or therapies
- new developments in treatment
