Revised April 2000

Bone and Connective Tissue Sarcomas

Overview

Sarcomas are growths which come from primitive cells seen in the human embryo. These cells have the ability to turn into the so-called connective tissues of the body. The tumours are named for the tissue type which they most resemble. For example, tumours that resemble bone-producing cells are called osteosarcoma; those looking like fat cells are called liposarcoma.

Many other types of sarcomas have descriptive names because they do not resemble any specific cell type - alveolar soft parts tumour or Phylloides tumours of breast or prostate. Sarcomas can occur in any part of the body and in total make up less than 1% of all cancers.

Sarcomas are divided into two main groups because of similarities in presentation and treatment:

1. Sarcomas of the bone, bone marrow, and cartilage

• Myelomas, leukemias and lymphomas are cancers of the bone marrow, which are discussed in their own sections
• Other cancers not originally starting in the bone are considered under the section dealing with the type of cancer that was first diagnosed - e.g. breast cancer spread or metastasized to bone is discussed in the breast cancer section

2. Soft tissue sarcomas

1. Bone and Cartilage

General Information/ Anatomy/ Function/ Statistics

• Different types of bone sarcomas appear to favour different age groups. Many kinds of primary bone sarcomas are more common in people under 20, in particular osteosarcoma and Ewing's sarcoma, also known as peripheral neuroectodermal tumours (PNET)
• Primary bone cancers make up less than one half of one percent of all cancers. It is more common for other types of cancer to spread to bone
• Bone sarcomas can occur in any bone in the body but commonly involve bones around the knee and shoulder

Symptoms/ Signs

• Bone pain is the most common problem causing the patient to see a doctor - although specific complaints vary
• Progressing pain and/or swelling and fever may occur
• Pain may be worse at night
• Pain may be relieved by rest/ not putting weight on the affected limb
• Symptoms are similar to those of injuries, bursitis, arthritis or benign bony tumours, so diagnosis is difficult

Etiology/ Carcinogens/ Risks

• Sarcomas are more common in patients and families with abnormalities of so-called tumour suppressor genes, e.g. the retinoblastoma (Rb) gene seen in patients with retinoblastoma or with the p-52 (p-glycoprotein) gene seen in some families. At this time we can account for less than 10% of all cancers as being directly related to genetic abnormalities
• Other predisposing factors include fibrous dysplasia and familial endochondromatosis
• Radiation may be related to the development of some bone sarcomas in people who have received high doses of x-rays or nuclear radiation
• In older patients, a possible contributing factor to developing bone sarcoma is Paget's disease, a benign bone condition occurring mainly in the elderly. Parts of the skeleton become overactive and break down. They simultaneously rebuild themselves at an abnormally fast rate. Areas badly affected by Paget's disease may develop osteosarcoma

Prevention

• None known

Diagnosis/ Staging/ Grading/ Types

• Plain x-ray of painful or symptomatic area
• Chest x-ray
• Computerized tomography scan (CT or CAT scan) of affected bone
• Magnetic resonance imaging (MRI) scan of affected bone
• Computerized tomography (CT) scan of lung
• Core needle biopsy or an open biopsy is often performed using CT scan or ultrasound localization, and under the guidance of the cancer surgeon, to obtain the tissue sample to make the final diagnosis
• Bone scan with x-rays of the abnormal areas
• Patients who are diagnosed with rhabdomyosarcoma or Ewing's sarcoma/ peripheral neuroectodermal tumour (PNET) also have a bone marrow biopsy as part of their routine staging procedures

Types of Bone Sarcomas*

*Note: the tumours are divided into groups named for the tissue type the sarcoma cells most closely mimic, as seen in the table above.

Treatment

• Complete surgical removal of the tumour is the most important treatment
• Many high grade (more rapidly growing) bone tumours are treated with chemotherapy in addition to surgery

Osteosarcoma and Malignant Fibrous Histiocytoma (MFH) of Bone

• Osteosarcoma is the most common type of bone tumour found in children and young adults. It is minimally more common in males than females
• MFH is a rare malignant tumour of bone. It seems to affect older adults but may affect younger persons as well. In some situations, one can demonstrate MFH arising out of osteosarcoma
• These two types of tumours are generally treated in the same way
• These tumour types seem to share common sensitivities to chemotherapy agents. The cause of these tumours is not yet known
• Both tumours can spread locally and by the bloodstream to mainly the lungs or other bones
• Standard treatment involves both surgery and chemotherapy. Current surgery and chemotherapy approaches are showing dramatic improvements in the range of 65% - 70% of patients surviving more than five years
  • The surgery, to widely remove the cancer, is usually done with immediate re-construction of the part of the bone being removed or amputated. Amputation is recommended if the vital structures in the limb, e.g. arteries and nerves and growth plates in children, cannot be spared or reconstructed to remove the tumour completely after wide excision
  • Chemotherapy is used to stop the development of metastasis (distant spread of the tumour) to the lung and other organs
• Radiation is rarely used as primary treatment

Ewing's Sarcoma or Peripheral Neuroectodermal Tumour (PNET)

• Ewing's sarcoma/ PNET are more common in childhood
• Can commonly occur up to the age of 30, but may be seen even in the 60s
• May occur in either bone or soft tissue - treatment is similar
• Standard treatment employs chemotherapy to prevent development of metastatic disease, external radiation, and/or surgery. The whole treatment is about one year in duration
• More than 50% of patients survive five years
• High dose chemotherapy and stem cell transplant may be used in patients with Ewing's sarcoma/ PNET that has spread distant from the primary location

Chondrosarcoma

• Chondrosarcoma is a cartilage-growing tumour that arises in the bone
• Tends to occur in middle-aged individuals
• Bone swelling and pain are most common symptoms
• Tumours rarely require radiation or chemotherapy
• A highly malignant variant, mesenchymal chondrosaroma may be treated like osteosarcoma with chemotherapy and surgery as initial therapy

Chordoma

• Rare tumour arising at the end of the spinal cord or near the base of the skull
• Pain in the region at the end of the spinal cord is most typical for those tumours in that region
• Tumours growing at the base of the skull produce symptoms that involve the cranial nerves, most commonly the nerves of the eyes
• Symptoms may last for many months before diagnosis is clear
• Tumours grow very slowly and spread by local invasion
• Generally treated by surgery and radiation because of their location

Myeloma, Lymphoma

• See Myelomas and Lymphomas

2. Soft Tissue Sarcomas

General Information/ Anatomy/ Function/ Statistics

• These tumours form in the soft tissues of the body - that is, the tissues outside the bones
• Can occur anywhere in the body
• They occur mostly in two groups: young children and young adults onward
• Soft tissue sarcomas tend to spread locally, and via the bloodstream to the lungs
• In sarcoma patients, it is very important to know whether it has been spread to distant parts of the body

Symptoms/ Signs

• Painless lump growing in muscle or under the skin is usually the first symptom
• May be slow to increase in size
• Weight loss and fever

Etiology/ Carcinogens/ Risks

• In most cases, there is no cause which can be identified
• Sarcomas are more common in patients and families with abnormalities of so-called tumour suppressor genes, the p-52 (p-glycoprotein) gene
  • At this time we can account for less than 10% of all cancers as being directly related to genetic abnormalities
• Previous radiation exposure and/or chemotherapy can increase risk
• Some chemical exposures can increase risk

Prevention

• None known

Diagnosis/ Staging/ Grading/ Types

• Plain X-rays of the area near the tumour
• Plain X-ray of the chest
• Magnetic resonance imaging (MRI) scan of the affected area
• Computerized tomography (CT) scan of the affected area
• Lung CT
• Core needle biopsy or open incisional biopsy is preferred, but very small tumours may be excised for diagnosis. Biopsies are generally done by the attending surgeon with guidance by a radiologist using CT or ultrasound scans for localization
• Diagnosis may be evident from regular microscopic examination of the tissue obtained at biopsy, or it may be necessary to do special analyses on the biopsy tissue looking for:
  • specific characteristics with special stains;
  • genetic re-arrangements in the tumour cells and/or products of such genetic changes in the tumour cells; and
  • changes in the cell structure using electron microscopy
• A bone scan is done for patients with rhabdomyosarcoma or soft tissue variants of Ewing's/ peripheral neuroectodermal tumour (PNET) routinely and in cases where other imaging suggests that a bone in the area may be involved
• Patients who are diagnosed to have rhabdomyosarcoma or Ewing's sarcoma/ PNET also have a bone marrow biopsy as part of their routine staging procedures
• Surgery for cure may be offered to some patients with lung metastases

Types of Soft Tissue Sarcomas*

*Note: the tumours are divided into groups named for the tissue type the sarcoma cells most closely mimic, as seen in the table above.

The list above does not include all soft tissue sarcoma types, but does include the most common types.

Treatment

• Complete surgical removal of the tumour is the most important treatment
• Treatment is similar for most soft tissue sarcomas but in some cases, choice of treatment is affected by location and size
• Radiation therapy to the operative site, particularly for high grade (quickly growing) tumour, may be recommended to decrease the chance of tumour recurrence. Otherwise radiation therapy is rarely used in treating soft tissue sarcomas
• Prognosis varies with type, size, location(s) and grade of the tumour
• Average five year survival is 60% after surgery
• Local recurrences may decrease chance of cure
• If the sarcoma has spread beyond the original site, it is unusual to cure the patient except for rhabdomyosarcoma or Ewing's/ PNET where chemotherapy and sometimes stem cell (e.g. bone marrow) transplantation may be useful. Surgery may be offered to some patients with lung metastases

Fibrosarcomas

• Most frequent in patients between 50 and 70 years

Liposarcomas

• May be large fatty tumours - though large size does not necessarily predict for aggressive behavior
• Do not arise from benign fatty tumours (lipomas), which are very common
• Most common in patients between 40 and 60 years
• A very aggressive round cell variant may be treated with adjuvant chemotherapy along with surgery and radiation

Rhabdomyosarcomas (also discussed under Childhood Cancer section)

• Most common soft tissue sarcoma of childhood: 2 to 6 years
• Can spread quickly by bloodstream to distant parts of the body
• Generally divided into subtypes:
  • Embryonal - generally a disease of childhood, occurring in the head, neck and eye
  • Embryonal botryoid - again occurring in children but in the genito-urinary tract
  • Embryonal alveolar - affecting children and young adults, occurring often in muscles of arms and legs
  • Adult pleomorphic or anaplastic - occurs in older patients, generally in muscles of arms and legs
• Usually managed with surgery, radiation and chemotherapy

Leiomyosarcomas

• Tumours commonly arise in the uterus or the smooth muscle of  blood vessels

Angiosarcomas and Lymphangiosarcomas

• Arise in vascular tissue or lymphatics, respectively
• Very malignant types of tumours because these cancer cells spread easily into the bloodstream
• Lymphangiosarcoma may be seen in patients with chronic lymphedema of whatever cause

Synovial Cell Sarcomas

• Usually arise in tissue adjacent to, but not directly from, joints, especially around joints in the lower limbs
• These tumours do not look like cells of the synovium of the joint, but are given this name because of this tumour location - usually near joints
• These tumours, as with other soft tissue sarcomas, can occur anywhere in the body, even in the heart
• Occasionally may spread to the skin, notably the scalp
• Lymph nodes are involved infrequently

Neurofibrosarcoma

• May arise in patients with neurofibromatosis
• Typically a lesion will continue to grow beyond the usual size and may cause pain or dysfunction

Malignant Fibrous Histiocytoma

• One of the more common types of sarcomas
• In superficial sites such as the skin, may behave in a very benign fashion despite high grade-(fast growing)-looking cells
• May be very high grade (fast growing) especially when deep in body cavities or muscles

Kaposi's Sarcoma

• See the separate Kaposi's Sarcoma section

Gastrointestinal Stromal Tumour (GIST)

• Previously was called leiomyosarcoma of the gastrointestinal tract but now believed to be related to the cells controlling normal bowel contractions
• Often is very well differentiated, but may be very hard to prevent local recurrence even with as wide an excision as possible
• Spreads to liver first rather than lungs

Ewing's Sarcoma or Peripheral Neuroectodermal Tumour (PNET)

• Ewing's sarcoma/ PNET are more common in childhood
• Can commonly occur up to the age of 30, but may be seen even in the 60s
• May occur in either bone or soft tissue, for which treatment is similar
• Standard treatment employs chemotherapy to prevent development of metastatic disease, external radiation, and/or surgery. The whole treatment is about one year in duration
• More than 50% of patients survive five years
• High dose chemotherapy and stem cell transplantation may be used in patients with Ewing's sarcoma/ PNET that has spread distant from the primary location

March 2007 We are currently reviewing and updating these pages. If you have any questions about your cancer and its treatment, please discuss with your oncologist or physician. Thank you.