Osteofibrous Dysplasia (OFD)

Osteofibrous dysplasia (OFD), also known as ossifying fibroma of the long bones, is a very rare and benign type of bone tumour that occurs when osseous tissue (bone tissue) is replaced by fibrous tissue (tissue that makes up tendons and ligaments) in a bone. OFD is most commonly found in the bones of the lower legs (tibia and fibula), but can also be found in other bones such as the humerus (upper arm), radius (forearm), ulna (forearm), clavicle (collarbone), or mandible (jaw).

OFD is generally diagnosed equally among the sexes, and is most commonly found in children under 10 years old. However, anyone can develop this disease.

Treatment

When cancers are detected, they are staged and graded based on size, metastasis, and how the cancer cells look under the microscope. Staging and grading helps your doctors determine the best treatment for you. However, as most OFDs are considered benign, these tumours are generally considered low-grade and not staged.

Once your tumour has been diagnosed, your doctor may recommend genetic testing, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you. Treatment is dependent on several factors, including location, age, stage of disease and overall health.

Treatment options for OFD may include:

  • Surgery, potentially including:
    • Surgical excision.
    • Curettage.
    • Bone graft.
    • Extraperiosteal excision (this is then treated with a bone graft or a prosthesis to fill the hole).
  • Bone brace.
  • Clinical trials.
  • Palliative care.

Risk factors

Because of how rare OFD is, there has been limited research done into the risk factors of this disease.

Symptoms

Many patients with OFD appear asymptomatic in the early stages of disease. As the tumour progresses, some of the following symptoms may appear:

  • Pain and/or swelling in affected area.
  • Easily broken bones.
  • Limb bowing (when the legs curve outwards at the knees while the feet and ankles touch).

Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.

Diagnosis

If your doctor suspects you have an OFD, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:

  • Physical examination.
  • Imaging tests, potentially including:
    • X-ray.
    • MRI (magnetic resonance imaging).
    • CT (computed tomography) scan.
  • Blood tests.
  • Biopsy.

References

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