Adamantinoma

Adamantinomas are a rare type of bone cancer that occurs when epithelial tissue (protective tissue that lines the skin and other organs of the body) grows within osseous (bone) tissue. It is most commonly found in in the bones of the lower legs (tibia and fibula), but can also be found in other bones such as the radius (forearm), ulna (forearm), mandible (jaw), or in the bones of the hands and feet. Adamantinomas found in the bones of the lower legs may also be referred to as extragnathic adamantinomas.

Adamantinomas are slightly more common in males, and is most commonly diagnosed between the ages of 10-30. 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, because of how rare adamantinomas are, there is currently no standard staging and grading system for this disease. Instead, your doctor will recommend a treatment plan based on the following factors:

  • Cancer location.
  • Whether or not the cancer has metastasised.
  • Your age.
  • General health.
  • Your treatment preferences.

In general, most adamantinomas are considered to be low-grade (cancer cells present as slightly abnormal and are usually slow growing), and are unlikely to metastasise.

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 adamantinomas may include:

  • Surgery, potentially including:
    • Wide local excision. This option may also be referred to as a limb-sparing surgery.
    • Amputation.
  • Clinical trials.
  • Palliative care.

Unfortunately, this type of cancer does not often respond to chemotherapy and radiation therapy.

Risk factors

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

Symptoms

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

  • Sharp or dull pain in affected area.
  • Swelling of affected area.
  • Redness in affected area.
  • Increased pain with activity or lifting.
  • Limping (if in the leg).
  • Decreased movement of affected area.

In rare cases, the tumour may metastasise to another part of the body, most commonly the lungs. This may cause additional symptoms.

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 a PDS, 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.
    • Bone scan.
    • CT (computed tomography) scan.
    • MRI (magnetic resonance imaging).
  • Blood tests.
  • Biopsy.

References

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