Ocular Surface Squamous Neoplasia (OSSN)

Ocular surface squamous neoplasia (OSSN) is a rare and broad spectrum of tumours that range from benign tumours such as epithelial dysplasia and papillomas, to malignant tumours such as squamous cell carcinomas (SCC) and mucoepidermoid carcinomas. These tumours develop on the ocular surface, which encompasses the cornea and conjunctiva of the eye.

The eye is a sensory organ that allows us to see by reacting to light. Light passes through the cornea (the clear, front layer of the eye) and enters the eye through an opening called the pupil (the black centre of the eye). The amount of light received by the pupil is controlled by the iris (the coloured portion of the eye). This light is then passed through the lens (the clear, inner portion of the eye) and works together with the cornea to focus light onto the retina (a layer of tissue at the back of the eye that is sensitive to light). The retina then activates photoreceptors (image forming cells) to convert the light to electrical impulses that travel to the brain via the optic nerve, which is then converted into an image.

OSSN is more common in males, and tends to be diagnosed around the age of 56. 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 help your doctors determine the best treatment for you. However, because of how rare OSSNs are, there is currently no standard staging and grading system for this disease. Instead of staging and grading, 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.

Your doctor may also 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 options for OSSN may include:

  • Tumour excision.
  • Chemotherapy.
  • Radiation therapy.
  • Immunotherapy.
  • Clinical trials.
  • Palliative care.

Risk factors

While the cause of OSSN remains unknown, the following factors may increase the likelihood of developing the disease:

  • Exposure to ultraviolet (UV) B radiation.
  • Infections with the human papillomavirus (HPV), human immunodeficiency virus (HIV) and/or hepatitis B or C.

Not everyone with these risk factors will develop the disease, and some people who have the disease may have none of these risk factors. See your general practitioner (GP) if you are concerned.

Symptoms

The symptoms of OSSN may include:

  • Fleshy, elevated ocular lesion.
  • Red eye.
  • Irritation of the eye.
  • Inflammation of the eye.
  • Pain in the eye.
  • Vision loss (extreme cases).

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 OSSN, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:

  • Physical examination.
  • Eye tests.
  • Imaging tests, most commonly an ultrasound of the eye.
  • Biopsy.

References

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