Intraocular Melanoma or Eye Cancer or Ocular Melanoma in layman terms is a rare form of cancer where the uncontrolled proliferation of the cancerous cells happens in the eye tissues. The eye consists of 3 layers, the outer layer includes the ‘white sclera’ or the ‘white of the eye’ and the cornea. The middle layer is known as ‘uvea’ or ‘uveal tract’ and includes the iris (the coloured part of the eye), the ciliary body (a muscle in the eye), and the choroid (a layer of tissue in the back of the eye). The innermost layer of the eye is called the ‘retina’. Also Read: Oral Cancer: Causes, Symptoms And Treatment
It is the middle part, i.e. the uvea or uveal tract which contains pigment-producing cells called melanocytes where the cancer cells develop. The cancer cells growing in the melanocytes are called melanoma. In most cases, eye melanoma is asymptomatic and hard to detect when looked through the mirror. However, as the tumour enlarges, blurry vision, retinal detachment, glaucoma and some other ocular deformity. Ocular melanoma can either directly happen in the eye tissue or they can spread from another part of the body and reach the eye. Also Read: Seeing Floating Objects? Get Tested For Retinal Detachment
The exact causative factor of eye cancer is still not known but it usually happens when there is an error in the DNA strand of a healthy eye. The error in the DNA causes unhealthy cells to grow and proliferate instead of dying as in the normal case. Overtime these mutated abnormal cells accumulate in the eye to form a malignant tumour.
The various risk factors of intraocular melanoma include:
The risk of eye cancer increases with growing age.
Skin Colour: A white-skinned person with a lower concentration of melanin in their skin are more prone to eye cancer.
Colour Of The Eye: People having blue, green or other light-coloured eyes are more at risk.
Genetic Mutation: It can be hereditary and happen when certain genes are passed from the parents to the children.
Underlying Skin Disease: People with abnormal skin pigmentation or suffering from the dysplastic nervous syndrome are more at risk of getting eye cancer.
Exposure To Harmful Sunrays: Excessive exposure to UVA and UVB light can also increase the risk of eye melanoma.
If the abnormal proliferation of cells in the eye is not stopped or treated on time, it can get complicated and lead to glaucoma, complete loss of vision or spread on to other underlying vital organs.
Although it may take time for the general signs and symptoms to come up, intraocular melanoma is usually characterized by the following indications:
- Dark spot on the iris
- Blurred vision
- Flashes of light or wiggly lines in front of the eyes or at the back of the eye
- Change in size and shape of the pupil
- Change in position of the eyeball in the socket
- Loss of peripheral vision
- Bulging of one or both eyes
Diagnosis And Treatment
It is strictly advisable to consult a doctor as soon as you notice any of the above-mentioned symptoms to start treatment at the earliest. The ophthalmologist usually performs a series of eye examination to look for enlarged blood vessels that might indicate the presence of a tumour. He may also perform tests like:
- Eye Tests including Ophthalmoscopy, Slit-lamp biomicroscopy, Gonioscopy
- Fluorescein Angiography
- Indocyanine Green Angiography
- Optical Coherence Tomography
To determine the stage of cancer or how much it has spread, the doctor incorporates the following tests which include:
- Chest X-ray
- Blood Test: To analyse liver and kidney functions
- Imaging techniques like Ultrasound, MRI-scan, PET-scan, CT-scan etc.
Stages Of Intraocular Melanoma:
Stage 0: There are no reported tumours.
Stage1: Formation of tumour only in the iris
Stage 2: Growth of tumour in the choroid or ciliary body.
Stage 3: Spread of the cancerous tumour from the choroid into the sclera
Stage 4: Tumour becomes more than 5mm in size and spreads outside the eyeball.
Just like any other carcinoma, treatment and recovery from intraocular melanoma are possible if the cancer is diagnosed at an early stage so as to stop the abnormal growth of cells from spreading further. Depending upon the particular stage the patient is diagnosed with, the various treatment options include:
- Radiation therapy
- Laser Treatment
- Photodynamic Therapy
- Cryotherapy or Cold Treatment