The term “cancer” is terrifying for any individual. Recent studies have shown that the burden of cancer is rising each year in India and worldwide. A cancer diagnosis not only changes things for the patient but also for the family. Cancer is generally associated with old age and in most instances to lung or breast. Not many are aware that cancer can also affect an eye, which is relatively a small organ of the body. Eye cancer represents less than 0.5% of all other cancers. However, certain types of eye cancer can be life-threatening, if left untreated. There are three-way effects of eye cancer where it can affect vision, eye, and life. The three main goals of an ocular oncologist when dealing with eye cancer are to save lives, save eyes, and save vision. Eye cancer can affect any age. It is not limited to older individuals only. Eye cancer can affect newborns, infants, young children, middle-aged, or older individuals.
The most common cause of eye cancer in children is Retinoblastoma (a tumour arising in the retina). The burden of retinoblastoma is huge—the largest number of cases reported in India is around 1500 new cases every year. It affects children younger than three years of age. It usually presents as leukocoria or squint. If diagnosed, 95% of the lives can be saved if diagnosed early.
If there is a history of retinoblastoma in one of the parents or a sibling, it is mandatory to have a routine eye examination of the child within 10 days of birth and periodically thereafter. If the cancer is detected early both the vision and life can be restored. When the tumour has advanced locally, the eye may have to be sacrificed in order to safeguard the life, but they can be cosmetically rehabilitated with a customized ocular prosthesis, thereby nurturing their confidence.
A child with one normal eye can still lead a fruitful life doing all routine activities as a child of their age and can attend a regular school with no qualms. If retinoblastoma is left untreated, it spreads to the adjacent brain and the chances of salvaging the life in such cases are minimal.
The most common cause of eye cancer in adults is an ocular surface tumour (tumour over the thin layer of tissue covering the eye), particularly ocular surface squamous neoplasia (OSSN) and an eyelid tumour that affects the sebaceous glands. This tumour mainly occurs due to excessive ultraviolet light exposure and thus is more common in people who are involved in manual labour. It is most common in older patients but can affect younger patients if there is any systemic risk factor. This tumour has very low risk to spread elsewhere in the body, but when extensive it can extend on to the adjacent cornea, into the eye, or behind the eye. The requirement of enucleation (removal of the eye) is extremely rare except in cases with the extension of tumour into the eye or behind the eye.
The other common malignant tumour in adults is sebaceous gland carcinoma. It presents as a painless eyelid nodule which is gradually increasing in size. It is generally yellow in colour and is well appreciated on eyelid eversion. It mainly affects older patients, and sometimes affects middle-aged patients. The treatment of this tumour includes surgical removal and eyelid reconstruction. If left untreated, this tumour has a high potential to spread elsewhere in the body, thus threatening life.
In conclusion, eye cancer is rare compared to other cancers of the body and is a problem that affects all ages. Though rare, they can threaten vision, eye, and life. Early diagnosis is the key to improving the outcomes. There is a need to increase awareness about eye cancers both in the general population and health care professionals. Any mass on the eyelid or ocular surface, unexplained decrease in vision, squint, white reflex in the eye are all signs of eye cancer and warrants an opinion from an ocular oncologist. When eye cancers are detected early, all three goals of treatment of saving lives, eyes, and vision can be achieved.
(The writer is ocular oncologist, head of oncology department L V Prasad Eye Institute)