 |
        |
| |
| | |
What is Retinoblastoma?
Retinoblastoma (reh-tin-oh-blast-oma) is the most common cancer of the eye among children and is responsible for over 5 per cent of the blindness among children in India. With a rate of incidence of one in 15,000 infants, India has one of the largest numbers of retinoblastoma patients in the world. If left untreated, the disease can cause death. Worldwide 87% of the children stricken with this disease die- mostly in developing countries
When does it strike?
This cancer arises from immature retinal cells in one or both eyes and it can strike from the time a child is in the womb up to 5 years of age. While success rates for treatment are high, early diagnosis and intervention is critical.
How does Retinoblastoma Develop?
Retinoblastoma starts in the retina. Eyes develop very early, even in the womb. During the early stages of development, eyes contain cells called retinoblasts, which grow rapidly until about the fifth year. Later, they stop growing and mature into retinal cells. Rarely does something go wrong in this process. But when some retinoblasts continue to grow rapidly and out of control they become cancerous.
If the growth of these cells is not controlled, they can form a tumour that fills much of the globe (eyeball). The cells may break away from the retinal tumour and float through the vitreous to reach other parts of the eye and form more tumours. If these tumours block the channels through which the fluid in the eye circulates, the pressure inside the eye can rise, resulting in glaucoma, which leads to the loss of vision in the affected eye. Glaucoma is one of the serious complications of retinoblastoma.
Most often retinoblastoma can be detected and treated before it spreads outside the globe. Retinoblastoma cells can spread to other parts of the body as well. They sometimes grow along the optic nerve to reach the brain. The cells can also grow through the covering layers of the globe into the eye socket, eyelids, and nearby tissues. Once tissues outside the globe are affected, the cancer can spread to the lymph nodes (small bean-shaped collections of immune system cells), to the internal organs and the bones
How is it Treated?
The aim of treatment in retinoblastoma, in order of priority, is to save the life, eye, sight and appearance of the child.
There are many treatment modalities for this tumor and they include:
- Enucleation: This means removal of the eye. The eye with the tumor is removed and is sent for a pathology report. The space is replaced by an artificial implant made of plastic, rubber or coral. The child is fitted with prosthesis or artificial eye, made to match the other eye. This artificial eye, of course, does not have any vision.
- External beam radiation: as an alternative to enucleation, this method of giving radiation treatment to the eye may treat the tumor while preserving the eye. As the tumor is very radiosensitive, this treatment method is very effective. Though the radiation may cause damage to the surrounding structures of the eye, e.g., lens (cataract), lacrimal system (dry eye), orbit (bone maldevelopment) etc. It also increases the chance of developing secondary tumor of the bone, especially in children with tumor involving both eyes.
- Localized Plaque radiation therapy: This method involves applying radioactive plaque close to the tumor on the sclera, and thus gives the radiation therapy in a localized area. It significantly decreases the local complications associated with radiation therapy.
- Photocoagulation: Laser treatment for the tumor is effective and safe for tumors that are smaller in size. In the right cases, this treatment may help in preserving eye as well as the sight of the child.
- Cryotherapy: this involves freezing of the tumor by applying a special probe on the external surface of the eye (sclera). This treatment is done under direct observation and is effective in saving the eye and sight in patients with small tumor.
- Chemotherapy: Treatment with anticancer drugs. There has been a recent preference towards treatment with systemic drugs as an additional treatment. The chemotherapy may decrease the size of the tumor and thus make it more amenable to local treatment like laser, cryotherapy and plaque radiation.
For More Frequently Asked Questions About Retinoblastoma:
http://www.visitech.org/retinoblastoma.html
|
| |