Eye is an important organ for anyone, without which the whole world is dark. To survive is difficult. Human eye has seven parts, they are- Sclera, the white of the eye; The Cornea, the bulging surface in front of the eye; Anterior and Posterior Chambers, between the iris and the cornea and the iris and the lens respectively; The Iris/ Pupil, it is hole through which light passes; Lens, it is a transparent body consisting of layers, Vitreous humor, it fills the space between the lens and retina.
Retina: It is the layer at the back of the eyeball, which contains cells sensitive to light. It is here that a visual image is formed.
Retinoblastoma is cancer related to the eye.
Retinoblastoma is a malignant tumour found in children. 60% of the cases involve a problem in one eye- unilateral and is not hereditary, and 40% of cases of retinoblastoma are bilateral. Most of them are hereditary. These patients also have the risk of developing other types of cancer. If Retinoblastoma is diagnosed early, it can be treated; otherwise, it can spread to the different parts of the body. The maximum number of cases of Retinoblastoma is found in India, about 1500 new cases every year. This means that 20% of Retinoblastoma patients are from India.
Causes of Retinoblastoma
1) Retinoblastoma starts when the nerve cells dysfunction, which causes impairment in the vision.
2) The diseased cells grow and form a mass of cells called a tumour.
3) The Retinoblastoma cells invade the nearby structures of the eye and can also spread to the brain and spine.
4) It can also be passed from parents to children; even one parent is enough to pass the risk of retinoblastoma. These children can develop the disease at an early age.
5) This retinoblastoma which the gets affected can happen in both the eyes.
- Children who inherit this disease, there is a risk that the condition can return in and around the treated eye.
- The doctor can always ask for several eye checkups.
- After the treatments complete, the doctor might ask to come for a few months for a few years. This follow-up is a must.
- Even after treatment, these children can develop other types of cancers in any part of the body.
As retinoblastoma is the diseases of infants and small children, symptoms are rarely seen.
visible Symptoms are:
- A white colour in the pupil, when it is flashed in the eye.
- Eyes may appear to look in different directions.
- Redness and swelling in the eye.
Firstly, there is no evidence to prevent retinoblastoma.
If there is a family history of retinoblastoma, prevention is not possible.
If eye checkups are done at an early age, whose parents have this disease, then that particular child can be identified who might be affected with it.
If diagnosed early when the tumour is small, the cure is possible and vision can be safeguarded.
These early diagnoses can also help to find out if other related cancers are developing.
Radiation therapy, Chemotherapy, Thermotherapy and Brachytherapy, with Chemotherapy, the tumour is reduced but not cured.
The tumour size is reduced and then treated with Cryotherapy, Laser photocoagulation, thermotherapy, and plaque radiotherapy.
Staging of Retinoblastoma
If it is not treated immediately, there are chances that it might divide to the central nervous system, via optic nerve, bone and bone marrow through the blood and lymph nodes.
Based on the histopathology and imaging findings, treatment is given. This is mainly done at stage III and stage IV levels.
The first aim of the therapy is to save the patient’s life and saving the vision in the affected eye is also essential.
A team of doctors plan the mode of treatment—the OPHTHALMOLOGIST, PEDIATRIC ONCOLOGIST and PEDIATRIC RADIATION ONCOLOGIST.
There are three possible treatments: SURGERY, CHEMOTHERAPY, RADIOTHERAPY.
If chemo and conservative treatment have failed, a surgery(enucleation) is treated.
Earlier EXENTERATION treatment used to be done, but as this surgery disfigures the face, mostly it is not done.
Next is FOCAL CONSOLIDATIVE MEASURES like
a) LASER PHOTOCOAGULATION—Tumors which are not more than 2mm this treatment is given.
b) THERMOTHERAPY: In this method, the tumor is heated to a temperature of 42-60 degrees, for cancer not more than 3mm in size.
c) CRYOTHERAPY: Tumors that are not more than 3mm in diameter and 1.5mm in thickness are treated using this surgery.
d) CHEMOTHEMOTHERAPY: Tumors with a diameter of 15mm or more are treated with a combination of TRANSPUPILLARY, THERMOTHERAPY AND CHEMOTHERAPY.
Retinoblastoma is treated through different drugs. There are FOUR possible ways.
- CHEMOREDUCTION: This treatment reduces the volume and is less-damaging treatment. It takes six cycles of chemotherapy.
- PERIOCULAR CHEMOTHERAPY:- For effective treatment, higher dosage is given and also to reduce the side effects.
The other chemotherapies are
- INTRATERIAL CHEMOTHERAPY
- CHEMOTHERAPIES for locally advanced disease; high-dose and stem-cell transplant and so on.
Retinoblastoma is a susceptible tumour, so radiotherapy is used at different stages:-
- PLAQUE THERAPY ( BRACHYTHERAPY ): This for the tumours sized 15mm in diameter and 7-8 mm thick.
- EXTERNAL BEAM RADIOTHERAPY:-EBRT treatment is for multiple giant tumours.
- EBRT IN EXTRAOCULAR RETINOBLASTOMA and other radiotherapies are given.
There are a number of challenges to treat Retinoblastoma in India, as the diagnoses are delayed, presentation delay, compliance to treatment is poor, frequent hospital visits, longer duration of treatment, involvement of multiple specialities and the cost.
FREQUENTLY ASKED QUESTIONS about RETINOBLASTOMA:
1) CAN RETINOBLASTOMA BE CURED?
ANS) If the tumor—in one or both the eyes- 95% of the patients can be cured.
70 to 80 % of the children who are affected with retinoblastoma can be cured.
- If a patient is treated very late, then loss of the eye and if the tumour spreads to the brain, then that leads to death.
2) CAN RETINOBLASTOMA RETURN?
ANS) Mostly it does not come back, but children who were treated for them later in life
It can come back. In case it comes back, treatment depends on the site, if it is small and the eye chemotherapy, laser, radiation and enucleation surgery is needed. If cancer comes about outside the eye, then the treatment depends on many factors.
3) CAN RETINOBALSTOMA BE PREVENTED?
ANS) Cancers can be prevented by avoiding smoking or taking proper care at the workplace if working with chemicals, but there are no risk factors for not getting retinoblastoma.
- If the parent has this disease before childbirth, genetic counselling is needed after immediate childbirth detection improves the chance for successful treatment.
4) CAN RETINOBLASTOMA BE IN BOTH THE EYES?
ANS) If RETINOBLASTOMA affects one eye, it is usually diagnosed within one year; otherwise, it is diagnosed later in life( between 2 or 3 years.)
Awareness or The Disease Retinoblastoma
Though people are aware of this disease, most of the do not think that it is a life-threatening disease. Most of the medical students and Pediatricians lack enough knowledge of this disease. So it is necessary to update them continuously about this disease by conducting medical education programs.