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Diagnosis and treatmentSigns and SymptomsThere are two common signs of retinoblastoma: firstly, an abnormal appearance of the pupil, which tends to reflect light as a white reflex, like a cat's eye, and secondly, a squint.  Less commonly, parents may notice a deterioration in their child's vision, or the eye may become red and inflamed. Pain is an uncommon symptom. Apart from the eye problem, the majority of children are otherwise well. However, a small proportion of children are referred to their local Paediatrician because of faltering growth or delayed development. In these children a chromosome test may reveal an abnormal chromosome 13, with loss of the part of the chromosome containing the RB1 gene. Finding this deletion alerts the Paediatrician to the possibility of retinoblastoma, and can thereby lead to a diagnosis of retinoblastoma at an early stage, before symptoms or signs develop. Not all children with a deletion on chromosome 13 will develop retinoblastoma. If you are concerned about your child and recognise any of the symptoms above you should ask your GP or Optician to do a test for the red reflex. If you want to download our See Red poster which explains how a red reflex examination is done  click hereDiagnosis and investigationThe diagnosis of retinoblastoma is made by an eye specialist known as an Ophthalmologist, or Ophthalmic Surgeon, who is able to recognise the characteristic appearances of the tumour. The Ophthalmologist will examine the back of the child's eyes under a general anaesthetic, using a special instrument known as an ophthalmoscope. S/he will be able to see if there is more than one tumour, and may also see whether the tumour is affecting the main nerve to the eye, called the optic nerve. An ultrasound test of the eye may be done to help confirm the diagnosis and assess the size of the tumour. For eyes with small tumours, photographs will be taken with a special camera so that the Ophthalmologist can monitor the response to treatment. Once the diagnosis has been confirmed, the Ophthalmologist will discuss the child's treatment with a Paediatric Oncologist, who is a specialist in the treatment of children's cancers. Sometimes it is necessary to undertake a special scan of the head and eyes, either a CT or MRI scan, to confirm the diagnosis and to check for any signs of the tumour spreading. TreatmentThe aims of treatment are firstly, to preserve the life of the child, secondly, to preserve vision and thirdly, to minimise any complications or side-effects of treatment. There are a number of different treatment methods available for children with retinoblastoma, and the decision as to which is the most suitable treatment for the child will be made by the Ophthalmologist in discussion with the Paediatric Oncologist , taking into account the size, location and number of tumours within the eye, and the potential for vision. If both eyes are affected, each eye will be treated on its own merit. The Ophthalmologist together with the Paediatric Oncologist will discuss the options for treatment with the parents, and advise on the most suitable treatment for the child. CryotherapySmall tumours, up to approximately 6 mm in size, which are located in the periphery of the retina at the front of the eye, can be treated by a freezing treatment known as cryotherapy. An instrument called a cryoprobe is placed on the outer surface (the sclera) of the eye, at a position overlying the base of the tumour, and the tumour cells are killed by being frozen. This treatment is carried out under a general anaesthetic and may need to be repeated on two or three occasions over a period of several weeks. The eyelids tend to look slightly puffy, and the eye may be a bit sore for a day or two after cryotherapy. The child will need to have eye drops for a few days following this treatment. ChemotherapyChemotherapy, or drug treatment, is used in the first stage of treatment for most patients with bilateral retinoblastoma, and can be used for both small and large tumours. It is also sometimes used for unilateral retinoblastoma, but only in situations where the tumour is relatively small and there is a good chance of preserving useful vision in the affected eye. Chemotherapy may also be used after surgery to remove an eye, but only if the tumour has invaded the tissue outside the eye. Children with a known family history of retinoblastoma are usually diagnosed at a very young age, and are likely to have relatively small, but multiple, tumours. For such children, a combination of cryotherapy for small tumours at the front of the eye, and chemotherapy for more posterior tumours is now used as first line treatment rather than radiotherapy. Chemotherapy may also be used to shrink larger solitary tumours, to make it possible to apply either a radioactive plaque or laser therapy. Usually either four or six courses of chemotherapy will be given. The number of courses will depend on the size of the tumour. When chemotherapy is recommended, the child will be under the care of a Paediatric Oncologist, who specialises in the drug treatment of cancer in children. Chemotherapy is given via a central intravenous line, a tube which is inserted into the main vein that drains into the heart, and this will stay in for the duration of the chemotherapy. The nursing staff on the Paediatric Oncology ward will teach the parents how to look after the central line. Chemotherapy does have a number of short term side-effects, including nausea and vomiting, increased susceptibility to infection, tendency to easy bruising and temporary loss of hair. Fortunately, there are various drugs which can be given to counteract the nausea and vomiting, and young children do not usually mind about the hair loss. Parents can be reassured that their child's hair will grow back quite normally, once the chemotherapy has been completed. In addition, fertility is not known to be impaired by the drugs used in the first line treatment of retinoblastoma. Although the use of chemotherapy is still undergoing evaluation, it is hoped that there will be fewer long-term side-effects following treatment with chemotherapy than with radiotherapy. Radioactive plaquesDepending on the location of the tumour, solitary tumours measuring between 6-12 mm, can be treated by the application of a radioactive scleral plaque, using radioactive iodine or ruthenium. This treatment is suitable when there is only one tumour, which is situated away from the optic nerve and the light sensitive area of the eye called the macula. If the child has treatment with a plaque, s/he will have to be nursed in isolation for a few days, and close contact with other people will be limited. However, it is usually possible for one parent to stay in the room with the child, as long as their bed is an adequate distance from the child. The child will need to be in isolation for between 1-3 days, the exact time depending on the activity of the plaque, and the amount of radiation that is required for the particular tumour being treated. The child will need to have a general anaesthetic so the plaque can be inserted and another one to remove the plaque. Pregnant women and children are not allowed to visit during this period. In some cases, chemotherapy may be given to shrink the tumour, prior to the application of a radioactive plaque. Laser therapySome tumours are suitable for treatment by laser, either alone or in combination with chemotherapy. In the latter group, laser may be given either to enhance the effect of chemotherapy, a treatment known as chemothermotherapy, or to consolidate the effect of primary chemotherapy after the tumour has reduced in size. When given to consolidate the effect of primary chemotherapy, the laser beam is applied around the outer margin of the tumour and acts by cutting off the blood supply to the tumour. When given to enhance the effect of chemotherapy, a diode laser is used and the child receives an infusion of chemotherapy (usually a drug called Carboplatin) on the ward, and is then taken to theatre and, under a general anaesthetic, the diode laser is applied to the surface of the tumour to heat the tumour and thereby increase the uptake of the chemotherapy drug into the tumour. This latter treatment is more commonly used as second line therapy for recurrent tumours, rather than as part of first line treatment. External beam radiotherapyRadiotherapy is also used as second line therapy for tumours which fail to respond well to chemotherapy, and also for recurrent tumours relapsing after primary chemotherapy. External beam radiotherapy is given by a specialist known as a Radiotherapist, or Clinical Oncologist who works in a radiotherapy centre. The treatment will be given on a daily basis over a period of 4 - 5 weeks, giving a total of about 20 treatments. Most radiotherapy centres work from Monday to Friday, so it is usually possible for the child to go home at weekends. The treatment is usually done on a daily out-patient basis and if the family do not live near the radiotherapy centre they are often provided with somewhere to stay locally. The child will be given a general anaesthetic for the radiotherapy as it is essential that s/he remains perfectly still during the treatment. The actual treatment only lasts about 2 or 3 minutes each day, but there is a lot of preparation to make sure that the beam is directed accurately on the tumours in the retina. This involves a planning session, when the set-up is tested to make sure everything is in the right position. In most children, it is possible to protect the lens of the eye during radiotherapy: this is known as lens-sparing radiotherapy. Other children who have more extensive tumours, or vitreous seedlings, may need to have the whole eye irradiated. Unfortunately, this will cause some damage to the lens of the eye so that 18 months to 2 years after treatment, the child may develop a cataract. Although a cataract can be removed by surgery, the eye is likely to be rather sensitive to bright lights after removal of the cataract. Such children may need to wear tinted glasses when they are out in the sunlight. After whole eye radiotherapy, the eye will also be rather dry due to damage to the lachrymal gland, and so it will be necessary for the child to use lubricating eye drops and cream on a regular basis. SurgeryIf the tumour is very large and has damaged the sight in the eye beyond repair, then the Ophthalmologist will recommend that the eye be removed. This operation is called an enucleation. The ophthalmologist looking after the child will always do everything s/he can to preserve vision, and will only recommend enucleation if s/he feels that the other treatments would not be effective, and would put the child's life at risk. The UK Childhood Cancer Study Group state that 85% of children with unilateral retinoblastoma will require an enucleation, whilst the number of children with double enucleations (both eyes removed) has reduced to 5% (reduced historically from 13%). Children recover very rapidly following this surgery. It is not usually a particularly painful operation, and there are no stitches to be removed. Usually the child will be able to come home one or two days after the operation and the nurses on the ward will teach the parents how to put antibiotic drops into the socket. These drops are necessary for about two weeks, until the tissues in the socket have healed over. Before an artificial eye is fitted a conformer is worn. It will be put in during the operation. It is worn to protect the socket whilst it is healing. Conformers can be clear or be coloured like an eye. Ocular ImplantsAt the time of the operation, an implant which is usually made of either hydroxyapatite or acrylic, will be placed into the floor of the socket to help improve the cosmetic appearance of the artificial eye. The implant itself is also covered by a synthetic material or mesh. Occasionally, because the implant is a "foreign body", it is "rejected" by the body and the tissues overlying it break down, in which case further surgery may be necessary to repair the defect. Sometimes, the implant may need to be removed because of recurrent episodes of rejection or infection. An article has been written by Mr Manoj Parulekar a Consultant Paediatric Ophthalmologist and retinoblastoma specialist with the retinoblastoma team at Birmingham Children's Hospital. The article is about Ocular Implants and was written for the Daisy's Eye Cancer Fund. To read the article PathologyWhen an eye has to be removed, it is sent to an experienced pathologist who will examine it carefully under the microscope. The pathologist looks for evidence of retinoblastoma cells in the optic nerve and blood vessels of the eye, and also for extension of tumour cells into the front part of the eye. If s/he finds any features of concern, further treatment with be necessary, either chemotherapy or radiotherapy to the socket will be recommended, to kill off any retinoblastoma cells which may have spread outside the eye. An appointment will be made for the parents to go back to see the Ophthalmologist about two weeks after the child's operation, so that s/he can check the pathology report and advise on whether or not any further treatment is required. When chemotherapy is necessary after enucleation, a number of tests will be done to check that the tumour has not spread outside the eye. The investigations may include blood tests, a lumbar puncture to examine the cerebrospinal fluid (CSF) which surrounds the brain and spinal cord, and a bone marrow test. In some cases, a bone scan and MRI scan of the head may need be done. The Paediatric Oncologist will advise which tests are necessary. If chemotherapy is recommended after an enucleation it is because the pathologist feels that there is a risk that some tumour cells may have escaped outside the eye, either through the blood vessels or along the optic nerve. The doctor may talk about invasion of the "choroid", one of the coats of the eye adjacent to the retina, which contains a lot of blood vessels. If there is extensive invasion of the choroid by tumour, or if retinoblastoma cells can be seen extending into the optic nerve, "adjuvant" chemotherapy will be advised. Usually either four or six courses of chemotherapy will be given and the number of courses will depend on the extent of the tumour invasion. Sometimes, when tumour cells are seen in the optic nerve, it is necessary to give chemotherapy directly into the spinal fluid to help prevent retinoblastoma developing in the meninges, the membranes covering the brain. This will usually be done by means of a lumbar puncture, under a short general anaesthetic. Artificial EyesThe artificial eye, or "prosthesis" as it is sometimes called, will be fitted about six weeks after the operation. At the time of the operation arrangements will be made by the surgeon who removes the eye, for the child to go to an eye fitting specialist at the artificial eye centre nearest to their home. This will help the family avoid having to travel long distances. The child will have to visit the Artificial Eye Specialist or Prosthetist fairly regularly as a new eye will have to be made so that it fits well. The eye socket will continue to grow with the child. To read the section on our website about artificial eyes click here Soon we will have links to different artificial eye services websites from this site. To view the current useful links page visit click here |
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