Retinoblastoma is a malignant eye tumor that develops from cells of immature retina. Retina is inner light-sensitive layer of eye on which light is focused and further transformed into a nerve signal that is transmitted along visual pathways to cerebral cortex.
Retinoblastoma is a rare tumor that develops primarily in young children (most often diagnosed in children under 2 years of age). It occurs with a frequency of 1 case per 15-30 thousand children and accounts for only 2% of all malignant diseases of childhood. The disease occurs sporadically, but may also have a hereditary predisposition. Retinoblastoma can be unilateral (75% of cases) or bilateral (25% of cases). If a child is diagnosed with damage to both eyes, then most likely the disease is genetic.
Important! If retinoblastoma is detected early, the disease has a favorable prognosis. Treatment effectiveness rate in this case is 95%. If specific therapy is not prescribed on time, prognosis worsens and tumor spreads to neighboring tissues.
If your child has been diagnosed with retinoblastoma or there is a suspicion of such a diagnosis, do not hesitate! Contact specialists who have experience in managing patients with retinoblastoma according to modern treatment protocols. A competent doctor who uses innovative treatment methods will help not only save child’s life, but also his vision.
These are specialists who work in Pediatric Oncology Department of multidisciplinary medical center Tel Aviv Medical Clinic.
All our doctors are highly qualified and have extensive practical experience in treating young patients with retinoblastoma. Most of them repeatedly completed internships at the best oncology hospitals in USA and Europe, where they additionally acquired professional communication skills with children with cancer. An individual approach to each case of retinoblastoma in a child is an undeniable advantage of treatment at TAMC. Developing an examination and treatment plan, specialist does not use one template for everyone, but develops a personalized scheme that takes into account child’s characteristics and certain nuances of his disease. This makes it possible to create the most effective personalized treatment regimen for each small patient, which in future only has a positive effect on long-term prognosis.
A positive point for patient and his relatives is a multidisciplinary approach to each case. That is, assistance to one child with retinoblastoma is provided simultaneously by a whole team of specialists – oncologists, ophthalmologists, surgeons, neurosurgeons, radiation therapists, radiologists, chemotherapists, psychologists, rehabilitation specialists and other highly specialized specialists if necessary.
Causes of retinoblastoma in children
There are 2 types of retinoblastoma, depending on reasons for its development: sporadic (non-hereditary) and hereditary.
In 75% of cases, doctors deal with sporadic retinoblastoma, in which mutation that leads to tumor progress develops spontaneously (for no apparent reason) in one single cell of retina. Due to its uncontrolled growth and reproduction, a whole tumor grows. A mutation specific for retinoblastoma develops in the RB1 gene. Most patients with sporadic retinoblastoma are diagnosed with unilateral lesions.
In approximately 25% of cases, hereditary retinoblastoma is diagnosed, in which a mutation in the RB1 gene is inherited and is present in every cell of the body. Mutation may occur for the first time in this family, and in this case, a child with retinoblastoma will be the first in this family with this disease, the probability of transmitting the disease gene to subsequent generations is 50%. Most patients with genetic retinoblastoma have two eyes affected (bilateral tumor location).
Symptoms of retinoblastoma in children
The pediatrician may suspect retinoblastoma at the next scheduled visit, but, as a rule, parents themselves notice that not everything is in order with child’s eye.
The main symptoms of retinoblastoma:
- Leukocoria (“cat’s eye effect”). Normally, ocular fundus reflex is red, so in photo (especially with a flash) our eyes glow red. A child with retinoblastoma has a white reflex from the bottom of eyeball. This is very noticeable in photo of the child and catches parents eye.
- Symptom of “lazy eye”. Displacement of eyeball to the side when child looks straight ahead.
- Changes iris color in a child – heterochromia.
- Eye redness.
- Decreased visual acuity, loss of visual fields, and other disorders.
- Increased intraocular pressure and pain in affected eye.
- As the tumor spreads, general symptoms of cancer may appear – nausea, vomiting, headache, exhaustion, weakness, etc.
As a rule, retinoblastoma is diagnosed in the early stages due to a very specific symptom – leukocoria. Very rarely, the disease is diagnosed in late stages with a widespread oncological process.
Modern diagnostic methods
If your child shows signs of retinoblastoma, it is important to visit a pediatric ophthalmologist. A specialist can conduct an outpatient screening examination and determine the need for further diagnostics. If retinoblastoma is suspected, the child is referred for consultation to an ophthalmologist who specializes in childhood eye cancer.
Retinoblastoma diagnostics is made by a thorough examination of eye under anesthesia. During the procedure, doctor examines eyeball using a special microscope under dilated pupil conditions. This procedure is performed under general anesthesia in young children and local anesthesia in older children so that the doctor can examine the entire retina in detail.
An ophthalmological examination of a child with suspected retinoblastoma includes:
- Ophthalmoscopy with a dilated pupil is an examination of all eye and fundus structures using a modern ophthalmoscope, which allows us to obtain an image with several times magnification.
- Recording changes in fundus using special drawings. This allows the doctor to monitor dynamics, disease progression or monitor treatment effectiveness in future.
- Photographic recording of changes in fundus using a special RetСam camera. These photographs, together with ophthalmologist’s drawings, serve as a starting point for tracking the dynamics of changes in future.
- Eye ultrasound is a simple and accessible, non-invasive method for diagnosing eye tumors, including retinoblastoma. Allows us to assess the location, size and thickness of tumor.
- Measuring intraocular pressure.
- Electroretinography, which allows you to evaluate the electrical activity of retina and identify violations of its function.
As a result of such a high-quality and quick (takes up to 30 minutes) ophthalmological examination, a primary diagnosis can be formed and a further plan of additional examinations can be developed to confirm the diagnosis of retinoblastoma.
With retinoblastoma, collecting a family history is of great importance, which allows us to determine whether the disease is hereditary or sporadic.
Visual diagnostic methods (eye ultrasound, MRI, CT, OCT) to confirm the diagnosis, determine the size and extent of tumor spread are used in each case of the disease.
A biopsy is not used to diagnose retinoblastoma because this invasive procedure may cause the cancer cells to spread, and preliminary tests are sufficient to confirm the diagnosis of retinoblastoma.
Children, parent or sibling with a history of retinoblastoma should be examined by an ophthalmologist soon after birth and then every 4 months until 4 years of age. Patients with retinoblastoma should undergo molecular genetic testing to determine if they are carriers of retinoblastoma gene (RB1).
Prognosis for retinoblastoma
Most children diagnosed with cancer such as retinoblastoma can make a full recovery and retain their vision. Since pathology is detected early and prognosis mainly depends on retinoblastoma stage, the prognosis is favorable. The 5-year survival rate for children with retinoblastoma that does not extend beyond the eye is more than 95%.
Modern treatment of retinoblastoma
The treatment plan for retinoblastoma depends on whether one or both eyes are affected, as well as disease stage and tumor extent. For specific treatment of this cancer, surgery, focal therapy, chemotherapy, and radiation are used.
As a rule, doctors at Pediatric Oncology Department of TAMC use combined treatment. Before starting therapy, it is imperative that treatment plan is discussed with patient and his family members to determine all the risks and benefits, both short-term and long-term.
Chemotherapy is often used in modern treatment protocols for retinoblastoma, especially in children under 3 years of age. As a rule, a course consists of a combination of two or more drugs at the same time. Chemotherapy can be systemic, where drugs are administered orally or intravenously and distributed evenly throughout the body, or it can be regional. With regional chemotherapy, drugs can be injected into the area around eyes (periocular chemotherapy), or they can be injected directly into eyeball (into vitreous body – intravitreal chemotherapy).
In modern oncology centers, including TAMC, patients with retinoblastoma undergo an innovative procedure – chemosurgery of ophthalmic artery (intra-arterial chemotherapy). In this case, chemotherapy drugs are delivered directly to ophthalmic artery. Thanks to this precision, it is possible to create the maximum concentration of necessary drugs directly around the tumor, while remaining healthy tissues are subject to minimal toxic effects.
Focal therapy is a minimally invasive surgical technique that acts directly ontumor. Often, a combination of chemotherapy and one type of focal therapy is sufficient to completely cure the patient. At TAMC, patients have the opportunity to undergo treatment using the following focal therapy techniques: laser therapy, cryotherapy, brachytherapy.
Laser therapy is a method of destroying cancer cells using high-intensity light (laser photocoagulation) or heat (transpupillary thermotherapy).
Cryotherapy – this procedure uses short-term ultra-low temperatures to reduce tumor size and kill cancer cells.
Brachytherapy is a small device made of radioactive material that is placed on the surface of eye directly above tumor site. After a short time, usually 3-4 days, the radioactive plaques are removed.
If necessary, ophthalmologists can perform surgical eye removal. Surgery to remove the eye is called enucleation. TAMC surgeons extremely rarely resort to such treatment; basically, all treatment procedures for retinoblastoma are minimally invasive and organ-preserving.
In some cases, radiation therapy is used to treat retinoblastoma. Radiation therapy can destroy cancer cells or stop their growth. External beam radiation therapy uses a machine (linear accelerator) located outside the body that irradiates the entire eye (external beam radiation). This is the most aggressive treatment for retinoblastoma and can be used to preserve vision and prevent the disease from spreading. Because of potential for long-term effects and risk of secondary cancer, radiation is typically reserved for patients whose disease has spread outside the eye, who have not responded to other treatments, or who have relapsed.
Very rarely, retinoblastoma spreads to brain, bones, or bone marrow. In this case, high-dose chemotherapy followed by autologous bone marrow transplantation may be required.
During the entire treatment and for some time after it, children undergo regular examinations. When diagnosed early, relapses respond well to focal therapy. The frequency and duration of follow-up is determined by the attending physician.
