Table of Contents
Introduction
Retinoblastoma is a type of cancer that affects the eye and initiates in the retina, which is the lining present within the eye. It is a sensitive part of the inner eye. This type of cancer affects kids more commonly but is rarely known to occur in adults. The retina's function is to sense or detect light and send signals to the brain, which are interpreted into images. It can affect single or both eyes.
What Are the Different Stages of Retinoblastoma?
The most commonly used classification system for retinoblastoma stages is the International Classification of Retinoblastoma (ICRB) system, which includes the following stages:
Intraocular Retinoblastoma:
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Stage A: Localization of some small ones, usually no bigger than 3 millimeters and not in the fovea/macula.
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Stage B: 1 or more large tumors within the retina, equal to or bigger than 3 mm at the sides or in the Macula or the fovea.
Extraocular Retinoblastoma:
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Stage C: Invasion of the tumor through the eyes into the choroid, optic nerve, or anterior chamber.
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Stage D: In such cases, the tumor invasion is beyond the eye, as into the orbit, central nervous system (CNS), or multiple organs.
Treatment of the stages of retinoblastoma comprises a variety of management and treatment approaches, ranging from localized laser therapy and cryotherapy for intraocular tumors to systemic and widespread chemotherapy and radiotherapy for advanced cases.
What Are The Symptoms?
The symptoms are rarely noted, as they commonly affect infants or children.
The following symptoms can be experienced by the patient, or a child may complain of:
1. Redness in the eyes.
2. Swelling in the eyes.
3. Squint eyes or eyes looking in varied directions.
4. The presence of a white halo or color in the pupil when light is projected over the eyes.
If there is a family history of retinoblastoma, one should consult a pediatrician about regular checkups and further examinations.
How Does Retinoblastoma Grow and Spread?
Usually, retinoblastoma does not spread out from the retina; instead, it starts to grow within the retina first. On the other hand, if neglected, it tends to grow and set on the way to other parts of the human body. The spread of retinoblastoma can occur through several mechanisms. The spread of retinoblastoma can occur through several mechanisms:
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Direct Invasion: Therefore, retinoblastoma cells might spread not only nearby within the eye but also throughout the optic nerve, vitreous humor, and other parts of the eye.
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Extension Outside the Eye: The cancer cell may be able to spread deeper into the eye socket (orbit) and around the eye surface.
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Metastasis: Retinoblastoma cells can advance to different body parts in some situations using the bloodstream or the lymphatic system as a foundation. For instance, the brain, bones, bone marrow, or lungs are affected. However, metastasis is less than it is in retinoblastoma compared to other conditions.
The extension of retinoblastoma to other tissues will intensify the symptoms and complications, making treatment difficult. As timely detection and management are important determinants of the fate of the pandemic, efforts should be made to seek early interventions.
How Is It Caused?
1. Genetic:
One of the main causes is a genetic mutation in the nerves of the retina, which leads to abnormal cell growth. Later, these cells spread to nearby structures and may even metastasize to the brain and spinal cord. The cause of the genetic mutation is still not known.
2. Inheritance:
Genetic mutations can occur due to inheritance from parents. It has an autosomal dominant pattern. Not all children with a family history need to develop this or vice-versa. The inherited form shows symptoms in the early stages and may affect both eyes.
Are There Any Complications?
1. Recurrence of Cancer:
Cancer can again affect or recur in the eyes even after treatment. Hence, regular checkups are necessary.
2. Development of Other Forms of Cancer:
Children suffering from retinoblastoma may develop other forms of cancer after their treatment for retinoblastoma, which makes regular checkups necessary.
How Can It Be Prevented?
Since the exact cause is not known, there are no proven ways of preventing cancer. But the following can assist in diagnosing it in the early stages:
Genetic testing can be done to diagnose the condition or the risk of developing it in the early stages, and thus, the prognosis can be improved. If genetic testing detects the possibility of cancer in your child or if there is a family history, your physician will refer you to a genetic counselor.
The genetic counselor will help you understand the importance of genetic testing, its risks and benefits, and the results.
How Can It Be Diagnosed?
When you visit your physician, you or the child will be asked about the signs, symptoms, and family history.
The following tests can be performed to diagnose it:
1. Eye examination. This will be done to examine the changes in the eye.
2. Imaging tests. Certain tests, such as ultrasound, MRI, CT scans, etc., can be performed to check for the extent of cancer.
3. Referral to other doctors. A genetic counselor, oncologist, or surgeon may be part of the team to diagnose and decide on treatment.
How Can It Be Treated?
The treatment depends on the tumor's size, extent, and location. The metastases, the child’s general health, etc., will also be considered in the treatment plan. The main goal is to treat cancer and preserve the child's vision.
The following treatment modalities are available:
1) Chemotherapy:
In this, medications are used to kill cancer cells. It can be given via oral route as pills or via injections. In children, this type of treatment will help shrink the tumor, following which radiation therapy or cryotherapy, etc., can be done.
Intra-arterial chemotherapy is a type of chemotherapy that has recently entered the medical field. In this, the medicine is directly given to the eyes using a catheter, a tiny tube, via the artery of the eye.
2) Radiation Therapy:
Radiation therapy also has the same purpose as chemotherapy, but in some cases, it can cure cancer, if it is small. It can be either Internal radiation (brachytherapy) or external beam radiation. Internal radiation uses a device placed within the cancer area; in external radiation, the X-ray beams are provided from outside.
3) Laser Therapy (Laser Photocoagulation):
In this treatment, the blood vessels supplying oxygen to the cancerous cells are destroyed using a laser. This will kill the cancerous cells.
4) Cold Treatments (Cryotherapy):
In cryotherapy, a highly cold temperature destroys the cancerous cells. Liquid nitrogen or other cold substances are kept near the cancer cells. This freezes the cells, which are later on removed.
5) Surgery:
Surgery is preferred for patients with large tumors. Sometimes, even the eye can be removed to prevent the spread of the tumor to other structures.
The following surgeries can be done:
Enucleation: The surgery aims to remove the affected eye.
Eye implant placement surgery is done immediately after removing the eyeball. In this, a plastic or silicone ball is placed in the eye socket, and the muscles that control eye movements are joined to the implant. This will help with eye movements but will not restore vision.
Artificial eye placement. After several weeks of surgery, a customized artificial eye is placed over the implant. The artificial eye can be customized depending on your child’s natural or healthy eye.
Certain side effects of surgery, like bleeding or infection, can occur. For example, eye removal can lead to the child's loss of vision.
Conclusion:
Retinoblastoma is a tumor affecting the eye, and early detection and management can prevent complications. Online medical platforms will help to get more details on the same, and even a genetic counselor can help you with your doubts. Hence, consult a specialist online to know more about retinoblastoma.
