Retinoblastoma Sentence Examples
The department is also a supra-regional center for ocular oncology principally for retinoblastoma affecting children and ocular melanoma in adults.
Different hospitals may recommend different ways to treat retinoblastoma.
Mike's " Life with retinoblastoma " By a parent with a young child who has retinoblastoma.
Top of page trilateral retinoblastoma Occasionally, a new tumor can develop in the center of the brain.
Impairment of vision The majority of children with unilateral retinoblastoma have the affected eye removed.Advertisement
Based on small numbers, families with reduced likelihood of hereditary retinoblastoma reported more positive outcomes.
However, up to 15% of cases of sporadic unilateral retinoblastoma may be hereditary.
Studies of adults were only included where childhood retinoblastoma was followed up into adulthood.
When there is no previous family history of retinoblastoma, the disease is called sporadic.
Children with hereditary forms usually have multifocal, bilateral retinoblastoma, whereas children with the somatic form have unilateral, unifocal disease.Advertisement
Mike 's " Life with Retinoblastoma " By a parent with a young child who has retinoblastoma.
In no case was orbital or metastatic retinoblastoma detected at follow-up.
Sample groups Studies of participants diagnosed with retinoblastoma at the age of 18 years or under were eligible for inclusion.
Top of page Trilateral retinoblastoma Occasionally, a new tumor can develop in the center of the brain.
A child ends up having two copies of each gene, including the retinoblastoma gene.Advertisement
A very important controlling player in this process is the retinoblastoma protein.
The survival rate of our series (91 %) was not different from that usually seen in retinoblastoma patients.
Retinoblastoma tumors can be successfully treated if detected early enough, but the required chemotherapy and surgery can result in blindness.
With regard to the molecular background, no mutation of the p53 or retinoblastoma susceptibility (Rb) genes has been demonstrated.
Immunohistochemical analysis of retinoblastoma protein expression revealed low levels of expression, but no histopathological signs of malignancy.Advertisement
This study could eventually help block the molecular signals that trigger retinoblastoma in children.
Eye cancer (retinoblastoma), a type of colon cancer, and early-onset breast cancer have been shown to be linked to the inheritance of specific genes.
Retinoblastoma is a malignant tumor of the retina that occurs predominantly in young children.
Occasionally a tumor, called a retinoblastoma, develops in the retina of the eye.
When retinoblastoma occurs independently in both eyes, it is then called bilateral retinoblastoma.Advertisement
Occasionally, children with retinoblastoma develop trilateral retinoblastoma, which results from the development of an independent brain tumor that forms in a part of the brain called the pineal gland.
In order for retinoblastoma to be classified as trilateral retinoblastoma, the tumor must have developed independently and not as the result of the spread of the retinal cancer.
The prognosis for trilateral retinoblastoma is quite poor.
The retinal tumor which characterizes retinoblastoma is malignant, meaning that it can metastasize (spread) to other parts of the eye and eventually other parts of the body.
In most cases, however, retinoblastoma is diagnosed before it spreads past the eye to other parts of the body (intraocular) and the prognosis is quite good.
Retinoblastoma can be inherited or can arise spontaneously.
Approximately 40 percent of people with retinoblastoma have an inherited form of the condition and approximately 60 percent have a sporadic (not inherited) form.
Individuals with multiple independent tumors, bilateral retinoblastoma, or trilateral retinoblastoma are more likely to be affected with the inherited form of retinoblastoma.
Approximately one in 15,000 to one in 30,000 infants are born with retinoblastoma, making it the most common childhood eye cancer.
Retinoblastoma is found mainly in children under the age of five but can occasionally be seen in older children and adults.
Retinoblastoma is found in individuals of all ethnic backgrounds and is found equally frequently in males and females.
Retinoblastoma is caused by changes in or absence of a gene called RB1.
A malignant tumor of the retina (retinoblastoma) can result when just one retinal cell loses control of it cell cycle and replicates out of control.
If both RB1 genes in a retinal cell become non-functional, then a retinal cell can become cancerous and retinoblastoma can result.
Approximately 40 percent of people with retinoblastoma have inherited a non-functional or deleted RB1 gene from either their mother or father.
Approximately 90 percent of people who inherit a changed or missing RB1 gene develop retinoblastoma.
People with an inherited form of retinoblastoma are more likely to have a tumor in both eyes (bilateral) and are more likely to have more than one independent tumor (multifocal) in one or both eyes.
The average age of onset for the inherited form of retinoblastoma is one year, which is earlier than the sporadic form of retinoblastoma.
Although most people with the inherited form of retinoblastoma develop bilateral tumors, approximately 15 percent of people with a tumor in only one eye (unilateral) are affected with an inherited form of retinoblastoma.
The chance that the children will inherit the changed/deleted gene and actually develop retinoblastoma is approximately 45 percent.
Some people with retinoblastoma have inherited a non-functioning or missing RB1 gene from either their mother or father even though their parents have never developed retinoblastoma.
It is possible that one parent has a changed or missing RB1 gene in every somatic cell but has not developed retinoblastoma because his or her remaining RB1 gene has remained functional.
Retinoblastoma can also result when both RB1 genes become spontaneously changed or deleted in a retinal cell but the RB1 genes are normal in all the other cells of the body.
Approximately 60 percent of people with retinoblastoma have this type of disease, called sporadic retinoblastoma.
A person with sporadic retinoblastoma does not have a higher chance of having children with the disease.
His or her relatives do not have a higher risk of developing retinoblastoma or having children who develop retinoblastoma.
Sporadic retinoblastoma is usually unifocal and has an average age of onset of approximately two years.
The most common symptom of retinoblastoma is leukocoria.
Children with retinoblastoma can also have problems seeing and this can cause them to appear cross-eyed (strabismus).
People with retinoblastoma may also experience red, painful, and irritated eyes, inflamed tissue around the eye, enlarged pupils, and possibly different-colored eyes.
Children who have symptoms of retinoblastoma are usually first evaluated by their pediatrician.
If the pediatrician suspects retinoblastoma on the basis of these evaluations, he or she will most likely refer the patient to an ophthalmologist (eye doctor) who has experience with retinoblastoma.
It can also sometimes help guide treatment choices, since patients with an inherited form of retinoblastoma may be at increased risk for developing recurrent tumors or other types of cancers, particularly when treated with radiation.
It is helpful for the families of a child diagnosed with retinoblastoma to meet with a genetic specialist such as a genetic counselor and/or geneticist.
These specialists can help to ascertain the chances that the retinoblastoma is inherited and facilitate genetic testing if desired.
If a patient with unilateral or bilateral retinoblastoma has a relative or relatives with retinoblastoma, it can be assumed that they have an inherited form of retinoblastoma.
Even when there is no family history, most cases of bilateral and trilateral retinoblastoma are inherited, as are most cases of unilateral, multifocal retinoblastoma.
However, only 15 percent of unilateral, unifocal retinoblastoma cases are inherited.
The only way to establish whether someone has an inherited form of retinoblastoma is to see if the retinoblastoma gene is changed or deleted in the blood cells obtained from a blood sample.
Approximately 5 to 8 percent of individuals with retinoblastoma possess a chromosomal abnormality involving the RB1 gene that can be detected by looking at their chromosomes under the microscope.
If one of the parents possesses a chromosomal abnormality, then they are at higher risk for having other offspring with retinoblastoma.
Usually, however, a chromosomal abnormality is not detected in a child with retinoblastoma.
In these cases, DNA testing of the blood cells will not be able to ascertain whether someone is affected with an inherited or non-inherited form of retinoblastoma.
If the RB1 gene change/deletion is identified in one of the parents, it can be assumed that the retinoblastoma was inherited and that siblings have a 50 percent chance of inheriting the altered gene.
More distant blood relatives of the parent with the identified RB1 gene change/deletion may also be at risk for developing retinoblastoma.
In this case, there is a 90 to 94 percent chance that the retinoblastoma was not inherited.
In some cases, a person with retinoblastoma will have an RB1 gene change/deletion detected in some of their blood cells and not others.
It can be assumed that this person did not inherit the retinoblastoma from either parent.
Siblings and other relatives would, therefore, not be at increased risk for developing retinoblastoma.
In families where there are multiple family members affected with retinoblastoma, blood samples from multiple family members are often analyzed and compared through DNA testing.
A number of different classification (staging) systems are used to establish the severity of retinoblastoma and aid in choosing an appropriate treatment plan.
An intraocular retinoblastoma may only involve the retina or could involve other parts of the eye.
An extraocular retinoblastoma could involve only the tissues around the eye or could result from the spread of cancer to the brain or other parts of the body.
It is also important to check for trilateral retinoblastoma.
People with an inherited form of retinoblastoma have an increased risk of developing other cancers as a result of this therapy.
Some consideration should, therefore, be given to alternative treatment therapies for those with an inherited form of retinoblastoma.
Often, by the time that unilateral retinoblastoma is diagnosed, the tumor is so large that useful vision cannot be preserved.
Other therapies are unnecessary if enucleation is used to treat intraocular unilateral retinoblastoma.
As of 2004 there are no alternative or complementary therapies specific to the treatment of retinoblastoma.
Since most people diagnosed with retinoblastoma are small children, most drug-based alternative therapies designed to treat general cancer would not be recommended.
Individuals with intraocular retinoblastoma who do not have trilateral retinoblastoma usually have a good survival rate with a 90 percent chance of disease-free survival for five years.
Those with extraocular retinoblastoma have less than a 10 percent chance of disease-free survival for the same amount of time.
Trilateral retinoblastoma generally has a very poor prognosis.
Patients with trilateral retinoblastoma who receive treatment have an average survival rate of approximately eight months, while those who remain untreated have an average survival rate of approximately one month.
Patients with trilateral retinoblastoma who are asymptomatic at the time of diagnosis may have a better prognosis then those who experience symptoms.
Patients with an inherited form of unilateral retinoblastoma have a 70 percent chance of developing retinoblastoma in the other eye.
Retinoblastoma reoccurs in the other eye in approximately 5 percent of people with a non-inherited form of retinoblastoma, so it is advisable for even these patients to be closely monitored.
People with an inherited form of retinoblastoma who have not undergone radiation treatment have approximately a 26 percent chance of developing cancer in another part of the body within 50 years of the initial diagnosis.
Although retinoblastoma cannot be prevented, appropriate screening and surveillance should be applied to all at-risk individuals to ensure that the tumor(s) are diagnosed at an early stage.
For example, a patient with bilateral retinoblastoma has this retinal tumor in both eyes.
Children who have been diagnosed with retinoblastoma should receive periodic dilated retinal examinations until the age of five.
It may be advisable for patients with bilateral retinoblastoma or an inherited form of retinoblastoma to undergo periodic screening for the brain tumors found in trilateral retinoblastoma.
When a child is diagnosed with retinoblastoma, it is recommended that parents and siblings receive a dilated retinal examination by an ophthalmologist who is experienced in the diagnosis and treatment of the disease.
The retinal examinations can be avoided if DNA testing indicates that the patient has a non-inherited form of retinoblastoma or if the sibling has not inherited the RB1 gene change/deletion.
The children of someone diagnosed with retinoblastoma should also undergo periodic retinal examinations under anesthetic.
Top of page Can genetic tests be used to know whether a child will develop retinoblastoma?