Non-hereditary Retinoblastoma

Non-hereditary retinoblastoma is a rare form of cancer that usually affects children under the age of six. This type of retinoblastoma is typically unilateral, meaning that it only affects only one eye. Non-hereditary retinoblastoma rarely spreads beyond the original site and usually does not involve recurring tumors. About 60 percent of retinoblastoma cases are non-hereditary, also called sporadic, retinoblastoma.

Diagnosis of Non-hereditary Retinoblastoma

Since there is no family history of retinoblastoma in cases of sporadic retinoblastoma, diagnoses are often made later than cases of hereditary retinoblastoma. The average age for diagnosis of non-hereditary retinoblastoma is eighteen months for children that were born with the disease. However, non-hereditary retinoblastoma sometimes develops months or years after birth, which also affects the average age of diagnosis.

Non-hereditary Retinoblastoma Detection

Like all types of retinoblastoma, the easiest way to detect the abnormality in the eye is by a whitish spot in the pupil when the eye is exposed to direct light. This is often visible in pictures, because of the flash. If this spot, called leukocoria, is detected, parents should request to have the child seen by specialists and tested for retinoblastoma. Since biopsies pose a threat to vision, scan tests such as MRIs and ultrasounds are typically used to look for tumors behind the eyes.

Other symptoms that may indicate non-hereditary retinoblastoma include:

  • One eye drifting towards center or “floating”
  • Decreased vision
  • Inflammation
  • Glaucoma
  • Pain in eye
  • Redness in eye

Non-hereditary Retinoblastoma Cause

An abnormality in a gene that occurs during development begins the chain of events which results in non-hereditary retinoblastoma. Each cell typically has two retinoblastoma genes. In a patient that has non-hereditary retinoblastoma, both of the retinoblastoma genes are missing from one cell in the retina.

Since these genes are responsible for regulating cell production, the cell is able to reproduce at an irregular pace. The cells that are produced during this genetic malfunction form the retinoblastoma tumor. While the flawed cell may be present at birth, the tumor may not have been formed or may be too small to detect during the baby’s first check-ups.

Curing Non-hereditary Retinoblastoma

Pediatric Retinoblastoma is a highly curable disease, and about 90 percent of all children diagnosed survive. Since most patients that are diagnosed with non-hereditary retinoblastoma have only one tumor in one eye, the patient is considered cured when the single tumor is eliminated. Patients that have been treated for non-hereditary retinoblastoma have only a slightly higher risk of developing tumors in other areas of the body than patients that have undergone no cancer treatment, so subsequent cancer screenings typically stop much sooner than patients that have been diagnosed with hereditary retinoblastoma.

Sources:

Boughton, Barbara. “Retinoblastoma, Part Two: Secondary Neoplasms in Older Children.” Eyenet Magazine. American Academy of Ophthalmology, n.d. Web. 27 Nov 2013. <http://www.aao.org/publications/eyenet/201004/oncology.cfm>.

Draper, GJ, BM Sanders, and et al. “Patterns of Risk of Hereditary Retinoblastoma and Applications to Genetic Counselling.” PubMed.gov. U.S. National Library of Medicine, n.d. Web. 27 Nov 2013. <http://www.ncbi.nlm.nih.gov/pubmed/1637670>.

“What is Retinoblastoma.” American Cancer Society. American Cancer Society, 06 Aug 2012. Web. 27 Nov 2013. <http://www.cancer.org/cancer/retinoblastoma/detailedguide/retinoblastoma-key-statistics>.