The stage of cancer describes how far it has spread. The outlook (prognosis) for children with retinoblastoma depends, to some extent, on the cancer’s stage. The stage is also an important factor in choosing treatment.
Retinoblastoma is staged based on the results of eye exams, imaging tests, and any tests that were done, which are described in Tests for Retinoblastoma.
A staging system is a standard way for your child’s cancer care team to sum up how far a cancer has spread. Doctors use staging systems to predict the outlook for saving the child’s vision, as well as for survival and the likelihood that certain treatments will be effective.
When determining the best treatment options, doctors often divide retinoblastomas into 2 main groups:
In the United States, most retinoblastomas are diagnosed before they have spread outside the eye, so staging systems that apply only to intraocular retinoblastoma are used most often in this country. There are 2 staging systems for intraocular retinoblastomas.
It’s important to know that regardless of the stage, almost all children with intraocular retinoblastoma can be cured if they are properly treated. But the stage has a bigger impact on whether the affected eye (or the vision in the eye) can be saved.
The International Classification for Intraocular Retinoblastoma is the staging system that most doctors now use. It divides intraocular retinoblastomas into 5 groups, labeled A through E, based on the extent of the cancer and on the chances that the eye can be saved using current treatment options.
Small tumors (no more than 3 millimeters [mm] across) that are only in the retina and are not near important structures such as the optic disc (where the optic nerve enters the retina) or the foveola (the center of vision).
All other tumors (either larger than 3 mm or close to the optic disc or foveola) that are still only in the retina.
Well-defined tumors with small amounts of spread under the retina (subretinal seeding) or into the jelly-like material that fills the eye (vitreous seeding).
Large or poorly defined tumors with widespread vitreous or subretinal seeding. The retina may have become detached from the back of the eye.
The tumor is very large, extends near the front of the eye, is bleeding or causing glaucoma (high pressure inside the eye), or has other features that mean there is almost no chance the eye can be saved.
The Reese-Ellsworth system was developed in the 1960s, when most children were being treated with external beam radiation therapy (EBRT). While this is no longer a common treatment, some doctors may still use this system to classify retinoblastomas that have not spread beyond the eye. This system can help determine the likelihood of preserving vision while still treating the tumor.
Terms such as favorable, doubtful, and unfavorable used in this staging system refer to the likelihood that the cancer can be treated while saving the affected eye, not to the likelihood of the child’s survival. Indeed, more than 9 in 10 children with intraocular retinoblastomas are cured. The major challenge is saving the vision in the affected eye.
To explain the groupings below, it helps to define a few terms.
The Reese-Ellsworth staging system divides intraocular retinoblastoma into 5 groups. The higher the group number, from 1 to 5, the lower the chance of controlling the retinoblastoma or of saving the eye or any useful vision.
Other staging systems that include both intraocular retinoblastomas and those that have spread beyond the eye (extraocular retinoblastomas) may be used by some doctors. These can be especially useful in countries where these cancers are more likely to have spread by the time they are found. For example, the American Joint Commission on Cancer (AJCC) staging system takes into account 4 key pieces of information:
This system can be used to describe the extent of retinoblastomas in detail, particularly for those that have spread outside the eye, which rarely happens in the United States.
The different staging systems used for retinoblastoma can be confusing. Be sure to ask your child’s doctor if you have any questions about the stage of your child’s cancer.
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
American Joint Committee on Cancer. Retinoblastoma. In: AJCC Cancer Staging Manual. 8th ed. New York, NY: Springer; 2017: 819-831.
Hurwitz RL, Shields CL, Shields JA, et al. Chapter 27: Retinoblastoma. In: Pizzo PA, Poplack DG, eds. Principles and Practice of Pediatric Oncology. 7th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2016.
Kaufman PL, Kim J, Berry JL. Retinoblastoma: Clinical presentation, evaluation, and diagnosis. UpToDate. Accessed at www.uptodate.com/contents/retinoblastoma-clinical-presentation-evaluation-and-diagnosis on September 18, 2018.
National Cancer Institute. Retinoblastoma Treatment (PDQ®). 2018. Accessed at www.cancer.gov/types/retinoblastoma/hp/retinoblastoma-treatment-pdq on September 18, 2018.
Rodriguez-Galindo C, Orbach DB, VanderVeen D. Retinoblastoma. Pediatr Clin North Am. 2015;62(1):201-223.
Last Revised: December 3, 2018