Stages of retinoblastoma

Talk to the doctor if you have questions. Find out more about staging cancer.

The International Intraocular Retinoblastoma Classification (IIRC) is used to predict how likely the eye can be saved with current treatment options.

The tumours are 3 mm or smaller and are only in the retina. The tumours are away from the fovea (a structure within the retina) and optic disc (the area where the optic nerve leaves the back of the eye).

Tumours are larger than 3 mm and in any part of the retina.

There may be some tiny areas of cancer spread within the back of the eye or vitreous humour (called focal seeding), and some of the retina may be detached.

The cancer has spread throughout the back of the eye or vitreous humour (called diffuse seeding), and some or all of the retina may be detached.

There is no longer sight in the eye with cancer and any of the following:

• the tumour is touching the lens or has grown into the front of the eye
• the tumour is causing increased pressure in the eye (called glaucoma)
• the tumour is spread throughout retina (called diffuse infiltrating retinoblastoma)
• there is blood in the front of the eye or bleeding from the eye
• the eye looks infected but isn’t
• the eyeball shrinks and loses function (called phthisis bulbi)

The International Retinoblastoma Staging System (IRSS) is based on how much cancer remains after surgery or whether the cancer has spread.

The tumour is only in the eye. The eye won’t be removed and the tumour will be treated without using surgery.

The tumour is only in the eye. The eye will be removed (called an enucleation) so that no cancer cells remain.

The tumour is only in the eye. The eye will be removed and any cancer cells that remain will only be seen under a microscope.

Cancer has spread from the eye to tissues around the eye socket (orbit).

Cancer has spread from the eye to lymph nodes near the ear or in the neck.

Cancer has spread to 1 or more parts of the body, such as the liver or bone.

Cancer has spread to the brain or spinal cord (called the central nervous system, or CNS). It may have also spread to other parts of the body.

The American Joint Committee on Cancer (AJCC) staging system uses the TNM staging system. The TNM staging system is used to stage many solid tumours that form lumps. There are 4 stages. Often the stages 1 to 4 are written as the Roman numerals I, II, III and IV. Generally, the higher the stage number, the more the cancer has spread.

For retinoblastoma, the AJCC staging system includes information about both intraocular and extraocular retinoblastoma. It uses a variation of the TNM staging system by also considering inherited genetic mutations. The AJCC staging system for retinoblastoma uses the following 4 pieces of information.

T (tumour)– the size of the tumour and how far it has grown inside and outside of the eye.

N (nodes)– whether the cancer has spread to the lymph nodes in the head or neck.

M (metastasis)– whether the cancer has spread (metastasized) to distant parts of the body.

H (heritable)– whether there is a germline retinoblastoma 1 (RB1) gene mutation (called heritable retinoblastoma).

Recurrent retinoblastoma means that the cancer has come back after it has been treated.

If it comes back in the same place that the cancer first started, it’s called a local recurrence.

If it comes back in tissues or lymph nodes close to where it first started, it’s called a regional recurrence.

It can also recur in another part of the body. This is called distant metastasis or distant recurrence.