Eye Cancer: Uveal Melanoma

Uveal Melanoma Staging

(source: American Joint Committee on Cancer)

If you are diagnosed with eye cancer, your doctor will determine the stage of the disease. Staging is a way of classifying how much disease is in the body and where it has spread when it is diagnosed. This information helps your doctor plan the best type of treatment for you. Once the staging classification is determined, it stays the same even if treatment is successful or the cancer spreads.

The most common staging system used for ocular cancers was developed by the American Joint Committee on Cancer (AJCC).  The TNM system is based on three key pieces of information:

• T describes the size of the primary tumor and/or whether it has invaded nearby structures
• N describes whether the cancer has spread to nearby (regional) lymph nodes
• M indicates whether the cancer has metastasized (spread) to other parts of the body (The most common site of eye melanoma spread is the liver)

Numbers or letters appear after T, N and M to provide more details about each of these factors:

• The numbers 0 through 4 indicate increasing severity
• The letter X means "cannot be assessed" because the information is not available.

The N and M categories are the same for all uveal melanomas (iris, ciliary body or choroid). The T categories, however, are different for these locations.

T categories for iris melanoma:

• TX: The main (primary) tumor cannot be assessed; information not known
• T0: No evidence of a primary tumor
• T1: Tumor is only in the iris
• T1a: The tumor is only in the iris and touches 1/4 or less of the iris
• T1b: The tumor is only in the iris and touches more than 1/4 of the iris
• T1c: The tumor is only in the iris and is causing an increase in the eye pressure (glaucoma)
• T2: Tumor has grown into the ciliary body or choroid (or both)
• T2a: Tumor has grown into the ciliary body and/or choroid and is causing glaucoma
• T3: Tumor has grown into the ciliary body and/or choroid and into the sclera
• T3a: Tumor has grown into the ciliary body and/or choroid and into the sclera and is causing glaucoma
• T4: Tumor extends outside the eyeball
• T4a: The part of the tumor that is outside the eyeball is 5 millimeters (about 1/5 of an inch) or less across in size
• T4b: The part of the tumor that is outside the eyeball is greater than 5 millimeters (about 1/5 of an inch) in size

T categories for ciliary body and choroidal melanoma: 

• TX: The main (primary) tumor cannot be assessed; information not known
• T0: No evidence of a primary tumor
• T1: Tumor size is either:
  • No more than 3millimeters deep and no more than 12 millimeters across, OR
  • From 3.1 to 6 millimeters deep and no more than 9 millimeters across
• T1a: The tumor is T1 in size and is not growing into the ciliary body or growing outside the eyeball
• T1b: The tumor is T1 in size and is growing into the ciliary body
• T1c: The tumor is T1 in size and is not growing into the ciliary body but is growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size
• T1d: The tumor is T1 in size and is growing into the ciliary body. It is also growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size
• T2: Tumor size is one of the following:
  • No more than 3millimeters deep and from 12.1 to 18.0 millimeters across
  • From 3.1 to 6 millimeters deep and 9.1 to 15 millimeters across
  • From 6.1 to 9.0 millimeters deep and no more than 12.0 millimeters across
• T2a: The tumor is T2 in size and is not growing into the ciliary body or growing outside the eyeball
• T2b: The tumor is T2 in size and is growing into the ciliary body
• T2c: The tumor is T2 in size and is not growing into the ciliary body but is growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size
• T2d: The tumor is T2 in size and is growing into the ciliary body. It is also growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size
• T3: Tumor size is one of the following:
  • 3.1 to 6 millimeters deep and between 15.1 and 18 millimeters across
  • 6.1 to 9.0 millimeters deep and between 12.1 and 18 millimeters across
  • From 9.1 to 12 millimeters deep and 18 millimeters or less across
  • From 12.1 to 15 millimeters deep and 15 millimeters or less across
• T3a: The tumor is T3 in size and is not growing into the ciliary body or growing outside the eyeball
• T3b: The tumor is T3 in size and is growing into the ciliary body
• T3c: The tumor is T3 in size and is not growing into the ciliary body but is growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size
• T3d: The tumor is T3 in size and is growing into the ciliary body. It is also growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size.
• T4: Tumor size is one of the following:
  • Greater than 15 millimeters deep and any width
  • Greater than 18 millimeters across and any depth
  • Between 12.1 and 15.0 millimeters deep and between 15.1 and 18 millimeters across
• T4a: The tumor is T4 in size and is not growing into the ciliary body or growing outside the eyeball
• T4b: The tumor is T4 in size and is growing into the ciliary body
• T4c: The tumor is T4 in size and is not growing into the ciliary body but is growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size
• T4d: The tumor is T4 in size and is growing into the ciliary body. It is also growing outside of the eyeball. The part of the tumor that is outside the eyeball is 5millimeters (about 1/5 of an inch) or less across in size
• T4e: The tumor is growing outside the eyeball with the part of the tumor that is outside the eyeball greater than 5millimeters across. The tumor can be any size.

N categories for iris, ciliary body and choroidal melanomas:

• NX: Lymph nodes cannot be assessed
• N0: Cancer has not spread to nearby lymph nodes
• N1: Cancer has spread to nearby lymph nodes.

M categories for iris, ciliary body, and choroidal melanomas:

• M0: Cancer has not spread to distant parts of the body
• M1: Cancer has spread to distant parts of the body
• M1a: The largest area of cancer spread is 3 centimeters (a little over an inch) across or smaller
• M1b: The largest area of cancer spread is between 3.1 and 8 centimeters across (8 centimeters is a little over 3 inches)
• M1c: The largest area of cancer spread is 8 centimeters or more across.