Table II.

Iris melanoma primary tumor (T) classification according to the American Joint Cancer Committee (AJCC 8th edition) (59).

Primary tumor (T) classification	Explanation	Sub-stages
T1	Tumor limited to the iris	T1a: not >3 clock hours in size
		T1b: >3 clock hours in size
		T1c: T1 with secondary glaucoma
T2	Tumor confluent with or extending into the ciliary body, choroid, or both	T2a: Confluent with or extending into the ciliary body, without secondary glaucoma
		T2b: Confluent with or extending into the ciliary body and choroid without secondary glaucoma
		T2c: Confluent with or extending into the ciliary body, choroid, or both, with secondary glaucoma
T3	Tumor confluent with or extending into the ciliary body, choroid, or both, with scleral extension
T4	Tumor with extrascleral extension	T4a: Extrascleral extension ≤5 mm in diameter
		T4b: Extrascleral extension >5 mm in diameter

The information presented in the table is derived from a previous study (59).