Group

Description

Prognosis

I

1) Solitary tumor, <4 disc diameters in size, at or posterior to the equator of the eye (an imaginary line in the coronal plane that marks the division between the anterior and posterior halves of the eye);

2) Multiple tumors, none > 4 disc diameters in size, all at or behind the equator.

Very favorable

II

1) Solitary tumor, 4 - 10 disc diameters in size, at or behind the equator;

2) Multiple tumors, 4 - 10 disc diameters in size, behind the equator.

Favorable

III

1) Any lesion anterior to the equator;

2) Solitary tumors > 10 disc diameters behind the equator.

Doubtful

IV

1) Multiple tumors, some > 10 disc diameters in size;

2) Any lesion extending anteriorly to the ora serrata.

Unfavorable

V

1) Massive tumors involving over half of the retina;

2) Vitreous seeding.

Very unfavorable