Table 1.

Nonconditional and conditional analysis of probability for development of new tumors in ipsilateral or contralateral eye in 482 patients presenting with solitary unilateral retinoblastoma

Age at diagnosis (months)	Nonconditional risk at presentation Total, n (%)	Conditional risk at each subsequent time point while maintaining solitary unilateral retinoblastoma									Age of latest initial new tumors (months)
		At 6 months, n (%)	At 9 months, n (%)	At 12 months, n (%)	At 18 months, n (%)	At 24 months, n (%)	At 30 months, n (%)	At 36 months, n (%)	At 48 months, n (%)	At 60 months, n (%)
0-3 (n=23)	8 (39)	4 (25)	2 (15)	2 (15)	1 (8)	0	0	0	0	0	18.7
>3-6 (n=25)	5 (21)	4 (17)	3 (14)	1 (6)	1 (6)	0	0	0	0	0	18.2
>6-9 (n=40)	2 (6)		2 (6)	2 (6)	0	0	0	0	0	0	17.8
>9-12 (n=37)	1 (3)			1 (3)	1 (3)	0	0	0	0	0	23.4
>12-24 (n=112)	0					0	0	0	0	0	NA
>24-36 (n=91)	2 (2)							1 (1)	0	0	46.1
>36 (n=119)	2 (2)								1 (1)	0	55.9

NA: Not applicable