Table 3. Risk assessment of GIST, 2002 by NIH.

Risk category	Size (cm)	Mitotic count (50 HPF)
Very low risk	<2	<5
Low risk	2-5	5
Intermediate risk	5	6-10
	5-10	5
High risk	>5	>5
	>10	Any mitotic rate
	Any size	>10

Adopted from Fletcher and colleagues [ref (99) Table 2]. Abbreviations: HPF, high-power field