The Potential Malignancy of a Solitary Fibrous Tumour of the Lung

Table 1

Risk stratification model [14].

Risk factor	Score
Age
<55	0
≥55	1
Tumour size (cm)
<5	0
5 to <10	1
10 to <15	2
≥15	3
Mitotic figures (/10 high-power fields)
0	0
1–3	1
≥4	2
Risk	Total score
Low	0–2
Moderate	3-4
High	5-6