Table 1.

Summary of published studies reporting malignant transformation after histological diagnosis of GCTB.

Ref.	NoP	Malignancies n (%)	Primary	Secondary	Time to Malignant Transformation	FU
Rutkowski et al. [3]	222	4 (1.8%)	-	4	3.5 yr	Median 13 mo
Bertoni F. et al. [4]	924	17 (1.8%)	5	12	Average l9 yr	NR
Domovitov SV et al. [5]	275	31 (11.3%)	26	5	NR	31 yr
Liu W et al. [6]	1365	32 (2.3%)	12	20	Secondary 7.9 yr Primary: NR	9.5 yr
Chawla et al. [7,8]	526	5 (1%)	4	1	74.5 mo	Median 58.1 mo
Agarwal et al. [9]	25	1 (4%)	-	1	8 mo	27 mo
Treffel et al. [10]	35	1 (2.9%)	-	1	18 mo	NR
Perrin et al. [11]	25	1 (4%)	-	1	55 mo	Median 57 mo
Palmerini et al. [12]	532	14 (2.6%)	5	9	7.8 yr	58 mo

FU: follow-up; GCTB: giant cell tumour of bone; mo: months; n: number; NoP: numbers of patients; NR: not reported; Ref: references; yr: years.