Table 1. Patient characteristics based on PIK3CA amplification.

Characteristics	All patients		Copy number gain (Polysomy + Amplification)*		Normal copy number		P†
	No.	%	No.	%	No.	%
Number of patients	125	100	14	13.9	87	86.1
Age, years Median (range)	52 (18-84)		61 (37-84)		50 (20-83)		0.023
Gender							0.487
Male	78	62.4	8	57.1	58	66.7
Female	47	37.6	6	42.9	29	33.3
Tumor size, cm Median (range)	14.1 (1.0-37.0)		18.5 (5.5-37.0)		12.25 (1.0-31.0)		0.040
0-5 cm	19	15.2	0	0	16	18.4
5-10 cm	26	20.8	3	21.4	18	20.7
10-15 cm	26	20.8	1	7.1	20	30.0
>15 cm	46	36.8	8	57.1	28	32.2
unknown	8	6.4	2	14.3	5	5.7
Histologic classification							0.063
Well- and De-differentiated	54	43.2	9	64.3	33	37.9
Well differentiated	45	36.0	7	50.0	30	34.5
Dedifferentiated	9	7.2	2	14.3	3	3.4
Mixoid/Round cell, Pleomorphic	71	58.8	5	35.7	54	62.1
Myxoid	52	41.6	2	14.3	44	50.6
Round cell	9	7.2	1	7.1	5	5.7
Pleomorphic	10	8.0	2	14.3	5	5.7
Primary tumor site							0.051
Extremity	61	48.8	4	28.6	46	52.9
Lower extremity	55	44.0	4	28.6	43	49.4
Upper extremity	6	4.8	0	0	3	3.4
Retroperitoneum/intraabdomen	35	28.0	8	57.1	18	20.7
Retroperitoneum	27	21.6	5	35.7	15	17.2
Intraabdomen	8	6.4	3	21.4	3	3.4
Inguinal area & genital organ	10	8.0	1	7.1	8	9.2
Other area	19	15.2	1	7.1	15	17.2
Time to recurrence, months Median (range)	22.0 (3.7-240.9)		13.8 (6.2-95.2)		34.4 (3.7-240.9)

Abbreviations: PIK3CA, phosphatidylinositol-4,5-bisphosphate 3-Kinase, Catalytic Subunit Alpha;CEN3, centromere3

^*PIK3CA amplification was defined as if one of the following criteria is fulfilled: (1) PIK3CA/CEN3 ratio is ≥ 2.0, (2) average number of PIK3CA signal per nucleus > 4.0

^*PIK3CA polysomy were defined as average number of PIK3CA signal per nucleus 4.0 ≥ to > 2.0.

^†χ² test, Fisher's exact test, t-test or Mann-Whitney U test.