Table 2. Estimates of the cumulative incidence of thrombosis.

	N	No of thrombosis events	12-Month estimate (percent)	95% Confidence interval	P-value
All	290	25	8.5	(5.5, 12.4)	—
Baseline CTC
0	108	3	3.0	(0.8, 7.9)
⩾1	182	22	11.7	(7.3, 17.3)	0.006
Baseline CTC
<5	177	11	6.6	(3.3, 11.4)
⩾5	113	14	11.6	(6.3, 18.6)	0.076
Age (years)
<50	100	10	8.9	(4.1, 15.9)
>50	190	15	8.3	(4.7, 13.2)	0.552
Line of therapy
1	123	6	3.3	(1.1, 7.8)
⩾2	167	19	12.8	(7.8, 19.1)	0.027
Estrogen and progesteron receptor
Positive for both	192	14	6.4	(3.4, 10.8)
Negative for either	98	11	12.8	(6.7, 21.0)	0.188
HER2/neu amplified
No	227	20	8.4	(5.1, 12.8)
Yes	62	5	8.8	(3.2, 18.1)	0.900
Inflammatory breast cancer
No	222	17	7.9	(4.7, 12.1)
Yes	68	8	11.1	(4.3, 21.3)	0.234
Visceral metastasis
No	109	2	2.0	(0.4, 6.3)
Yes	181	23	12.3	(7.8, 18.0)	0.002
Bone metastasis
No	88	6	8.6	(3.4, 16.9)
Yes	202	19	8.6	(5.1, 13.2)	0.547
Number of sites of metastasis
1	100	3	3.53	(0.9, 9.2)
2 or 3	144	11	7.69	(3.9, 13.2)
⩾4	46	11	21.07	(10.2, 34.5)	0.002
Chemotherapy
No	36	3	5.6	(1.0, 16.5)
Yes	254	22	8.8	(5.6, 13.0)	0.934
Bevacizumab-based therapy
No	230	20	8.1	(4.9, 12.4)
Yes	60	5	10.0	(3.5, 20.5)	0.999
Hormonal therapy
No	164	19	11.9	(7.2, 18.0)
Yes	126	6	4.2	(1.6, 8.9)	0.037
Tamoxifen
No	101	10	10.4	(5.3, 17.5)
Yes	38	1	0.0	—	0.177
Aromatase inhibitors
No	194	22	11.2	(7.0, 16.6)
Yes	96	3	3.2	(0.9, 8.3)	0.016
Erythropoetin-stimulating agents
No	256	24	9.3	(5.9, 13.6)
Yes	34	1	2.9	(0.2, 13.2)	0.150
Port-a-catheter and/or central venous device
No	211	17	7.9	(4.6, 12.4)
Yes	79	8	9.8	(4.2, 18.1)	0.747
History of DVT/PE
No	274	23	8.0	(5.1, 11.9)
Yes	16	2	14.6	(2.0, 38.7)	0.672
Arterial hypertension
No	188	19	9.1	(5.4, 13.9)
Yes	102	6	7.5	(3.0, 14.8)	0.242
Diabetes mellitus
No	255	22	8.5	(5.3, 12.6)
Yes	35	3	8.9	(2.2, 21.6)	0.924

Abbreviations: DVT=deep vein thrombosis; PE= pulmonary embolism, CTC=circulating tumour cells.