Anatomical distribution of bone metastases in stage IV breast cancer: According to histological subtype

Table 5 Anatomical distribution of first bone metastasis according to hormone receptor, n (%)

First bone metastasis	ER (n = 94)	PR (n = 59)	HER 2 (n = 16)	P value
Skull bones	3/94 (3.2)	1/59 (1.7)	0	1.00
Scapula and clavicle	4/94 (4.2)	3/59 (5)	1/16 (6.2)	0.93
Sternum	9/94 (9.6)	5/59 (8.5)	4/16 (25)	0.14
Humerus	16/94 (17.0)	10/59 (16.9)	2/16 (12.5)	0.89
Ribs	26/94 (28.0)	14/59 (24.1)	6/16 (37.5)	0.56
Cervical vertebra	15/94 (16.0)	10/59 (16.9)	3/16 (18.8)	0.96
Thoracic vertebra	41/94 (43.6)	23/59 (38.9)	8/16 (50)	0.62
Lumbar vertebra	45/94 (47.9)	25/59 (42.4)	8/16 (50)	0.76
Sacrum	19/94 (20.2)	10/59 (16.9)	2/16 (12.5)	0.72
Pelvic bones (ilium, ischium, pubis)	48/94 (51.1)	27/59 (45.8)	8/16 (50)	0.81
Femoral head and neck	25/94 (26.6)	18/59 (30.5)	7/16 (43.8)	0.37
Femoral shaft and distal femur	23/94 (24.7)	16/59 (27.6)	6/16 (37.5)	0.56