Exploring the Value of Additional Primary Tumour Excision Combined with Systemic Therapy Administered in Different Sequences for Patients with de Novo Metastatic Breast Cancer
Table 1
Demographic, clinicopathologic, and treatment characteristics of the included patients.
Variables
All patients (N = 15012)
Systemic therapy without primary surgery (N = 10774)
Systemic therapy after primary surgery (N = 2948)
Systemic therapy before primary surgery (N = 1290)
Age, y
(18, 40)
1271 (8.5)
907 (8.4)
221 (7.5)
143 (11.1)
(40, 60)
6244 (41.6)
4511 (41.9)
1079 (36.6)
654 (50.7)
(60, 100)
7497 (49.9)
5356 (49.7)
1648 (55.9)
493 (38.2)
Median (IQR)
59 (50–68)
59 (50–68)
62 (51–71)
56 (47–64)
Marital status
Unmarried
7199 (48.0)
5244 (48.7)
1359 (46.1)
596 (46.2)
Married
7125 (47.5)
5058 (46.9)
1445 (49.0)
622 (48.2)
Unknown
688 (4.6)
472 (4.4)
144 (4.9)
72 (5.6)
Race
White
11197 (74.6)
7938 (73.7)
2316 (78.6)
943 (73.1)
Black
2415 (16.1)
1794 (16.7)
397 (13.5)
224 (17.4)
Other
1333 (8.9)
985 (9.1)
228 (7.7)
120 (9.3)
Unknown
67 (0.4)
57 (0.5)
7 (0.2)
3 (0.2)
Sex
Female
14831 (98.8)
10666 (9.0)
2889 (98.0)
1276 (98.9)
Male
181 (1.2)
108 (1.0)
59 (2.0)
14 (1.1)
Histologic type
IDC
10644 (70.9)
7494 (69.6)
2125 (72.1)
1025 (79.5)
ILC
1499 (10.0)
1042 (9.7)
368 (12.5)
89 (6.9)
Other
2869 (19.1)
2238 (20.8)
455 (15.4)
176 (13.6)
Grade
I
937 (6.2)
636 (5.9)
214 (7.3)
87 (6.7)
II
5094 (33.9)
3582 (33.2)
1095 (37.1)
417 (32.3)
III/IV
6110 (40.7)
4053 (37.6)
1398 (47.4)
659 (51.1)
Unknown
2871 (19.1)
2503 (23.2)
241 (8.2)
127 (9.8)
AJCC T category
0
240 (1.6)
237 (2.2)
2 (0.1)
1 (0.1)
1
1802 (12.0)
1206 (11.2)
480 (16.3)
116 (9.0)
2
4390 (29.2)
2776 (25.8)
1257 (42.6)
357 (27.7)
3
2305 (15.4)
1534 (14.2)
532 (18.0)
239 (18.5)
4
4405 (29.3)
3319 (30.8)
576 (19.5)
510 (39.5)
X
1870 (12.5)
1702 (15.8)
101 (3.4)
67 (5.2)
AJCC N category
0
3199 (21.3)
2369 (22.0)
628 (21.3)
202 (15.7)
1
6764 (45.1)
5242 (48.7)
925 (31.4)
597 (46.3)
2
1649 (11.0)
816 (7.6)
620 (21.0)
213 (16.5)
3
2278 (15.2)
1378 (12.8)
665 (22.6)
235 (18.2)
X
1122 (7.5)
969 (9.0)
110 (3.7)
43 (3.3)
Molecular subtype
HR+/HER2−
7862 (52.4)
5428 (50.4)
1828 (62.0)
606 (47.0)
HR+/HER2+
2534 (16.9)
1908 (17.7)
412 (14.0)
214 (16.6)
HR−/HER2+
1422 (9.5)
1067 (9.9)
214 (7.3)
141 (10.9)
HR−/HER2−
2037 (13.6)
1448 (13.4)
334 (11.3)
255 (19.8)
Unknown
1157 (7.7)
923 (8.6)
160 (5.4)
74 (5.7)
Bone involvement
No
3856 (25.7)
2599 (24.1)
812 (27.5)
445 (34.5)
Yes
11156 (74.3)
8175 (75.9)
2136 (72.5)
845 (65.5)
Lung involvement
No
9791 (65.2)
6796 (63.1)
2125 (72.1)
870 (67.4)
Yes
5221 (34.8)
3978 (36.9)
823 (27.9)
420 (32.6)
Liver involvement
No
10438 (69.5)
7160 (66.5)
2270 (77.0)
1008 (78.1)
Yes
4574 (30.5)
3614 (33.5)
678 (23.0)
282 (21.9)
Brain involvement
No
13746 (91.6)
9696 (90.0)
2814 (95.5)
1236 (95.8)
Yes
1266 (8.4)
1078 (10.0)
134 (4.5)
54 (4.2)
Site of metastasis
Bone only
6214 (41.4)
4056 (37.6)
1537 (52.1)
621 (48.1)
Viscera only
3415 (22.7)
2249 (20.9)
755 (25.6)
411 (31.9)
Bone + viscera
4117 (27.4)
3391 (31.5)
522 (17.7)
204 (15.8)
Brain involvement
1266 (8.4)
1078 (10.0)
134 (4.5)
54 (4.2)
Number of sites of metastasis
1
9447 (62.9)
6153 (57.1)
2264 (76.8)
1030 (79.8)
2
4121 (27.5)
3355 (31.1)
555 (18.8)
211 (16.4)
≥3
1444 (9.6)
1266 (11.8)
129 (4.4)
49 (3.8)
Vital status
Alive
6761 (45.0)
4903 (45.5)
1250 (42.4)
608 (47.1)
Dead of breast cancer
7319 (48.8)
5228 (48.5)
1478 (50.1)
613 (47.5)
Dead of other cause
932 (6.2)
643 (6.0)
220 (7.5)
69 (5.3)
Radiation therapy
None/unknown
10246 (68.3)
7673 (71.2)
1896 (64.3)
677 (52.5)
Yes
4766 (31.7)
3101 (28.8)
1052 (35.7)
613 (47.5)
Non-primary surgical procedure to distant site
No
14409 (96.0)
10358 (96.1)
2811 (95.4)
1240 (96.1)
Yes
475 (3.2)
66 (0.6)
40 (1.4)
22 (1.7)
Unknown
128 (0.9)
350 (3.2)
97 (3.3)
28 (2.2)
Surgical procedure
Partial mastectomy
1111 (37.7)
249 (19.3)
Subcutaneous/simple mastectomy
707 (24.0)
416 (32.2)
Modified radical mastectomy
1054 (35.8)
574 (44.5)
(Extended) radical mastectomy
34 (1.2)
19 (1.5)
Unknown
42 (1.4)
32 (2.5)
Abbreviations: IQR, interquartile range; IDC, invasive ductal carcinoma; ILC, invasive lobular carcinoma; HR, hormone receptor; HER2, human epidermal growth factor receptor 2. -value for comparison of categorical variables across groups is 0.03 for marital status, 0.001 for vital status, and <0.001 for other variables.
