Evaluation of Two Different Analytical Methods for Circulating Tumor Cell Detection in Peripheral Blood of Patients with Primary Breast Cancer

Table 2

Baseline characteristics of patients for whom CTC detection after adjuvant chemotherapy was performed using the Cell Search System (CSS) or using manual immunocytochemistry (MICC).

Variable	CSS; 𝑁=1598	MICC; 𝑁=1066	𝑃-value^1
Age (years)			0.875^2
Median	53.0	53.0
Range	21–76	22–79
Tumor stage			0.842^3
pT1	660 (41.3%)	440 (41.3%)
pT2	824 (51.6%)	549 (51.5%)
pT3	86 (5.4%)	62 (5.8%)
pT4	22 (1.4%)	11 (1.0%)
unknown	6 (0.4%)	4 (0.4%)
Nodal stage			0.561^3
pN0	544 (34.0%)	383 (35.9%)
pN1	731 (45.7%)	475 (44.6%)
pN2	221 (13.8%)	151 (14.2%)
pN3	102 (6.4%)	57 (5.3%)
Histological grading			0.691^3
G1	72 (4.5%)	48 (4.5%)
G2	770 (48.2%)	531 (49.8%)
G3	751 (47.0%)	483 (45.3%)
unknown	5 (0.3%)	4 (0.4%)
Histological type			0.919^3
ductal	1290 (80.7%)	864 (81.1%)
lobular	191 (12.0%)	122 (11.4%)
other	113 (7.1%)	77 (7.2%)
unknown	4 (0.3%)	3 (0.3%)
Estrogen receptor status			0.968^3
negative	482 (30.2%)	322 (30.2%)
positive	1113 (69.6%)	741 (69.5%)
unknown	3 (0.2%)	3 (0.3%)
Progesterone receptor status			0.587^3
negative	549 (34.4%)	377 (35.4%)
positive	1045 (65.4%)	686 (64.4%)
unknown	4 (0.3%)	3 (0.3%)
HER2 status			0.077^3
negative	1173 (73.4%)	811 (76.1%)
positive	398 (24.9%)	233 (21.9%)
unknown	27 (1.7%)	22 (2.1%)
Menopausal status			0.775^3
premenopausal	688 (43.1%)	453 (42.5%)
postmenopausal	910 (56.9%)	613 (57.5%)
Type of surgery			0.647^3
breast conserving	1134 (71.0%)	747 (70.1%)
mastectomy	461 (28.8%)	316 (29.6%)
unknown	3 (0.2%)	3 (0.3%)
Adjuvant chemotherapy			0.624^3
FEC-DG	780 (48.8%)	510 (47.8%)
FEC-DOC	818 (51.2%)	556 (52.2%)

1All tests without unknowns.
²Mann-Whitney 𝑈 test.
³Chi-square test.
FEC-DG: 3 cycles of fluorouracil-epirubicin-cyclophosphamide followed by 3 cycles of docetaxel and gemcitabine; FEC-DOC: 3 cycles of fluorouracil-epirubicin-cyclophosphamide followed by 3 cycles of docetaxel.