Table 1.
Characteristics of breast cancer patients (N=105)
| Variables | Total, N (%) | CTC <5 N=73 | CTC ≥5 N=32 | P | Negative cHER2 N=86 | Positive cHER2 N=19 | P | Low-risk cHER2* N=90 | High-risk HER2 N=15 | P |
|---|---|---|---|---|---|---|---|---|---|---|
| Age (years), mean (SD) | 55.0 (11.4) | 55.0 (11.9) | 55.0 (10.4) | 0.979 | 54.8 (11.8) | 55.7 (9.4) | 0.775 | 55.0 (11.7) | 54.9 (9.6) | 0.990 |
| <54.6 | 52 (49.5) | 37 (50.7) | 15 (46.9) | 0.719 | 43 (50.0) | 9 (47.4) | 0.836 | 44 (48.9) | 8 (53.3) | 0.750 |
| ≥54.6 | 53 (50.5) | 36 (49.3) | 17 (53.1) | 43 (50.0) | 10 (52.6) | 46 (51.1) | 7 (46.7) | |||
| Ethnicity | ||||||||||
| Caucasian | 89 (84.8) | 62 (84.9) | 27 (84.4) | 0.329 | 73 (84.9) | 16 (84.2) | 0.701 | 76 (84.4) | 13 (86.7) | 0.403 |
| African American | 13 (12.4) | 10 (13.7) | 3 (9.4) | 11 (12.8) | 2 (10.5) | 12 (13.3) | 1 (6.7) | |||
| Other | 3 (2.9) | 1 (1.4) | 2 (6.3) | 2 (2.3) | 1 (5.3) | 2 (2.2) | 1 (6.7) | |||
| BMI (kg/m2) | ||||||||||
| <25 | 28 (26.7) | 22 (30.1) | 6 (18.8) | 0.318 | 25 (29.1) | 3 (15.8) | 0.372 | 27 (30.0) | 1 (6.7) | 0.112 |
| ≥25 – <30 | 35 (33.3) | 25 (34.3) | 10 (31.3) | 29 (33.7) | 6 (31.6) | 30 (33.3) | 5 (33.3) | |||
| ≥30 | 42 (40.0) | 26 (35.6) | 16 (50.0) | 32 (37.2) | 10 (52.6) | 33 (36.7) | 9 (60.0) | |||
| Menopause status | ||||||||||
| Post | 88 (83.8) | 61 (83.6) | 27 (84.4) | 0.917 | 71 (82.6) | 17 (89.5) | 0.732 | 75 (83.3) | 13 (86.7) | 1.000 |
| Pre | 17 (16.2) | 12 (16.4) | 5 (15.6) | 15 (17.4) | 2 (10.5) | 15 (16.7) | 2 (13.3) | |||
| Tumor stage | ||||||||||
| III | 15 (14.3) | 13 (17.8) | 2 (6.3) | 0.142 | 14 (16.3) | 1 (5.3) | 0.296 | 15 (16.7) | 0 (0) | 0.121 |
| IV | 90 (85.7) | 60 (82.2) | 30 (93.8) | 72 (83.7) | 18 (94.7) | 75 (83.3) | 15 (100) | |||
| Tumor grade | ||||||||||
| Moderately differentiated | 25 (23.8) | 18 (24.7) | 7 (21.9) | 0.017 | 21 (24.4) | 4 (21.1) | 0.190 | 21 (23.3) | 4 (26.7) | 0.274 |
| Poorly differentiated | 70 (66.7) | 52 (71.2) | 18 (56.3) | 59 (68.6) | 11 (57.9) | 62 (68.9) | 8 (53.3) | |||
| Unknown | 10 (9.5) | 3 (4.1) | 7 (21.9) | 6 (7.0) | 4 (21.1) | 7 (7.8) | 3 (20.0) | |||
| Tumor subtype | ||||||||||
| HR+ HER2− (Luminal) | 66 (62.9) | 41 (56.2) | 25 (78.1) | 0.032 | 52 (60.5) | 14 (73.7) | 0.281 | 55 (61.1) | 11 (73.3) | 0.364 |
| HR− HER2− (Triple negative) | 39 (37.1) | 32 (43.8) | 7 (21.9) | 34 (39.5) | 5 (26.3) | 35 (38.9) | 4 (26.7) | |||
| Baseline cancer antigen 15.3 | ||||||||||
| Normal | 13 (12.4) | 9 (12.3) | 4 (12.5) | 0.473 | 11 (12.8) | 2 (10.5) | 0.213 | 12 (13.3) | 1 (6.7) | 0.476 |
| Elevated | 22 (21.0) | 13 (17.8) | 9 (28.1) | 15 (17.4) | 7 (36.8) | 17 (18.9) | 5 (33.3) | |||
| Unknown | 70 (66.7) | 51 (69.9) | 19 (59.4) | 60 (69.8) | 10 (52.6) | 61 (67.8) | 9 (60.0) | |||
| Number of previous hormone therapy lines | ||||||||||
| 0 | 62 (59.1) | 47 (64.4) | 15 (46.9) | 0.045 | 53 (61.6) | 9 (47.4) | 0.179 | 56 (62.2) | 6 (40.0) | 0.105 |
| 1 | 17 (16.2) | 13 (17.8) | 4 (12.5) | 15 (17.4) | 2 (10.5) | 15 (16.7) | 2 (13.3) | |||
| ≥2 | 26 (24.8) | 13 (17.8) | 13 (40.6) | 18 (20.9) | 8 (42.1) | 19 (21.1) | 7 (46.7) | |||
| Number of previous chemotherapy lines | ||||||||||
| 0 | 32 (30.5) | 22 (30.1) | 10 (31.3) | 0.215 | 28 (32.6) | 4 (21.1) | 0.614 | 29 (32.2) | 3 (20.0) | 0.339 |
| 1 | 24 (22.9) | 20 (27.4) | 4 (12.5) | 19 (22.1) | 5 (26.3) | 22 (24.4) | 2 (13.3) | |||
| ≥2 | 49 (46.7) | 31 (42.5) | 18 (56.3) | 39 (45.4) | 10 (52.6) | 39 (43.3) | 10 (66.7) | |||
| Hormonal therapy | ||||||||||
| No | 52 (49.5) | 39 (53.4) | 13 (40.6) | 0.227 | 41 (47.7) | 11 (57.9) | 0.420 | 44 (48.9) | 8 (53.3) | 0.750 |
| Yes | 53 (50.5) | 34 (46.6) | 19 (59.4) | 45 (52.3) | 8 (42.1) | 46 (51.1) | 7 (46.7) | |||
| Chemotherapy | ||||||||||
| No | 21 (20.0) | 17 (23.3) | 4 (12.5) | 0.203 | 19 (22.1) | 2 (10.5) | 0.351 | 19 (21.1) | 2 (13.3) | 0.730 |
| Yes | 84 (80.0) | 56 (76.7) | 28 (87.5) | 67 (77.9) | 17 (89.5) | 71 (78.9) | 13 (86.7) | |||
| Targeted therapy | ||||||||||
| No | 38 (36.2) | 28 (38.4) | 10 (31.3) | 0.486 | 30 (34.9) | 8 (42.1) | 0.553 | 32 (35.6) | 6 (40.0) | 0.740 |
| Yes | 67 (63.8) | 45 (61.6) | 22 (68.7) | 56 (65.1) | 11 (57.9) | 58 (64.4) | 9 (60.0) |
Abbreviations: BMI, body mass index; CTC, circulating tumor cell; cHER2, human epidermal growth factor receptor 2 phenotype on circulating tumor cell; HR, hormonal
receptors; SD, standard deviation.
*
cHER2+ <2, including those with negative cHER2