From: PIK3CA-activating mutations and chemotherapy sensitivity in stage II–III breast cancer
Patients with ER-negative breast cancer | Patients with ER-positive breast cancer | ||||||
---|---|---|---|---|---|---|---|
PIK3CA wild-type (n = 54) | PIK3CA mutation (n = 8) | P valuea | PIK3CA wild-type (n = 63) | PIK3CA mutation (n = 15) | P valuea | ||
Pathological complete response (pCR) versus residual disease (RD) | RD | 38 (72%) | 5 (71%) | 1.000 | 57 (92%) | 13 (87%) | 0.617 |
pCR | 15 (28%) | 2 (29%) | 5 (8%) | 2 (13%) | |||
Unknown | 1 | 1 | - | 1 | - | - | |
Residual cancer burden | 0 | 15 (34.1%) | 2 (50.0%) | 0.616 (0.527b) | 5 (10.6%) | 2 (18.2%) | 0.221 (0.543b) |
I | 3 (6.8%) | 0 (0%) | 4 (8.5%) | 0 (0%) | |||
II | 15 (34.1%) | 2 (50.0%) | 22 (46.8%) | 8 (72.7%) | |||
III | 11 (25.0%) | 0 (0%) | 16 (34.0%) | 1 (9.1%) | |||
Unknown | 10 | 4 | - | 16 | 4 | - | |
HER2 status | HER2- | 47 (87%) | 7 (88%) | 1.000 | 57 (90%) | 14 (93%) | 0.617 |
HER2+ | 7 (13%) | 1 (12%) | 6 (10%) | 1 (7%) | |||
Grade | Grade 1–2 | 9 (20%) | 2 (33%) | 0.598 | 37 (71%) | 8 (67%) | 0.739 |
Grade 3 | 36 (80%) | 4 (67%) | 15 (29%) | 4 (33%) | |||
Unknown | 9 | 2 | - | 11 | 3 | - | |
Nodal status | Negative | 15 (28%) | 4 (50%) | 0.235 | 14 (22%) | 8 (53%) | 0.025 |
Positive | 39 (72%) | 4 (50%) | 49 (78%) | 7 (47%) | |||
Tumor size | T0 | 0 (0%) | 0 (0%) | 0.937 | 1 (2%) | 1 (7%) | 0.715 |
T1 | 4 (7%) | 0 (0%) | 3 (5%) | 0 (0%) | |||
T2 | 26 (48%) | 4 (50%) | 33 (52%) | 8 (53%) | |||
T3 | 10 (18%) | 1 (12%) | 8 (13%) | 2 (13%) | |||
T4 | 14 (26%) | 3 (38%) | 18 (28%) | 4 (27%) | |||
Ethnicity | Asian | 1 (2%) | 0 (0%) | 0.326 | 1 (2%) | 1 (7%) | 0.478 |
Black | 6 (11%) | 2 (25%) | 5 (8%) | 0 (0%) | |||
Hispanic | 16 (30%) | 4 (50%) | 24 (38%) | 6 (40%) | |||
Caucasian | 31 (57%) | 2 (25%) | 33 (52%) | 8 (53%) | |||
Median age (minimum-maximum), years | 51 (28–73) | 56.5 (42–73) | - | 50 (28–73) | 52 (43–73) |