Table 2.
Course of treatment
|
BCS (n = 212) |
M (n = 27) |
MIBR (n = 86) |
p-value* | ||||
|---|---|---|---|---|---|---|---|
| Residual tumor◊ n (%)** | 209 | (98.6%) | 27 | (100%) | 81 | (94.2%) | ≈0.009 |
| R0 (no residual tumor) | 161a | (77.0%) | 27b | (100%) | 69a | (85.2%) | |
| R1 (microscopic residual tumor) | 48a | (23.0%) | 0b | (0.0%) | 12a | (14.8%) | |
| Re-operation• n (%)** | 212 | (100%) | 27 | (100%) | 86 | (100%) | ≈0.022 |
| Yes | 61a, b | (28.8%) | 3b | (11.1%) | 33a | (38.4%) | |
| No | 151a, b | (71.2%) | 24b | (88.9%) | 53a | (61.6%) | |
| More invasive re-operation• n (%)** | 212 | (100%) | 27 | (100%) | 86 | (100%) | ≈0.289 |
| Yes | 15 | (7.1%) | 0 | (0.0%) | 4 | (4.7%) | |
| No | 197 | (92.9%) | 27 | (100%) | 82 | (95.3%) | |
| Axillary surgery n (%)** | 212 | (100%) | 27 | (100%) | 86 | (100%) | < 0.001F |
| None | 34a | (16.0%) | 4b | (14.8%) | 12a | (14.0%) | |
| SLNB | 152a | (71.7%) | 8b | (29.6%) | 55a | (64.0%) | |
| Axillary sample | 2a | (0.9%) | 1b | (3.7%) | 1a | (1.2%) | |
| ALND | 24a | (11.3%) | 14b | (51.9%) | 18a | (20.9%) | |
| Radiotherapy n (%)** | 212 | (100%) | 27 | (100%) | 86 | (100%) | < 0.001 |
| Yes | 175a | (82.5%) | 13b | (48.1%) | 20c | (23.3%) | |
| No | 37a | (17.5%) | 14b | (51.9%) | 66c | (76.7%) | |
| Chemotherapy n (%)** | 212 | (100%) | 27 | (100%) | 86 | (100%) | < 0.001 |
| Yes | 78a | (36.8%) | 11a | (40.7%) | 54b | (62.8%) | |
| No | 134a | (63.2%) | 16a | (59.3%) | 32b | (37.2%) | |
| Targeted therapy n (%)** | 212 | (100%) | 27 | (100%) | 86 | (100%) | ≈0.087 |
| Yes | 22 | (10.4%) | 3 | (11.1%) | 17 | (19.8%) | |
| No | 190 | (89.6%) | 24 | (88.9%) | 69 | (80.2%) | |
| Endocrine therapy n (%)** | 212 | (100%) | 27 | (100%) | 86 | (100%) | ≈0.853 |
| Yes | 127 | (59.9%) | 15 | (55.6%) | 53 | (61.6%) | |
| No | 85 | (40.1%) | 12 | (44.4%) | 33 | (38.4%) | |
SLNB Sentinel lymph node biopsy, ALND Axillary lymph node dissection
*Chi2-test was performed to test for group differences. Exceptions are indicated. In case of a p value below 0.05, a z-test for column proportions was performed as post-hoc-test
FFisher’s exact test was performed to test for group differences. In case of a p value below 0.05, a Fisher’s exact test for pairwise comparison was performed as post-hoc-test
a, b, c Same letters indicate that the post-hoc test for two study groups (i.e. their values) had a p value above 0.05
**Number of patients per group with available data. Available data < full group size indicates missing data
◊Refers to resection status after reference breast surgery (that group allocation was based on)
•“Re-operations” are all surgeries performed after the initial breast surgery.”More invasive re-operations” are only the type of re-operations that for their more invasive character did not match the allocated surgical group anymore (M more invasive than MIBR, MIBR more invasive than BCS)