Risk of Completion ALND and Risk of Missed Axillary Disease After Negative Sentinel Node in Different Clinical Settings
| Trial | Category | Patients SNB + ALND | Sentinel node not identified | Positive SNB cases | Completion ALND required* | SNB false-negative rate | Estimates of residual disease after negative sentinel node |
| ALMANAC validation study (20) | T1 (≤2 cm) | 458 | 3.5% (16) | 27.9% (128) | 31.4% (144) | 5.2% (7/135) | 2.2% (7/314) |
| T2 (2.1–5 cm) | 235 | 3.4% (8) | 51.1% (120) | 54.5% (128) | 7.7% (10/130) | 9.3% (10/107) | |
| NSABP B32† (21) | T1 | 2,201 | 3%† (65†) | 21.4% (472) | 24.4% (537†) | 10.3% (54/526) | 3.2% (54/1,664†) |
| 2.1–4 cm | 490 | 1.6%† (8†) | 39.6% (194) | 41.2% (202†) | 8.9% (19/213) | 6.6% (19/288†) | |
| ALMANAC validation study (20) | Multifocal lesions | 75 | 5.3% (4) | 41.3% (31/75) | 46.7% (35/75) | 8.8% (3/34) | 7.5% (3/40) |
| IGASSU (37) | Multicentric or multifocal | 211‡ | 6.6% (14) | 42.2% (89) | 48.8% | 13.6% (14/103) | 12.9% (14/108) |
| Neoadjuvant (40) | Neoadjuvant chemotherapy | 195 | 9.7% (19) | 23.6% (46) | 33.3% (65) | 11.5% (6/52) | 4.6% (6/130) |
↵* Completion ALND is theoretically required when sentinel node is positive or not identified. Numbers are extracted from Tables 1 and 4 of ALMANAC (20). Data are based on patients with available information on tumor size. Only 12 patients had T3 tumor, not allowing comparison.
↵† Numbers are extracted from Tables 1, 2, and 4 of NSABP B-32 (21). Rate of failed sentinel node identification is an approximation based on data from both arms combined.
↵‡ Injection was subareolar; 62% had dual mapping, and 37% had only radioisotope.
Data were extracted from ALMANAC validation phase (20), NSABP B-32 trial (group SNB + ALND) (21), IGASSU trial (Interest of Axillary Sentinel Lymph Node Biopsy in Multiple Invasive Breast Cancer) (37), and “Ganglion Sentinelle et Chimiothérapie Néoadjuvante” trial (40).