SNB False-Negative Rates: Results of Large Multiinstitutional Trials
| Trial | Exclusion criteria | Sentinel node identified | Evaluable patients (SNB + ALND) | Node-positive patients | False-negative rate | Tracers and injection sites | Procedure |
| SNAC (19) | Tumor > 3 cm, or multifocal | 93.5% | 539 | 145 (29%) | 5.5% (8/145) | 99mTc-antimony sulfide colloid peritumoral; +patent blue V peritumoral | Scintigraphy and γ-probe + blue dye |
| ALMANAC validation study (20) | 96.1% | 803 | 282 (35.1%) | 6.7% (19/282) | 99mTc-nanocolloidal albumin peritumoral; +patent blue V peritumoral | Scintigraphy and γ-probe + blue dye | |
| NSABP-B32 (21) | 97.2% | 2,619 | 766 (29.2%) | 9.8% (75/766) | Unfiltered 99mTc-sulfur colloid peritumoral (+1 intradermal); +isosulfan blue peritumoral | γ-probe + blue dye | |
| Sentinella/GIVOM (16) | >3 cm, multifocal, or unpalpable | 95% | 323 | 108 (33.4%) | 16.7% (18/108) | 99mTc-nanocolloidal albumin subdermally; no blue dye | Scintigraphy and γ-probe |
| Total | ∼96% | 4,284 | 1,301 (30.4%) | 9.2% (120/1,301) |
SNAC = sentinel node biopsy versus axillary clearance.
A single-center study (71) that was interrupted prematurely, with only 115 evaluated patients, was not included in these data.