Background: Sentinel node (SN) biopsy is widely used to stage breast carcinoma and, when positive, typically leads to axillary clearance (AC).
Aims: This study assesses clinicopathologic features of grade 1 breast carcinoma SNs with the aim of identifying a group of patients, who are likely to have a negative AC and can, therefore, safely be spared further surgery.
Results: Two hundred and forty-seven patients with grade 1 invasive carcinoma were identified, of whom 29 had a positive SN. Four patients (13.8%) had a positive AC. Positive AC occurred in 3 of 6 (50%) patients whose SN showed extranodal extension (EE), but in only 1 of 23 (4.3%) patients without EE. All patients were staged as pN1(sn) following SN biopsy: only one, who had a 5.27 mm metastasis with EE, was pN2 following AC.
Conclusions: Extranodal extension is a significant predictor of a positive AC in this group. In its absence, AC did not alter the post-SN biopsy pN stage.