Sentinel lymph node biopsy in multicentric breast cancer: five-year results in a large series from a single institution.

PURPOSE: This study was designed to present the 5-year results of patients with multicentric breast cancer who underwent sentinel lymph node biopsy (SLNB) in a single institution.

METHODS: Between June 1999 and December 2007, 337 patients with multicentric breast cancer and a clinically negative axilla underwent lymphatic mapping by a single periareolar/peritumoral (n = 306) or a double peritumoral or subdermal injection (n = 31) of (99m)Tc-HSA nanocolloids. The sentinel lymph node (SLN) was evaluated by intraoperative frozen section and axillary dissection was performed only in cases of positive SLNB.

RESULTS: The median age of the patients was 48 (range, 22-81) years. The mean number of hot spots identified was 1.4 in the whole series, 1.3 in patients who received a single injection, and 1.7 in those who received a double injection (P < 0.001). The mean number of removed SLNs was 1.7 (median, 1; range, 1-7) with an identification rate of 100%. A total of 138 patients with negative SLNB (n = 134) or isolated tumor cells in the SLN (n = 4) did not receive completion axillary lymph node dissection (CALND). In these latter patients, a total of 27 events (19.5%) occurred with 3 patients (2.2%) developing axillary recurrences after a median follow-up of 5 years (range, 17-134 months).

CONCLUSIONS: Axillary lymph node reappearance was infrequent among patients with multicentric breast cancer, having negative SLNB and no CALND. We recommend SLNB as the standard procedure for nodal staging in patients with multicentric breast cancer and a clinically negative axilla.