Lymphatic mapping after previous breast surgery

BackgroundTo assess the feasibility of lymphatic mapping and determine the lymphatic drainage pathways in patients previously treated with breast conserving therapy (BCT).MethodsWe included patients without current breast cancer that previously received BCT with sentinel node biopsy (SNB) and/or axillary lymph node dissection (ALND) for primary breast cancer. The study population consisted of 44 patients and was divided into two groups according to previous surgical treatment of the axilla: 22 patients after previous SNB and 22 patients after previous ALND. Standard lymphatic mapping was performed and the lymphatic drainage pattern was registered. Drainage located outside the ipsilateral axilla was recorded as aberrant.ResultsLymphoscintigraphy revealed a drainage pattern in 17 of 44 patients (39%). The identification rate in the SNB-group was 41% and 36% in the ALND-group (P = 0.760). 8 patients (18%) showed aberrant drainage, which tended to be more frequent in the ALND-group than in the SNB-group (27% versus 9%, P = 0.122). Lymphatic drainage to the contralateral axilla was observed in 2 patients, both previously treated with ALND.ConclusionsLymphatic mapping seems feasible after previous BCT with axillary treatment, in spite of a relatively low identification rate. Aberrant drainage tends to be more frequent after previous treatment with ALND.