Role of Lymphoscintigraphy in Repeat Sentinel Lymph Node Biopsy for cN0 Ipsilateral Breast Cancer Recurrence.

In patients with ipsilateral breast tumor recurrence (IBTR), lymphatic drainage may be altered due to factors such as prior axillary surgery and radiotherapy, thereby increasing the likelihood of sentinel lymph nodes (SLNs) in atypical locations. This study aimed to evaluate patients who underwent surgery for IBTR with lymphoscintigraphy for repeat SLN biopsy (re-SLNB), and to investigate the role of lymphoscintigraphy in re-SLNB in this patient group. Patients diagnosed with IBTR who were evaluated using preoperative lymphoscintigraphy and subsequently underwent surgery were included in the study. Patients with systemic or nodal metastases, as well as those who did not undergo lymphoscintigraphy, were excluded. Demographic, clinical, and pathological data of the included patients were analyzed. A total of 16 patients were evaluated, with a median age of 56 years (range 30-73), all of whom were female. Lymphoscintigraphy successfully localized the SLN in 81.3% of the patients. In eight patients, the SLN was located in the ipsilateral axilla, while in five patients, it was found in the contralateral axilla. Axillary lymph node dissection (ALND) was performed in three patients (all in the contralateral axilla) due to metastatic involvement in the SLN. ALND during first surgery was associated with an increased likelihood of SLN detection in the contralateral axilla or Re-SLNB failure (p=0.043). In patients undergoing surgery for IBTR, the likelihood of the SLN being in atypical locations is high. Lymphoscintigraphy may enhance the success of Re--SLNB in this patient group.