Management of sentinel node re-mapping in patients who have second or recurrent breast cancer and had previous axillary procedures

BACKGROUND In patients with recurrent or second primary ipsilateral breast cancer, axillary staging is the key factor in locoregional control and a strong prognostic characteristic. The efficient evaluation of lymphatic drainage of re-sentinel lymph node biopsies (re-SLNBs) has remained a challenge in the management of ipsilateral primary or recurrent breast cancer patients who are clinically lymph node negative. This study explores whether a SLNB for patients with primary or recurrent breast cancer is possible after previous axillary surgery. It evaluates potential reasons for mapping failure that might be associated with patients in this group. METHODS Between March 2006 and November 2013, 458 patients were subjected to a breast SLNB. A lymphoscintigraphy procedure was performed on 330 patients for sentinel lymph node (SLN) mapping on the day of surgery. Seven patients with either a second primary cancer in the same breast or recurrent breast cancer were described. Two of these seven patients had axillary lymph node dissection (ALND) during previous treatments and five had SLNB. A dual mapping method was used for all patients. Preoperative lymphoscintigraphy was performed four hours before surgery. RESULTS SLNs were successfully remapped in six of seven (85.7%) patients, of whom five (71.43%) had previously undergone SLNB and two (28.57%) previous ALND. Localizations of SLNs were ipsilateral axillary in three patients, ipsilateral internal mammary in one patient, and contralateral axillary in two patients. An altered distribution of lymph nodes was discovered in both patients with previous ALND. In one of the two patients, metastases were found in an aberrant lymph drainage basin at the location of a non-ipsilateral axillary node (contralateral axillary SLN). The second previously ALND patient had an internal mammary SLN. In one patient, mapping was unsuccessful and the SLN was not identified. CONCLUSIONS Altered lymphatic drainage incidence increases following breast-conserving surgery for an initial breast cancer, and the location of SLNs becomes unpredictable at the time of a second primary or recurrent ipsilateral breast cancer. This leads to the necessity of using a radionuclide (lymphoscintigraphy) for a successful re-mapping procedure. A re-SLNB is precise and beneficial even though there are few patients. A lymphoscintigraphy can identify SLNs at their new unpredicted location.