Background and objectives: A failure to visualize axillary sentinel nodes in lymphoscintigraphy may lead to an unsuccessful sentinel node biopsy (SNB) and subsequent axillary lymph node dissection (ALND). To avoid unnecessary ALND, a second radioisotope injection may be given but has been considered hazardous. We investigated the axillary recurrence rate after tumor-negative SNB in breast cancer patients who received a second tracer injection after axillary visualization failure in lymphoscintigraphy.
Methods: Altogether 1,309 breast cancer patients who underwent a tumor-negative SNB without an ALND were included. Two hundred seven (15.8%) patients received a second tracer injection due to visualization failure in lymphoscintigraphy and 1,102 (84.2%) did not. All patients received a blue dye injection prior to the SNB. The median follow-up time was 43 months.
Results: No isolated cancer recurrences were diagnosed in the ipsilateral axilla among patients who received two radioisotope injections. Disease-free survival and overall survival were similar among patients with one or two radioisotope injections (P = 0.122 and P = 0.200, respectively).
Conclusions: Additional radiocolloid tracer injection after axillary non-visualization in lymphoscintigraphy is safe and does not increase axillary recurrence risk after tumor-negative SNB. The results suggest that such patients can be safely managed with SNB without a need to perform an ALND.