[Feasibility of the sentinel node biopsy in breast cancer in case of histological multifocality diagnosis]

The use of sentinel node biopsy (SNB) has replaced axillary lymph node dissection (ALND) as the new standard of care in early unifocal breast cancer. In multifocal breast cancer, this procedure remains controversial. The real problem is when a multifocal tumor is discovered during or after the surgery, with a SNB negative which has been already done. Should we do an additional ALND or not?We performed a retrospective study of 43 multifocal breast cancer patients who underwent SNB.The mean histological primary tumor size was 16.8 mm (range, 1-52 mm). The mean number of SN removed was 2.07 (range, 1 to 5). Sixteen (34.1%) of the 43 patients had at least one positive SN. Twenty-seven patients had subsequent axillary dissection. Negative predictive value of SN procedure was 100% (95% confidence interval: 87.1-100%) with a FN rate of 0%. Moreover, not any patient has developed axillary recurrence with a mean follow-up of 20.8 months (1-77).Our data are not powerful enough to validate the SNB in multifocal breast tumor discovered after an initial surgery. However, the FN rate of 0% is encouraging and prospective studies with a systematic ALND can help surgeons to respond to the question.