Influence of preoperative breast cancer localization techniques on rates of sentinel lymph node visualization with preoperative lymphoscintigraphy

Objectives The use of preoperative image-guided lesion localization for impalpable breast cancer may interfere with lymphatic drainage and cause delayed or reduced visualization of sentinel lymph nodes (SLNs) on preoperative lymphoscintigraphy. The goal of this audit was to compare rates of SLN visualization in patients undergoing preoperative breast cancer localization with either Iodine 125 seeds (radio-guided occult lesion localization using Iodine 125 seeds, ROLLIS) or hook wire and those with palpable lesions where no localization was required. Patients and methods We reviewed the records of 482 patients, who underwent preoperative lymphoscintigraphy with hook wire, ROLLIS, or no localization, at three major tertiary hospitals from January 2013 to December 2017. Static lymphoscintigraphy images are performed post administration of subcutaneous periareolar(99m)Tc antimony colloid injection. The rate of SLN visualization in the three groups and time to node visualization were analyzed. Results Four hundred and eighty-two patients underwent preoperative lymphoscintigraphy: 102 after no localization, 211 in hook wire, and 169 following ROLLIS. Very high overall rates of SLN visualization on preoperative lymphoscintigraphy were noted in all three groups; no localization group: 99% [95% confidence interval (CI), 94.7-99.8%], hook wire: 98.6% (95% CI, 95.9-99.7%) and ROLLIS: 98.8% (95% CI, 95.8-99.9%). For time to node visualization, a statistically significant difference was found between the no localization versus hook-wire group (P = 0.0015) and no localization versus ROLLIS group (P = 0.00011) but no statistically significant difference between the hook-wire and ROLLIS groups (P = 0.16) was demonstrated. Conclusion High rates of SLN visualization on preoperative lymphoscintigraphy were noted in all groups, with no significant reduction when breast lesion localization techniques were used. There was; however, an increased rate of delayed imaging required for SLN visualization in women who had undergone either type of preoperative localization compared with those who had not.