With DCIS incidence on the rise, up to 30

PURPOSE:Recent studies have established the safety and efficacy of Superparamagnetic Iron Oxide (SPIO, Magtrace®) for delayed sentinel lymph node biopsy (SLNB) in patients with ductal carcinoma in situ (DCIS) who are undergoing mastectomy. The aim of our study was to measure cost containment with use of Magtrace® in comparison to upfront SLNB with traditional technetium-99 lymphatic tracer. METHODS:A total of 41 patients at our institution underwent mastectomy with Magtrace® injection for DCIS and were included in our single-institution, retrospective analysis. For comparison, total charges data were obtained for an upfront SLNB at the time of mastectomy. Cost comparison analysis was then performed against charges for intraoperative Magtrace® injection with additional charges incorporated for those patients who required return to the operating room for delayed SLNB. Total cost containment for the cohort with use of Magtrace® was then measured. RESULTS:Of the 41 patients who underwent Magtrace® injection, two patients required return to the operating room for a delayed SLNB for invasive disease. Including these charges for a second encounter into our cost analysis, the use of Magtrace® still yielded an overall cost containment of $205,793.55 in our cohort when comparing to patients who underwent upfront SLNB. For patients who underwent Magtrace® injection and did not require return to the operating room, charges were reduced by $6,768.52 per patient. CONCLUSION:The use of Magtrace® for delayed SLNB in patients with DCIS undergoing mastectomy yielded a significant overall cost containment, further supporting its use in this patient population.

Purpose Unnecessary axillary surgery can potentially be avoided in patients with DCIS undergoing mastectomy. Current guidelines recommend upfront sentinel lymph node biopsy during the index operation due to the potential of upstaging to invasive cancer. This study reviews a single institution’s experience with de-escalating axillary surgery using superparamagnetic iron oxide dye for axillary mapping in patients undergoing mastectomy for DCIS. Methods This is a retrospective single-institution cross-sectional study. All medical records of patients who underwent mastectomy for a diagnosis of DCIS from August 2021 to January 2023 were reviewed and patients who had SPIO injected at the time of the index mastectomy were included in the study. Descriptive statistics of demographics, clinical information, pathology results, and interval sentinel lymph node biopsy were performed. Results A total of 41 participants underwent 45 mastectomies for DCIS. The median age of the participants was 58 years (IQR=17; range 25 to 76 years), and the majority of participants were female (97.8%). The most common indication for mastectomy was diffuse extent of disease (31.7%). On final pathology, 75.6% (34/45) of mastectomy specimens had DCIS without any type of invasion and 15.6% (7/45) had invasive cancer. Of the 7 cases with upgrade to invasive disease, 2 (28.6%) of them underwent interval sentinel lymph node biopsy. All Sentinel lymph nodes biopsied were negative for cancer. Conclusion The use of superparamagnetic iron oxide dye can prevent unnecessary axillary surgery in patients with DCIS undergoing mastectomy.