Sentinel Node Biopsy in Ductal Carcinoma in Situ: Is it Justifiable?

Background: For invasive breast cancer, sentinel node biopsy (SNB) is an acceptable alternative to axillary node clearance (ANC), although in the recent era, its role is under review. In ductal carcinoma in situ (DCIS), the benefit of SNB is even less well defined. Despite this, guidelines still recommend that it is performed in selected cases of DCIS. The aim of our study was to evaluate the diagnostic value of performing SNB in DCIS. Methods: Patients with a diagnosis of DCIS who underwent axillary staging with SNB between 2008-2019 in our large volume tertiary centre were identified and included in the study. Results: Out of the 48 patients who were identified, four patients had a positive SNB (8%). Two of those patients were found to have micro metastatic disease. None of the patients with a positive SNB had local or systemic recurrence (median follow up: 40 months). One non-breast cancer-related mortality was reported. Two patients were identified who had recurrent disease, one with an invasive recurrence in the breast, and the other with systemic recurrence in the form of bone disease. Both of these patients had a negative SNB. Conclusion: Our results confirm that performing axillary staging with SNB in DCIS is not justifiable, as it does not affect patient outcomes. This supports the emerging evidence that being more surgically conservative may decrease morbidity without affecting patient survival.