Abstract Aim Ductal carcinoma in situ (DCIS) is a non-invasive breast cancer precursor, confined to the ducts, with a very low risk of lymph node metastasis (1%). The NICE guidelines recommend sentinel lymph node biopsy (SLNB) for patients undergoing mastectomy for DCIS to detect occult invasive disease. For breast-conserving surgery (BCS), SLNB is considered in high-risk patients, such as those with extensive microcalcifications, a palpable mass, or mass-like lesions, due to the added morbidity and resource use of SLNB. Method Data were prospectively collected from patients undergoing BCS or mastectomy for DCIS at a single unit between 2017 and 2022. Parameters included pre-operative tumor size, histological grade, type of surgery, and postoperative tumor size and histology, with SLNB data recorded where applicable. Results Eighty-five patients underwent WLE and 17 mastectomy. Mean age was 62 years in both groups. Four high-risk BCS patients underwent upfront SLNB; one had microinvasion. Of the 81 BCS patients without upfront SLNB, three developed invasive disease and underwent SLNB as a second procedure. The odds ratio for upfront SLNB in high-risk patients was 8.66 (95% CI: 0.68–109.9, p=0.0956), indicating higher likelihood of invasive disease postoperatively, though not statistically significant, due to small sample size. Conclusions This audit supports selective SLNB for high-risk patients undergoing BCS. While the high-risk group was more likely to have invasive disease, the result was not statistically significant due to the small sample size. Further studies are needed to refine SLNB indications in DCIS.
Oskui et al. (Fri,) studied this question.