Sentinel node mapping and ductal carcinoma in situ

Pure ductal carcinoma in situ (DCIS) is typically unassociated with a risk of regional lymph node involvement. Retrospective series maintain that larger tumors or high-grade histopathology may harbor a risk of lymph node involvement.

Our community hospital retrospectively reviewed a series wherein women with DCIS were subjected to sentinel lymph node biopsy based on large tumor size and/or high-grade histopathology.

232 consecutive women with a diagnosis of pure DCIS were evaluated independently by two breast surgeons, one who typically offers sentinel node mapping to patients with tumors larger than 10 mm and the other who offers sentinel node mapping to women with grade 3 tumors. 60 women (26%) underwent sentinel node mapping along with appropriate surgery directed to the breast. Women were offered risk-adjusted adjuvant radiotherapy and anti-endocrine therapy.

At a median follow-up of 18 months (range 6-132 months), 9 women (15%) were identified with regional axillary nodal disease. A statistical analysis was conducted between women who did or did not undergo sentinel node mapping because there was overlap in large tumor size and high grade between the two groups. A univariate logistic regression statistic showed a trend toward a significant relationship between grade 3 tumors and a risk of occult nodal involvement. This was not confirmed by multivariate analysis.

In our moderate-sized surgical experience evaluating women with pure DCIS who underwent a sentinel node mapping due to large tumor size or high grade histology, we were unable to confirm that either is predictive of occult node involvement.