Sentinel node mapping and ductal carcinoma in situ.

Area of Science:

• Oncology
• Surgical Pathology
• Breast Cancer Research

Background:

• Pure ductal carcinoma in situ (DCIS) is generally considered low-risk for lymph node metastasis.
• Previous studies suggested larger tumors or high-grade histopathology might increase the risk of regional lymph node involvement in DCIS.

Purpose of the Study:

• To retrospectively evaluate the predictive value of large tumor size and high-grade histopathology for sentinel lymph node metastasis in patients with pure DCIS.
• To assess the outcomes of sentinel lymph node biopsy in a community hospital setting for selected DCIS cases.

Main Methods:

• A review of 232 women diagnosed with pure DCIS was conducted.
• Sentinel lymph node biopsy was performed based on criteria of tumor size (>10 mm) or grade 3 histopathology.
• Statistical analysis, including univariate and multivariate logistic regression, was used to assess the relationship between tumor characteristics and nodal involvement.

Main Results:

• Of 60 women who underwent sentinel node mapping, 9 (15%) had regional axillary nodal disease.
• Univariate analysis showed a trend towards a significant association between grade 3 tumors and occult nodal involvement.
• Multivariate analysis did not confirm this association, indicating neither large size nor high grade reliably predicted nodal metastasis.

Conclusions:

• In this cohort of women with pure DCIS undergoing sentinel lymph node mapping due to tumor size or grade, neither factor was found to be a significant predictor of occult lymph node involvement.
• The findings suggest that current criteria for selecting DCIS patients for sentinel node biopsy may not be optimal for identifying those at risk of nodal metastasis.