Frozen Section Evaluation of Methylene Blue Dye based Sentinel Lymph Node Biopsy in Early Breast Cancer – A Feasibility Pilot Study in a Tertiary Cancer Centre
Background: Most of the major cancer centres have adopted sentinel lymph node biopsy (SNLB) as standard means of axillary nodal assessment as an alternative to axillary lymph node dissection (ALND) in clinically node negative early breast cancers. The benefits of SNLB is to reduce the functional disability which is a potential consequence of ALND. A major pitfall of SNLB is the potential of false negative rate which will increase the risk of an axillary recurrence.
Methods: This is a pilot study of forty one cases of clinically N0, T1 and T2 tumors for whom sentinel lymph node mapping was done using methylene blue dye to detect occult metastasis. This was validated by complete ALND in all cases.
Results: The calculated accuracy of the frozen section analysis was 97.5%, sensitivity was 85.7% and specificity was 100%. Positive predictive value was100%, negative predictive value was 97.14% and false negative rate was 2.86%
Discussion & Conclusion: This study demonstrates a high sensitivity and specificity for frozen sections of SNLB with an accuracy of 96%.