Related Experiment Video
Updated: Dec 9, 2025
The Application of 1% Methylene Blue Dye As a Single Technique in Breast Cancer Sentinel Node Biopsy
Published on: June 1, 2019
Flow Cytometry for Detection and Quantification of Micrometastases in Sentinel Lymph Nodes from Patients with Primary
Luisa Hellmich1, Kai-Erik Witte2, Martin Ebinger2
1Department of Dermatology, University of Tuebingen, Tuebingen, Germany; Department of Dermatology, University of Cologne, Cologne, Germany.
Background:
Detection of micrometastases in the regional lymph nodes is one of the most important prognostic factors for melanoma patients. Our aim was to evaluate the suitability of flow cytometry for rapid quantification of disseminated melanoma cells in sentinel lymph nodes (SLN).
Methods:
132 SLNs from 104 patients diagnosed with melanoma were analyzed by flow cytometry, utilizing the extracellular marker melanoma-associated chondroitin sulfate proteoglycan, in addition to quantitative immunocytology and conventional histopathology, including immunohistochemistry. For quantification, the number of melanoma-positive cells per million lymph node cells (disseminated cancer cell density, DCCD) detected by flow cytometry was compared to the DCCD obtained by immunocytology.
Results:
Compared to histopathology and immunocytology, flow cytometry exhibited a sensitivity of 50% and a specificity of 85%. DCCDs of immunocytology and flow cytometry of the 37 immunocytologically positive SLNs showed a positive correlation (Spearman's ρ = 0.7, P < 0.0001). In 10 SLNs from 9 patients with high tumor load, the flow cytometric DCCD was 8-fold higher on average than the immunocytologic DCCD.
Conclusions:
Although flow cytometry is not yet suitable for early detection of metastatic melanoma, it promises to become a valuable tool for rapidly quantifying tumor load in high-risk patients.
