P148

Abstract

Tumor-associated macrophages play a main role in tumor progression and dissemination. Taking into account the high heterogeneicity of tumor the different clinical impact of macrophages, infiltrating different sites of tumor, could be expected. The aim was to detect the level of CD68+ cells (macrophages) in the different site of stroma in breast tumor in comparison to clinical course. Materials and methods: One thirty-six women with nonspecific invasive breast cancer T1-4N0-3M0, who were treated in General Oncology Department of Tomsk Cancer Research Institute (Tomsk, Russia), were included in the present study. Patients did not receive preoperative treatment. The material was fixed in 10–12% neutral formalin. Preparation of the histological material was carried out according to standard procedures. Morphological examination of the surgical specimens was performed by the standard method using a light microscope “Carl Zeiss Axio Lab.A1” (Germany) and slidescanner “MiraxMidiZeiss” (Germany). Metastatic lesion was detected in regional lymph nodes. Immunohistochemical study was performed according to standard procedures. Cytoplasmic expression of these markers was determined in the inflammatory cell infiltrate of different tumor segments: (1) in areas with soft fibrous stroma; (2) in areas with coarse fibrous stroma; (3) in the areas of the so-called “maximum stromal-and-parenchymal relationship” where the individual tumor cells, short strands and groups of tumor cells arranged in soft fibrous stroma; (4) among parenchymal elements; (5) in gaps of ductal tumor structures. Double-stained immunofluorescence was performed according to standard procedures using Leica TCS SP2 laser-scanning spectral confocal microscope (Germany). The following primary antibodies were used: mouse monoclonal anti-human CD68 (BD Biosciences) and rabbit polyclonal anti-stabilin-1 or RS1 (marker of M2 macrophages). Results: The highest expression of CD68 in the inflammatory cell infiltrate was detected more frequently in areas with soft fibrous stroma (54%) or the so-called “maximum stromal-and-parenchymal relationship” (79%) in patients with breast cancer. The lowest expression of CD68 was observed in areas with coarse fiber stroma (23%). The CD68-positive cells of the inflammatory infiltrate were located between parenchymal elements of tumor (88%). Inverse correlation (R = −0.67; p = 0.02) observed between tumor size and the expression of CD68 in the cells of the inflammatory infiltrate in gaps of tubular tumor structures. The CD68 expression in cells of the inflammatory tumor infiltrate was correlated with the presence of metastatic regional lymph nodes. It was found that in the case of the lymph node metastases the average score of CD68 expression in cells of ductal gaps tumor structures was lower (1.4 ± 0.5) in comparison with the negative lymph nodes case (3.1 ± 1.0; F = 10.9; p = 0.007). Same time no correlation between the CD68 expression in the inflammatory cell tumor infiltrate and the rate of tumor malignancy was found. Using confocal microscopy domination of CD68+/RS1+ cells were found. Conclusion: So, low CD68 expression level in ductal gaps tumor structures is associated with the presence of metastatic regional lymph nodes.