Invasive Breast Carcinoma with Abundant Collagenous Stroma Shows Lower Level of CD68-Positive Tumor Associated Macrophages than Those of Invasive Carcinoma without Abundant Collagenous Stroma

BACKGROUND AND AIM OF THE WORK: The significance of association between cancer and its stromal microenvironment has been recognized. We aimed to investigate the immunohistochemical staining features of D2-40 (podoplanin), SMA (smooth muscle actin) and CD68 (pan-macrophage marker) in patients with early stage invasive breast cancer with/out peritumoral PASH-like stroma. METHODS: The H&E sections of core needle biopsy specimens of invasive breast carcinomas diagnosed during one-year time period were reviewed in terms of the presence of accompanying PASH-like stroma retrospectively. Cases with similar pattern of growth in their surgical excision materials were included. Eight cases were grouped as ‘Invasive tumor with PASH-like stroma’ and 21 cases as ‘Invasive tumor without PASH-like stroma’, consecutively. The results of immunohistochemical staining for D2-40, SMA and CD68 were noted semiquantitatively as ‘negative’,’weak’, moderate’ or ‘strong’. RESULTS: CD68 was found significantly lower in invasive tumor with peritumoral PASH-like stroma than those of tumor without PASH-like stroma. No significant differences were found for SMA and D2-40 between two groups. CONCLUSIONS: Tumor-associated macrophages (CD68 positive) in tumor stroma have been demonstrated in association with tumor behavior in several studies. The presence of peritumoral PASH-like stroma, which is poorly staining for CD68, might be a morphological clue for the behavior of tumor. (www.actabiomedica.it)