Immunophenotypic Features of CD68 and CD163 Distribution in Oral Squamous Cell Carcinoma of Tongue and Lip

Background and Objectives: Oral squamous cell carcinoma (OSCC) belongs to a broad group of malignant neoplasms of the head and neck. It is known that components of the tumor microenvironment (TME) influence tumor progression. Similar patterns are being actively investigated in OSCC. In particular, a high density of CD68+ macrophages is associated with longer survival, whereas an abundance of M2 macrophages (CD163+) correlates with metastasis and an unfavorable prognosis. The present study compares the density and spatial distribution of CD68+ and CD163+ macrophages between intratumoral and peritumoral compartments in OSCC of the tongue and lip. Materials and Methods: Data from 112 patients with a verified OSCC diagnosis were included in this study. For the comparative morphological analysis, two core groups were formed: (a) Group I (n = 84), patients with Squamous Cell Carcinoma (pT1) of the tongue; (b) Group II (n = 28), patients with Squamous Cell Carcinoma (pT1) of the lip. Immunohistochemistry was performed according to standard protocols. Results: Tongue OSCC was characterized by the predominant accumulation of both CD68+ and CD163+ macrophages in the peritumoral stroma compared with the intratumoral zones (34.2 ± 8.1 vs. 48.1 ± 6.4 cells/mm2). In contrast, in lip OSCC, a higher density of CD68+ macrophages was observed in the intratumoral compartment, whereas the number of CD163+ macrophages remained considerably lower in both the intratumoral (51.1 ± 4.3 vs. 9.4 ± 2.1 cells/mm2) and peritumoral stroma of the tumor. Conclusions: These findings demonstrate that tongue and lip OSCC harbor distinct patterns of macrophage distribution and polarization, underscoring the role of the immune microenvironment in the biological heterogeneity of OSCC and warranting further investigation into macrophage subtype-specific prognostic markers.