Quantitative Assessment of Tumor Associated Macrophages in Head and Neck Squamous Cell Carcinoma Using CD68 Marker: An Immunohistochemical Study.

Abstract

Oral Squamous Cell Carcinoma (OSCC) is one of the most prevalent cancers in India. Clear evidence regarding inflammation being an etiological factor of cancer was found only in the last few decades. A major inflammatory component in the tumor tissue is Tumor-Associated Macrophages (TAMs). The CD68 antibody is a marker for staining TAMs. The aim of this study is to quantify the macrophage count in healthy oral mucosa and OSCC and comparing TAMs in different histopathological grades of OSCC immunohistochemically. Thirty archival specimens of OSCC patients and 10 healthy biopsy samples were collected. Immunohistochemical staining was done using a CD68 marker. Statistical analysis was done using Kruskal-Wallis ANOVA and Mann-Whitney U test. Comparing CD68 expression in various study groups showed a significant difference (p=0.000). The pair-wise analysis showed different grades of OSCC, which differed significantly for CD68 expression from the normal oral mucosa. The most significant cells present in tumor stroma are TAMs, which remain in close proximity to neoplastic cells and interact with them via several chemical mediators, which may serve to increase the invasiveness of the malignant epithelium. Dense infiltration of TAMs adjacent to tumor cells and islands vividly implies their role in tumor progression.