Peri and intratumoral macrophage infiltration in laryngeal carcinoma. An immunohistochemical study

The role of macrophages infiltrating tumor tissue is still poorly explained; the data available are sparse and, to the best of our knowledge, there is no study relating the characteristics of such infiltration to tumor evolution and final outcome. We decided to investigate the spatial relationships between macrophages and neoplastic tissue and their possible prognostic significance on a series of laryngeal carcinomas (98 patients) all of which were operated in our Department and had a follow-up of at least 3 years. In order to identify the macrophage infiltration, formaline-fixed/paraffin-mounted specimens of the tumor were treated with MoAb HAM56. No statistically significant relationship could be established between the degree of macrophage infiltration and the clinical outcome (recurrence), even when the N status was taken into account (N- vs. N+). However, a clear trend was observed when the analysis was confined to grade 3 cases, where the presence of a significant number of macrophages was correlated with a higher probability of recurrence.