Scanning electron microscopy of exudative macrophages in malignant lymphoma.

The possible value of scanning electron microscopy (SEM) of skin window preparations in the clinical situation has been investigated with reference to 48-hour macrophages in 26 patients with malignant lymphoma. The preparations were processed for SEM using critical point drying and sputter coating. Identification of macrophages was made with reference to light microscopy both of parallel preparations and of specimens already studied by SEM. Distinctive SEM appearances were present in most of the patients. Although many macrophages were similar to those from normal subjects, the majority showed a more variable morphology including the presence of ruffles and coarse ridge-like profiles. Highly significant differences were found on statistical analysis. It is suggested that immaturity of the 48-hour macrophages is present in some patients with malignant lymphoma (perhaps reflecting the macrophage dysfunction already described in these diseases). The findings indicate the potential clinical application for this technique.