Figure 3. Intraoperative cytology by squash preparation of the resected left parietal brain mass is negative for malignant central nervous system tumors.

Extensive neutrophilic infiltration with granulomatous giant cells (arrow) is evident (squash, HE stain x100 and x400). Surgical pathology specimens show acute abscesses and marked necrosis. Fibrotic tissue (arrow), dense fibrinoid necrosis and inflammatory debris (arrowhead), and a substantial neutrophilic infiltration (asterisk) within the brain parenchyma (HE stain, x40). Abscesses containing Langerhans giant cells (arrows), fibrosis, dystrophic calcifications (arrowhead), and a remarkable neutrophilic infiltration (asterisk) at higher magnifications (HE stain, x100 and x400).