Fig. 2

Pathological staining of resected tumor. Histology reveals an abscess containing fungal hyphae surrounded by a collagenous wall. a H&E stain shows the abscess wall containing mixed inflammatory cells, including abundant neutrophils. b Higher magnification is indicated by the white square in a. Hyphae are visible within the abscess wall c Elastica-van-Gieson stain demonstrates the collagenous abscess capsule. d Grocott silver stain illustrates septate hyphae branching at right angles, consistent with aspergillus