Histology of the lachrymal gland and mandibular bone. Fibrous inflammation characteristic of tumefactive fibroinflammatory lesion. (a) Hematoxylin and eosin staining of mandibular bone. Trabeculae were lined by osteoblasts showing active bone remodeling, and intertrabecular spaces were filled with fine fibrous tissue. There was mild lymphocytic infiltration, but no evidence of active osteomyelitis. (b) (c) (d) Hematoxylin and eosin staining of lachrymal gland. (b) Lachrymal glands and ducts were surrounded by sclerotic fibrous stroma (arrow). (c) The lobules are slightly atrophic. Periductal sclerotic fibrosis (arrow) was seen. (d) Lymphocytic aggregate was seen at the periphery of the lobule. (e) (f) Immunohistochemical staining for IgG (e) and IgG4 (f) of lachrymal gland. IgG4-positive cells (arrow) were very few.