Inflammatory pseudotumor of the temporal bone.
OBJECTIVE
To characterize the clinical presentation, imaging characteristics, intraoperative findings, and key histopathologic features of inflammatory pseudotumors of the temporal bone. Findings from an index case are presented, and the literature is reviewed for comparison.


METHODS
Retrospective case review.


METHODS
University tertiary referral center.


METHODS
Cases were identified by review of surgical specimens from the temporal bone and lateral skull base with histopathologic confirmation. A single case was identified at our institution. Nine additional cases were identified in the literature; clinical features were reviewed.


METHODS
Of reported cases, treatment consisted of complete surgical excision in eight cases and subtotal excision in one. The index patient underwent surgical excision with postoperative corticosteroid therapy for adjacent meningeal involvement, after histopathologic interpretation. Corticosteroids were administered to one patient with residual microscopic tumor, and external beam radiotherapy was used for residual/recurrent disease in one case.


RESULTS
The lesions were typically locally aggressive with extensive bony erosion. Three cases (33%) demonstrated labyrinthine and otic capsule involvement. Four cases (44%) involved the facial nerve. Characteristic histopathologic features included fibroblastic proliferation and a mixed inflammatory cell infiltrate in all cases. Mitotic figures, nuclear pleomorphism, and necrosis were rare or nonexistent.


CONCLUSIONS
Inflammatory pseudotumors of the temporal bone are rare but aggressive lesions. Therapy should consist of surgical excision with steroids reserved for residual or intracranial disease or in patients in whom surgery is not an option. These lesions must be differentiated from other infectious, granulomatous, and neoplastic lesions on the basis of histopathologic and immunohistochemical findings.
D003937:Diagnosis, Differential; D004427:Ear Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D004432:Ear, Middle / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D006104:Granuloma, Plasma Cell / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007759:Labyrinth Diseases / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008297:Male; D008416:Mastoid / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D013701:Temporal Bone / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed