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Updated: Jun 21, 2025

Surgical Treatment of an Endolymphatic Sac Tumor
Published on: May 26, 2023
Nonspecific inflammatory pseudotumor of the maxillary and temporal fossa: a study of seven cases
Wataru Kakuguchi1, Yuichi Ashikaga1, Yasuhito Moritani2
1Department of Oral and Maxillofacial Surgery, Division of Oral Pathobiological Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University, Sapporo, Japan.
Objective:
Inflammatory pseudotumor (IPT) is a rare, locally aggressive, benign neoplasm of unknown etiology. Because of its aggressive clinical behavior and locally destructive or infiltrative features, it may be mistaken for a malignant tumor. Approximately 5%-44% of extrapulmonary IPT occur in the head and neck, primarily affecting the orbit.
Study Design:
Between 2008 and 2021, our hospital received referrals for seven patients (three men and four women, aged 42-73 years) with pain, swelling, mass, and trismus. Computed tomography, magnetic resonance imaging, and biopsy were performed on all patients to diagnose IPT.
Results:
Of the seven patients, four received low-dose prednisolone (PSL), one underwent surgery, and two were left untreated. The IPT disappeared in one of the two untreated cases, whereas it improved and later deteriorated in the other. The surgical patient had no recurrence. Low-dose PSL was effective in two patients; however, high-dose PSL and immunosuppressants were required in the remaining two cases owing to infiltration into each orbit or brain region.
Conclusions:
Low-dose PSL treatment was applicable in IPT cases affecting the maxillary to temporal fossa region, wherein symptoms did not improve without treatment. However, when low-dose PSL was ineffective, high-dose PSL and immunosuppressants were required.

