Inflammatory Pseudotumor of the Petrous Apex With Spontaneous Improvement of the Lesion

Inflammatory myofibroblastic disease of right petrous apex: A rare case with review of literature

ABSTRACT

Inflammatory myofibroblastic tumor (IMFT) is a rare tumor of unknown etiology. It can involve any part of the body. The IMFT involving the base of skull is rare with only 36 cases reported in the literature. We report a rare case of IMFT of temporal bone with review of literature. A 42 year old male presented with complaints of headache and double vision and MRI brain showed lesion in the right petrous apex region suggestive of a neurogenic mass. He had excision of lesion and histopathology was suggestive of IMFT with IgG4 and ALK positive. He had complete clinical response but a month later he presented with right eyelid ptosis and decreased rotation of eye medially with recurrent lesion on MRI. Patient received radiation by SRT technique and then started on Ceretinib with partial response. The IMFT is rare tumor of unknown etiology and tumors of temporal bone are more aggressive. It is benign but locally invasive tumor. Treatment of IMFT is controversial. Extensive surgery with complete excision has about 80% response rates and with intracranial extension, adjuvant radiation is need. In head and neck IMFT response rates are lower (30 to 40%). Monoclonal antibodies and steroids are used in IMFT at recurrence. In advanced or metastatic ALK positive tumors, Crizotinib is used with a response rate of 50%. Radiotherapy (25 to 30 Gy) induces remission and helps to taper the steroids. Temporal bone IMFT is a rare tumor with multimodality approach and variable response to treatment.

Labyrinthine destruction caused by inflammatory pseudotumor of the temporal bone: A report of three cases and review of the literature

BACKGROUND

Inflammatory pseudotumors (IPTs) are rare, idiopathic, and inflammatory lesions that are histopathologically benign. Here, we present three cases of labyrinthine destruction caused by an IPT.

METHODS

The first patient was a 74-year-old male with a mass lesion extending from the inner ear to the external ear canal. The second patient was a 62-year-old female with a foliated polycystic lesion in the petrous bone on the dorsal side of the left internal auditory canal. The third patient was a 68-year-old female with a mass extending from the inner ear to the middle ear, destroying the semicircular canal and cochlea.

RESULTS

In two cases, we performed surgical resection successfully with no recurrence. In the other case, the lesion showed shrinkage after chemotherapy for colorectal cancer incidentally found during the examination process.

CONCLUSION

Surgical technique and indication for IPT should be based on the location and function of the lesion. In addition, there is room to consider pharmacotherapy as a treatment option for IPT of the temporal bone.

LEVEL OF EVIDENCE

4.

Inflammatory Pseudotumor of the Temporal Bone: A Case Series

OBJECTIVE

Inflammatory pseudotumor of the temporal bone is a benign, idiopathic inflammatory process that is locally invasive and a cause of significant morbidity. This study reviews our experience with seven patients and is currently the largest series to date.

STUDY DESIGN

Retrospective review from January 1, 2014 to January 1, 2016.

SETTING

Single tertiary medical center.

PATIENTS

There were five male and two female (n = 7) subjects with a diagnosis of temporal bone inflammatory pseudotumor. The mean age at presentation was 41 years old. The most common presenting symptoms were hearing loss (7/7) and headache (4/7). Four patients demonstrated an inflammatory aural polyp. Two patients experienced facial nerve paralysis.

INTERVENTION(S)

Seven patients underwent computed tomography and six underwent magnetic resonance imaging. Corticosteroids and antibiotics were the initial treatment of choice. Five patients also underwent surgery. As adjuvant therapy, two patients received Rituximab, one patient received radiation, and one received mycophenolate mofetil.

MAIN OUTCOME MEASURE(S)

Clinical courses were followed with focus on symptoms, disease recurrence, duration, and treatment. Mean follow-up was 17.8 months.

RESULTS

The primary lesions demonstrated T2 hypo-intensity and enhancement as well as diffuse dural thickening on magnetic resonance imaging in five of six patients. Histopathology demonstrated chronic inflammation in the setting of hyalinized fibrosis (7/7). All the patients are currently symptomatically stable.

CONCLUSION

Inflammatory pseudotumor of the temporal bone can cause devastating effects on neurological function and quality of life. Recognition of characteristic imaging and histopathology can expedite appropriate treatment. Patients may require chronic steroid therapy. Adjunctive therapy with radiation and immuno-modulation are currently being explored.

Sinonasal and ventral skull base inflammatory pseudotumor: a systematic review

OBJECTIVES/HYPOTHESIS

Inflammatory pseudotumor is a benign idiopathic inflammatory process often misdiagnosed as an infection or neoplasm. This review analyzes all reported cases of sinonasal and ventral skull base inflammatory pseudotumor to date, and provides a framework for evaluation and management of this uncommon condition.

DATA SOURCES

MEDLINE/PubMed database.

REVIEW METHODS

A search for articles related to sinonasal and ventral skull base inflammatory pseudotumor, along with bibliographies of those articles, was performed. Demographics, presentation, radiographic findings, treatment, follow-up, and outcome were analyzed.

RESULTS

Thirty-three articles were reviewed, including a total of 87 patients. The most common presenting symptom was vision change (58.6%). Sinonasal and ventral skull base inflammatory pseudotumor was found in the cavernous sinus in 46.0% of cases. The lesion appeared isointense (66.7% of cases) and homogeneously enhancing on T1-weighted magnetic resonance imaging (MRI), whereas it appeared hypointense on T2-weighted MRI in 90.7% of cases. Inflammatory pseudotumor appeared hyperdense on computed tomography in 78.9% of cases. Histopathological analysis of biopsied specimens revealed presence of inflammatory cells (94.4%) and fibrosis (80.3%). Corticosteroids alone were the most common treatment modality (55.2%), resulting in disease-free patients in 22.9% of cases over a median follow-up period of 17.6 months. Surgical management alone was uncommon (8.0%), but showed high success rate (57.1%).

CONCLUSION

This review is the most comprehensive analysis of sinonasal and ventral skull base inflammatory pseudotumor to date. Radiologic findings and histopathological analysis are essential for diagnosis. Corticosteroids are the most common treatment modality. Surgery, although uncommon, appears to be an efficacious treatment modality.

Inflammatory pseudotumor of the temporal bone: three cases and a review of the literature

Inflammatory pseudotumor (IP) is a clinically aggressive but histologically benign condition of unknown cause. Its appearance in the temporal bone is uncommon. We present clinical, radiological, and histopathologic findings of three cases originating in the temporal bone. In the first case, a simultaneous IP of the temporal bone and parotid gland was found with histopathologic confirmation. In the second case, an enlarged cervical node, which was also believed to be related to IP, was observed accompanied with the temporal lesion. While the third case presented with chronic suppurative otitis media. Two of them were treated by surgery alone with complete resolve of the diseases. Another one underwent tympanomastoidectomy in combination with oral steroids, radiation, and chemotherapy, but the IP still recurred. A comprehensive review of the literature on clinical features of the temporal pseudotumor was conducted.

Lesions of the petrous apex: classification and findings at CT and MR imaging

The petrous apex is a complex region of the central skull base that is surrounded by a number of important vascular and neural structures and can be home to a wide range of disease processes. Lesions arising in or spreading to the petrous apex cause varied and occasionally severe clinical sequelae, which typically result from mass effect or direct invasion of the cranial nerves, brainstem, or internal carotid artery. Because the petrous apex is not amenable to direct examination, cross-sectional imaging with computed tomography and magnetic resonance (MR) imaging plays an important role in diagnosis and characterization of lesions occurring there. Petrous apex lesions can be classified on the basis of their origin into the following categories: developmental lesions, inflammatory lesions, benign tumors, malignant tumors, vascular lesions, and osseous dysplasias. The most common lesions arising in the petrous apex are cholesterol granulomas, which can be reliably diagnosed with MR imaging due to their high signal intensity on both T1-weighted images and T2-weighted images. In addition, one should also be familiar with anatomic variants or pseudolesions in the petrous apex that can be mistaken for pathologic conditions.

Inflammatory pseudotumor (plasma cell granuloma) of the temporal bone

We report the case of a 41-year-old man who presented with progressive right-sided ear pressure, otalgia, hearing loss, tinnitus, and intermittent otorrhea. Computed tomography and magnetic resonance imaging detected a soft-tissue mass in the right mastoid with intracranial invasion and erosion through the tegmen tympani and mastoid cortex. Histopathologic examination was consistent with an inflammatory pseudotumor (plasma cell granuloma). These lesions rarely occur in the temporal bone. When they do, they are locally destructive and can erode bone and soft tissues. Aggressive surgery is recommended as a first-line treatment, with adjunctive steroid or radiotherapy reserved for residual or refractory disease. Our patient subsequently experienced multiple recurrences, and his treatment required all of these modalities. At the most recent follow-up, he was disease-free and doing well.