Inflammatory pseudotumor involving the skull base: response to steroid and radiation therapy

Inflammatory pseudotumor, the great mimicker: A case report

Inflammatory pseudotumor is a rare lesion, especially at the level of the central nervous system. Its etiology is unknown and the most accepted hypothesis is that it is the consequence of an exaggerated immune response. We present the clinical case of a young Senegalese male, with a history of epilepsy secondary to severe cranioencephalic trauma in childhood, who presented with new epileptic seizures. Imaging tests showed a lesion in the anterior fossa intimately attached to the meninges, so the initial diagnosis was meningioma. A bifrontal craniotomy and microsurgical excision were performed. The definitive anatomopathological analysis concluded that the lesion is an inflammatory pseudotumor whose origin is secondary to a disproportionate reparative process after cranioencephalic trauma.

Diagnosis and Treatment of Inflammatory Pseudotumor with Lower Cranial Nerve Neuropathy by Endoscopic Endonasal Approach: A Systematic Review

Inflammatory pseudotumor (IPT) is a non-neoplastic condition of unknown etiology. IPT with lower cranial nerve (CN IX, X, XI, XII) neuropathies is extremely rare. In this study, we systematically reviewed all previously reported cases regarding the management of IPT with lower cranial nerve neuropathies. We searched the PubMed/MEDLINE database for reports related to IPT with lower cranial nerve neuropathies. A total of six papers with 10 cases met the inclusion criteria (mean age 51.6 years, 70% male). The mean follow-up period was 15.4 months (range: 1–60 months). The most frequent treatment was corticosteroids alone (60%), followed by surgery alone (20%), and multimodal treatment (20%). Corticosteroid therapy was associated with an excellent (100%) response rate at 6 months of follow-up, and half of the patients were in complete remission after 9 months. Both cases who received surgery had persistent neurological deficits. Immediate complete remission of neurological symptoms and resolution on imaging after decompression surgery via an endoscopic endonasal approach (EEA) with corticosteroids was demonstrated in our representative case. This review suggests that EEA is a preferred method for diagnosis and treatment, a promising approach associated with favorable outcomes, and a viable first-line treatment for selected cases, followed by multimodal therapy.

Inflammatory pseudotumor simulating a jugular foramen meningioma: case report, technical video and literature review

Inflammatory pseudotumor (IP) is a non-neoplastic, reactive inflammatory process, of unknown etiology, characterized by a proliferation of connective tissue with an inflammatory infiltrate, most commonly involving the lungs and orbits. Primary intracranial inflammatory pseudotumor is an extremely rare entity often arising from the meningeal structures of the skull base. We reported an extremely rare case of a primary intracranial IP located in the cerebello-pontine angle, mimicking a jugular foramen meningioma. We further illustrated our microsurgical technique through a surgical video and performed a review of the pertinent scientific literature. The patient underwent gross total microsurgical resection of the tumor mass through a left retrosigmoid approach. Intraoperative neuro-monitoring of VII-VIII cranial nerve complex and lower cranial nerve was performed, and thulium laser fibers were used as a tool for tumor debulking. Post-operatively, patient neurological symptoms recovered. Histopathological studies showed dense infiltrate of T and B cells lymphocytes and epithelioid granulomas, compatible with the diagnosis of inflammatory pseudotumor. Post-operative, MRI scans showed complete tumor resection. Patient underwent a 3-month oral corticosteroid therapy showing no signs of recurrence at the radiological follow-up. Primary intracranial inflammatory pseudotumors are very rare pathological entities that can mimic extra-axial tumors, and should take into consideration as a potential differential diagnosis. Complete microsurgical resection in combination with other treatments (steroids therapy, radiotherapy) is the most common treatment of choice and in associated to good outcome and low rate of recurrence.

Treatment and Prognosis of Inflammatory Pseudotumor of the Skull Base

Background Inflammatory pseudotumor (IPT) of the skull base is a rare, locally destructive lesion managed with a variety of treatments. We explore the impact of treatment on outcome and assess the prognosis of IPT.

Methods This is a retrospective review of IPT of the skull base at a tertiary academic medical center. The primary outcome was radiographic progression after treatment. Outcome versus tumor location was also examined and a prognostic model was developed using a logistic regression.

Results The demographics of 21 patients with IPT are reported. Treatment consisted of corticosteroids (in 80.1% of patients), disease modifying antirheumatic drugs (DMARDs; 33.3%), surgical resection (28.6%), radiation (23.8%), antibiotics (14.3%), chemotherapy (rituximab; 9.5%), and antivirals (4.8%). At 50.7 months, 50.8% had radiographic progression. Local therapy trended toward having a better response than systemic therapy (p = 0.60). IPT of the orbit required 2.4 treatment modalities, compared with 2.0 for pharyngeal IPT, and 1.3 for posterior skull base masses (p = 0.14). A total of 75% orbital IPT underwent radiographic progression, compared with 71% of pharyngeal IPT and 50% of posterior skull base masses (p = 0.62). Sixteen patients were used to create the logistic model of radiographic progression. The Cox–Snell R 2 was 0.71 (p = 0.03). No individual variables were statistically significant.

Conclusion To our knowledge, this is among the largest sample of cases describing the presentation, treatment, and prognosis of IPT of the skull base. Our data suggest that there may be an improved response with local therapy over systemic therapy and better prognosis among posterolateral skull base masses.

Esophageal inflammatory pseudotumor with low-dose corticosteroid therapy after surgery

Inflammatory pseudotumors of the esophagus are extremely rare, and the treatment has been controversial. Herein, we report a case of esophageal inflammatory pseudotumor with low-dose corticosteroid treatment following surgery. A 50-year-old woman with a 3-month history of progressive dysphagia and weight loss, was admitted to our hospital for examination and treatment. Esophagography and endoscopic examination revealed a mass present from the cervical esophagus to the upper thoracic esophagus with severe esophageal stricture. Ultrasound-guided fine needle aspiration cytology, boring biopsy, and mucosal incision-assisted biopsy reveal chronic inflammation, but histological diagnosis was not proven. Surgery was performed to confirm diagnosis and to relieve esophageal stricture. However, because of dense adhesions around the tumor, complete tumor resection was not achieved. Histopathological examination showed an inflammatory infiltrate with plasma cells, eosinophils, neutrophils, and lymphocytes, suggesting an inflammatory pseudotumor. After surgical resection, the esophageal stricture remained, possibly due to the residual tumor. We used a postoperative low-dose steroid treatment that resulted in complete resolution. There has not been any evident sign of recurrence for more than 2 years.

1064 nm Nd:YAG laser treatment of melanocytic nevi of the external auditory canal: a retrospective study of 15 cases

The aim of this study was to evaluate the efficacy and safety of 1064 nm neodymium-doped yttrium-aluminum-garnet laser treatment of melanocytic nevus of the external auditory canal. Retrospective chart review of 15 patients operated by 1064 nm Nd:YAG laser in single center. Data from charts and video documentation were collected and analyzed. Between November 2017 and November 2018, 15 patients underwent 1064 nm Nd:YAG laser treatment for melanocytic nevus of the external auditory canal were analyzed in the study. The size of melanocytic nevus ranged from 4 to 8 mm in diameter. A gross total removed was achieved in all cases. Two patients received two sessions of Nd:YAG laser treatments, and the remaining thirteen patients received only one session. After laser treatment, wounds healing well and the average epithelialization time was 2.3 weeks. The mean follow-up was 12 months. There were no recurrence and adverse side effects in all cases. This research supports the use of 1064 nm Nd:YAG laser as a safe and efficacious treatment for melanocytic nevus of the external auditory canal.

Clinical significance of IgG4 in sinonasal and skull base inflammatory pseudotumor

INTRODUCTION

Inflammatory pseudotumor (IPT) in the sinonasal cavity and skull base region is benign non-neoplastic inflammatory process. However, IPT can mimic malignant tumor or infectious disease and there are difficulties in confirmation of diagnosis. The aim of study is to evaluate the clinical significance of immunoglobulin G4 (IgG4) in IPT in terms of steroid response and differential diagnosis with other skull base infiltrative lesions.

METHODS

Medical records were reviewed retrospectively from 1998 to 2016. Subjects diagnosed with IPT by surgical biopsy were enrolled. IgG4 positivity was defined as IgG4/IgG ratio > 0.4. Additionally, IgG4/IgG ratio was calculated in eight skull base osteomyelitis (SBO) patients.

RESULTS

Twenty-six IPT patients were included and the average age was 52.3 years, and 57.7% were male and 42.3% were female. Most lesions were involved in the sinuses (88.5%) and the incidence of extension beyond the sinuses itself was as follows: the cheek/hard palate/parapharynx (15.4%), orbit (61.5%), skull base (57.7%), and dura or brain (23.1%). All IPT cases revealed IgG4 + plasma cells and IgG4/IgG ratio over 0.4 was detected in 42.3% (11/26) of cases. In case of SBO, no patients had IgG4/IgG ratio exceed 0.4. Main treatment modality was systemic steroids (61.5%) and other modalities were used: surgery (3.8%), immunosuppressant (7.7%), radiotherapy (30.8%), or a combination of these modalities (15.4%). Steroid responses were not significantly different, but IgG4-positive group tended to have better response to steroid therapy.

CONCLUSIONS

IgG4-positive and IgG4-negative IPT patients revealed no differences in involvement sites, clinical course, and steroid responses. However, IgG4/IgG ratio and IgG4 + plasma cell count can provide a diagnostic clue for infiltrative skull base lesions such as IPT and a differential diagnosis of SBO.

Inflammatory myofibroblastic tumor of the lumbar spinal canal: A Case Report With Literature Review

RATIONALE

Inflammatory myofibroblastic tumor (IMT) is a rare type of mesenchymal tumor. IMT can arise in multiple anatomic locations. IMT of the lumbar spinal canal is exceptionally rare.

PATIENT CONCERNS

Here, we report the case of a 56-year-old male patient with an IMT who was in good health until 1 year prior to admission, when he began experiencing pain in both lower extremities and the lower back.

INTERVENTIONS

A space-occupying lesion in the lumbar canal was identified by magnetic resonance imaging and then surgically resected.

DIAGNOSES

Histopathological analysis of the lesion revealed a composition of mucous edema, inflammatory cells, collagenous fibers, and spindle cells that were diffuse and positive for smooth muscle actin and CD68; focal positive for vimentin and desmin; and negative for CD34 (marker of vascular endothelial cells), CD21, CD23, CD35, S-100, Epstein-Barr virus infection, Ki-67, and anaplastic lymphoma kinase. Thus, the diagnosis was an IMT of the lumbar canal.

OUTCOMES

In the spinal canal, IMT should be considered in the evaluation of tumors although it is a very rare diagnosis. It is a benign lesion, but it has potential for invasion and recurrence.

LESSONS

There are no characteristic imaging features of these tumors, but they can be addressed by complete surgical excision. Patients with these lesions should undergo frequent long-term follow-up to detect and address recurrence.

Sinonasal Inflammatory Myofibroblastic Tumor with Anaplastic Lymphoma Kinase 1 Rearrangement: Case Study and Literature Review

Inflammatory myofibroblastic tumors (IMTs) are rare mesenchymal tumors initially described in the lung. About half of them exhibit expression of the ALK1 protein, generally resulting from a gene rearrangement. Paranasal sinus IMTs are extremely uncommon, and gene rearrangement of ALK1 is very rare in this localization. A 47-year-old woman presented with rapidly progressive vision loss in her left eye. Clinical and imaging work-up revealed a tumor invading the left ethmoidal and sphenoidal sinuses and extending into the nasal cavity, the orbit and the skull base. Complete tumor resection was performed using an endonasal approach. Pathological examination revealed a paranasal localization of IMT, positive for ALK1 immunostaining. FISH analysis showed an ALK1 gene rearrangement. This case illustrates the local aggressive potential for IMTs. Treatment is primarily surgical, but targeted therapies (crizotinib) might be a solution for ALK1 rearranged cases with a poor prognosis.

Extrasinonasal infiltrative process associated with a sinonasal fungus ball: does it mean invasive fungal sinusitis?

PURPOSE

Invasive fungal sinusitis (IFS) has rarely been reported to develop from non-IFS. The purpose of this study was to disclose the nature of the extrasinonasal infiltrative process in the presence of a sinonasal fungus ball (FB).

METHODS

We retrospectively reviewed the medical records, computed tomography, magnetic resonance images of 13 patients with sinonasal FB and the extrasinonasal infiltrative process. Based on histology and clinical course, we divided the extrasinonasal infiltrative process into IFS and the nonfungal inflammatory/infectious process (NFIP). The images were analyzed with particular attention to the presence of cervicofacial tissue infarction (CFTI).

RESULTS

Of the 13 patients, IFS was confirmed in only one, while the remaining 12 were diagnosed to have presumed NFIP. One patient with IFS died shortly after diagnosis. In contrast, all 12 patients with presumed NFIP, except one, survived during a mean follow-up of 17 months. FB was located in the maxillary sinus (n=4), sphenoid sinus (n=8), and both sinuses (n=1). Bone defect was found in five patients, of whom four had a defect in the sphenoid sinus. Various sites were involved in the extrasinonasal infiltrative process, including the orbit (n=10), intracranial cavity (n=9), and soft tissues of the face and neck (n=7). CFTI was recognized only in one patient with IFS.

CONCLUSION

In most cases, the extrasinonasal infiltrative process in the presence of sinonasal FB did not seem to be caused by IFS but probably by NFIP. In our study, there were more cases of invasive changes with the sphenoid than with the maxillary FB.

Discrepant lesion size estimated on T1- and fat-suppressed T2-weighted MRI: diagnostic value for differentiation between inflammatory pseudotumor and carcinoma of the nasopharynx

PURPOSE

Nasopharyngeal inflammatory pseudotumor (NIPT) is hard to differentiate from infiltrating nasopharyngeal carcinoma (NPC) on conventional magnetic resonance imaging (MRI). The purpose of this study is to determine whether discrepant lesion sizes estimated on T1- and fat-suppressed T2-weighted images can help distinguish between NIPT and NPC.

METHODS

We retrospectively reviewed MRI data of histologically proven 14 NIPTs and 18 infiltrating NPCs. We measured the area of the lesion on contrast-enhanced T1-weighted, unenhanced T1-weighted, and fat-suppressed T2-weighted images by placing the largest possible polygonal region-of-interest within the lesion at the same level. Using lesion size measured on contrast-enhanced T1-weighted image as the reference, we calculated and compared area ratio of T1 (ART1) and area ratio of T2 (ART2) between NIPTs and NPCs. For validation, we also undertook a double-blinded study by two reviewers and assessed the diagnostic performance and interobserver agreement.

RESULTS

For NIPTs, ART2 (median, 0.48; range, 0.18-0.97) was statistically significantly less than ART1 (median, 1.01; range, 0.80-1.99), while these values were not significantly different for NPCs. The interobserver agreement in differentiating between NIPT and NPC was good, with a sensitivity of 93% and a specificity of 83%-94%.

CONCLUSION

In contrast to NPCs, NIPTs appear smaller on fat-suppressed T2-weighted images than on T1-weighted images. This discrepancy in the lesion size estimated on T1-weighted and fat-suppressed T2-weighted images may provide a simple and consistent way to differentiate between NIPTs and NPCs on conventional MRI.

Inflammatory Pseudotumor of the Infraorbital Nerve: A Rare Diagnosis to Be Aware of

Inflammatory pseudotumor (IPT) is a rare benign mass-forming disease that can arise anywhere throughout the body, mimicking a wide spectrum of other conditions. Its diagnosis can be challenging, especially when it involves uncommon sites. The authors report a patient of an atypical localization of IPT, occurred as an enlarging bulk in the infraorbital nerve channel in a patient who presented with facial numbness. Clinical and radiological aspects similar to schwannoma led to misdiagnosis and over-treatment. The differential diagnosis of an infraorbital mass should include IPT and the least invasive treatment should be preferred, as steroid therapy being the first-line treatment for IPT.

Atypical culture-negative skull base osteomyelitis masquerading as advanced nasopharyngeal carcinoma

Skull base osteomyelitis typically arises as a complication of otogenic or sinonasal infections in immunocompromised patients. A much rarer entity, atypical skull base osteomyelitis is not associated with an obvious infective source. Atypical and culture-negative skull base osteomyelitis is even rarer and hampers diagnosis, as its clinical presentation is remarkably similar to skull base neoplasms. We report a case of extensive skull base osteomyelitis with orbital apex syndrome and multiple lower cranial nerve palsies which initially masqueraded as possible advanced nasopharyngeal carcinoma. Extensive investigations and consult with an infectious diseases specialist aided in elucidation of the correct diagnosis. Through this article, we emphasize that skull base osteomyelitis must be considered in the setting of headache, cranial neuropathies, elevated inflammatory markers and abnormal imaging findings. Early tissue sampling for histology, stainings and cultures and prompt appropriate treatment may prevent or arrest further complications.

Inflammatory Pseudotumors of the Skull Base: Meta-Analysis

OBJECTIVE

To describe the presentation, treatment, and outcome of inflammatory pseudotumors (IPs) of the skull base.

DATA SOURCES

English-language articles in PubMed, Web of Science, and EMBASE from earliest available through April 2014.

STUDY SELECTION

Articles were identified using a keyword search for "inflammatory pseudotumor," "inflammatory myofibroblastoma," or "plasma cell granuloma," including a keyword localizing to the skull base.

DATA EXTRACTION

One hundred papers with 157 cases met inclusion criteria. History, tumor site, initial and subsequent treatment, outcomes, and complications were extracted. Student t test, z test, and analysis of variance were used to analyze demographics, symptoms, sites involved, and outcomes. Odds ratios for site versus initial treatment were calculated.

DATA SYNTHESIS

At diagnosis, average patient age was 41 years. Approximately 70% of lesions primarily involved the anterior skull base, 29% the lateral skull base, and 1.2% the occiput. The most common initial treatments were steroids (44%), surgery (28%), and surgery with steroids (16%). Anterior lesions were 55.8 times more likely than lateral lesions to be treated initially with steroids (CI, 14.7-212). Seventy-six percent of patients had stable or resolved symptoms after a single course of treatment.

CONCLUSION

Diagnosis of skull base IP requires ruling out other aggressive pathologies, such as malignancy and infection, and maintaining a high index of suspicion. Surgery is favored for lesions that can be removed in toto with minimal morbidity, as well as steroids for those sites where anatomy limits complete resection, such as within the orbit, cavernous sinus, or brain. An option for larger lesions involving vital anatomy is debulking, followed by postoperative steroids.

Inflammatory Myofibroblastic Tumor of the Left Sphenoid and Cavernous Sinus Successfully Treated with Partial Resection and High Dose Radiotherapy: Case Report and Review of the Literature

Inflammatory myofibroblastic tumors, also known as plasma cell granulomas or inflammatory pseudotumors, are uncommon lesions that are known to arise in many areas of the body. They are uncommonly found in the skull base region where effective treatment can be difficult. Steroids and radiation therapy with gross total excision when possible remain the treatments of choice. However, the dosing of radiation remains controversial and many patients develop relapse despite medical management. We present the case of a patient who had an inflammatory myofibroblastic tumor of the sphenoid bone and cavernous sinus. He underwent partial surgical resection and transient steroid therapy. This was followed by high-dose fractionated radiotherapy. The patient demonstrated significant resolution in symptomatology and evidence of disease-free progression on repeat imaging. 

Recurrent inflammatory myofibroblastic tumor of the inguinal region: A case report and review of the literature

Inflammatory myofibroblastic tumors (IMTs) of the inguinal region are exceptionally rare. The current study reported the case of a 49 year-old male patient with IMT, who presented with a fever, night sweats, anorexia, loss of weight and frequent urination. Computed tomography (CT) revealed a lesion occupying the soft tissue of the right inguinal region and surgery was performed to resect the lesion. Histopathological analysis of the lesion revealed a composition of spindle and inflammatory cells, including plasma cells and lymphocytes. In addition, immunohistochemical analysis demonstrated that the tumor cells were positive for CD34, vimentin, actin, Ki-67, B cell lymphoma-2, CD99, epithelial membrane antigen and CD38; however, tumor cells were negative for CD117, desmin, anaplastic lymphoma kinase and creatine kinase. Thus, the patient was diagnosed with IMT and was advised to return for regular follow-up appointments. Subsequently, the patient developed a local recurrence 12 months following the initial surgery. Of note, the histopathological characteristics of the recurrent lesions were consistent with those of the initial specimen. Thus, a second surgery was performed, followed by fractionated radiotherapy (FRT). At 3 and 6 months following the FRT, magnetic resonance imaging scans did not indicate tumor recurrence or metastasis. In conclusion, surgical excision is the current recommended treatment for IMT; however, for cases similar to that of the current study, which are not successfully controlled by surgical excision, radiotherapy should be considered and long-term follow-up is essential.

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 myofibroblastic tumor: an unusual mimicker of childhood intrathoracic tuberculosis

Inflammatory myofibroblastic tumors are rare lesions of uncertain etiology that are often difficult to diagnose because of their myriad clinical presentations. Not uncommon, they mimic persistent pneumonia. We report a 4-year-old girl who presented with prolonged pyrexia, weight loss, severe anemia, hepatosplenomegaly, and nonresolving pneumonia. Initial investigations including flexible bronchoscopy and bronchial washing for usual causes of persistent pneumonia, such as tuberculosis and other infections, were negative. Chest computed tomography revealed a well-defined lesion involving the lingula and left upper lobe with extension into the subpleural space. Pleural tap and biopsy was also noncontributory. Thoracoscopic biopsy was suggestive of an inflammatory myofibroblastic tumor. As the lesion was encasing the major vessels, it was considered inoperable. The patient did not respond to steroid therapy and etoricoxib and later succumbed to the illness. This uncommon tumor should be considered in the differential diagnosis of children who presented with unresolving consolidation with pyrexia.

Inflammatory myofibroblastic tumour of the skull base

Inflammatory myofibroblastic tumors (IMTs) are rare benign clinical and pathological entities. IMTs have been described in the lungs, abdomen, retroperitoneum, and extremities but rarely in the head and neck region. A 38-year-old man presented with headache, right exophthalmia, and right 6th nerve palsy. A CT scan revealed enlargement of the right cavernous sinus and osteolytic lesions of the right sphenoid and clivus. MR imaging showed a large tumor of the skull base which was invading the sella turcica, right cavernous sinus, and sphenoidal sinus. A biopsy was performed and revealed an IMT. Corticosteroids were given for 3 months but were inefficient. In the framework of our pluridisciplinary consultation, fractionated conformal radiotherapy (FRT) was indicated at a low dose; 20 Gy in 10 fractions of 2 Gy over 12 days were delivered. Clinical response was complete 3 months after FRT. Radiological response was subtotal 6 months after FRT. Two years later, the patient is well.

Progressive tumefactive fibroinflammatory lesion of the infratemporal fossa treated by radiation therapy

Tumefactive fibroinflammatory lesion (TFIL) is a rare benign tumor in the head and neck region. We present a case of a 40-year-old female with a benign but progressive lesion of the infratemporal fossa, which was diagnosed as TFIL. Patient responded briefly to a course of steroid treatment but eventually showed progression and was unresponsive to further steroids. She was then treated with external beam radiation to a dose of 60 Gy in 30 fractions. After radiation a slow, gradual decrease in tumor size was noted over the course of years and she is free of disease after more than 11 years of follow-up. The major long-term side effect this patient developed was an expected unilateral radiation-induced retinopathy, due to the close proximity of the lesion to the orbit. The dilemma of treatment of benign disease with radiation with potential long-term complications is discussed and a review of the literature on TFIL is presented.

Recurrent inflammatory pseudotumor of the jaw with perineural intracranial invasion demonstrating sustained response to Rituximab

Corticosteroids are the mainstay of treatment of inflammatory pseudotumor (IPT) of the head and neck; however, involvement of the skull base and mandible can be unresponsive to steroids and require surgical resection. IPT is known to usually contain a CD20+ lymphocyte subgroup. Rituximab, a chimeric anti-CD20 antibody, has been successfully utilized in the treatment of other CD20+ diseases, including the similar idiopathic orbital inflammatory disease. This is the first report to describe successful treatment with Rituximab of a recurrent IPT of the mandible with trigeminal spread and leptomeningeal involvement with clinical and radiologic evidence demonstrating a sustained response to therapy.

Inflammatory pseudotumor of the skull base involving fissura petrooccipitalis: a rare case with challenging diagnosis

Inflammatory pseudotumor (IPT) is a benign entity that may present as a solid mass mimicking a malignant neoplasm. Histologically, they are composed of varying proportions of myofibroblastic spindle cells, lymphocytes, and plasma cells. Skull base IPT is rare and usually occurs in adults with no sex predilection. The skull base IPT typically presents with headache, and/or cranial nerve palsy. There is no consensus regarding treatment of skull base IPT due to its rarity. Surgical resection and corticosteroid therapy have generally been used. The preoperative diagnosis of skull base IPT is usually difficult due to its nonspecific clinical and radiologic features. We report a case of a 42-year-old woman with IPT originating from the skull base. To our knowledge, this is the first case of IPT invading fissura petrooccipitalis. When a mass in the skull base appears hypointense on T2-weighted imaging with aggressive growth and bony destruction, IPT should be considered in the differential diagnosis.

Spontaneous hearing improvement in a patient with an inflammatory myofibroblastic tumor of the temporal bone

Inflammatory myofibroblastic tumor (IMT) is a rare lesion of unknown etiology and difficult diagnosis. The treatment of IMT is controversial. We report a case of IMT of the temporal bone in a young man presenting with a progressive hearing loss. Three years after diagnosis, partial hearing improvement has been documented.

Inflammatory pseudotumor of the tonsil

Inflammatory pseudotumor is an unusual benign but potentially invasive lesion. In the head and neck area, it mainly involves the orbit and paranasal sinuses. We present a case in tonsil and neck. After tonsillectomy and steroid therapy, there has been no recurrence.

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.

Inflammatory pseudotumor of the trigeminal nerve: a neoplastic mimic you do not want to miss

Inflammatory pseudotumor is a rare non-neoplastic mass that may clinically and radiologically mimic a spectrum of benign and malignant neoplasms. It is uncommon in the head and neck and particularly rare at the skull base. We present a case of pseudotumor originating from the trigeminal nerve in a patient who presented with headache and facial numbness. A high index of suspicion is necessary to diagnose this benign but locally aggressive entity.

Sphenoid wing inflammatory pseudotumor mimicking a clinoidal meningioma: case report and review of the literature

BACKGROUND

Inflammatory pseudotumor is a nonneoplastic process of unknown etiology most frequently involving the lungs and orbits. Primary intracranial inflammatory pseudotumors are exceptionally rare. The authors report a rare case of clinoidal inflammatory pseudotumor mimicking a medial sphenoid wing meningioma.

CASE DESCRIPTION

A 24-year-old woman presented with visual diminution and proptosis in the left eye for one and a half years. Imaging revealed a medial sphenoid wing mass, which was surgically decompressed. Histopathology confirmed the diagnosis of inflammatory pseudotumor after which she was treated with steroids. The patient is doing well at 3 months' follow-up with resolution of proptosis and no further diminution of vision.

CONCLUSION

Inflammatory pseudotumors can mimic a malignant tumor both radiologically and clinically. The treatment options consist of surgery, high-dose steroids, irradiation, and chemotherapeutic agents with variable therapeutic response. Intracranial involvement due to inflammatory pseudotumor is exceptionally rare. The importance of recognizing and appropriately diagnosing this rare intracranial pathology lies in prognostication and avoidance of overzealous treatment.