Inflammatory myofibroblastic tumour of the spinal cord: case report and review of the literature

Management Strategies of Plasma Cell Granuloma Involving the Central Nervous System: A Systematic Review of the Literature

BACKGROUND

Plasma cell granuloma (PCG) is a rare clinical entity seen in the neurosurgical literature. It has often been referred to as inflammatory myofibroblastic tumor or inflammatory pseudotumor. No well-defined management guidelines exist in the literature.

METHODS

Using PRISMA guidelines, we systematically reviewed the literature in PubMed and Google Scholar using MeSH terms: intracranial plasma cell granuloma, myofibroblastic tumor, intracranial pseudotumor, spinal plasma cell granuloma. We analyzed the clinical presentation, treatment strategies, clinical outcomes, and follow-up across different studies.

RESULTS

Eighty-three studies were included presenting 108 cases. Primary extracranial disease was seen in 4 patients and primary central nervous system (CNS) disease in 104. In the combined cohort, multicompartmental disease was seen in 22 (20.8%) patients. Headache (n=40, 42.59%) was the most common clinical symptom. Surgical excision (n=86, 79.6%) was the most common primary treatment used. Radiation therapy, steroids, and chemotherapy (methotrexate/6-mercaptopurine/rituximab) were also used. Disease recurrence was noted in 25 (33.3%) patients and residual disease in 33 (30.5%). Mortality was seen in 4 (3.7%) patients. In the cranial PCG subgroup (n=87), 81 (93.1%) patients had solitary lesions, and 6 (6.8%) had multiple lesions. Recurrence after primary surgery was noted in 27.58% (n=24). In the spinal PCG subgroup (n=17), the thoracic spine was the most common location (n=9, 52.9%) and recurrence was seen in 5.84% (n=1).

CONCLUSIONS

Combination of multiple treatment modalities is needed when approaching this complex disease. Spinal PCGs respond favorably to gross total excision, with a low recurrence rate. Cranial PCGs warrant intense follow-up with secondary chemotherapy/radiation/steroids in recurrent cases.

Treatment modalities of ALK-positive relapsed/refractory inflammatory myofibroblastic tumor of the brain and lungs in 7-year-old girl: case-based reviews

PURPOSE

Inflammatory myofibroblastic tumor (IMT) belongs to mesenchymal neoplasm of intermediate malignancy in WHO classification. Primary CNS disease or CNS metastases (CNS-IMT) occur in minority. We describe a case of relapsed/refractory IMT of lungs with multiple brain metastases in young child who achieved long-term complete response after alectinib. This systematic review also summarizes treatment modalities and outcome of children and adolescent with CNS-IMT.

METHODS

PRISMA 2020 guideline was applied to select an article from PubMed, Scopus, and Cochrane databases without time limits. This review focused on children and adolescent 0-24 years of age with CNS-IMT or inflammatory pseudotumor (CNS-IPT). The clinical characteristics and treatment outcome were explored.

RESULTS

A total of 51 patients in 49 publications were identified. Median age of patients with CNS-IMT/IPT was 15-year-old and 60.8% were male. The most common location of tumor was cerebral cortex (54.9%). Complete resection of CNS-IMT/IPT was performed in 27 cases with 100% complete response and 18.5% recurrence. Nearly half of patients who received partial resection without adjuvant therapy experienced progressive disease, while the contrast group totally achieved partial response. Overall responses in 7 patients treating with ALK inhibitors were 57.1% durable complete response and 42.9% transient partial response.

CONCLUSION

First-line treatment of CNS-IMT/IPT is complete resection. Patients who received partial tumor removal might have benefit from adjuvant therapy. ALK inhibitors reveal a promising result in unresectable CNS-IMT/IPT. Our case has shown a success in treating relapsed and refractory CNS-IMT as well as the primary site using 2nd-generation ALK inhibitor.

HIV-related bilateral inflammatory myofibroblastic tumors of the adrenal gland: a case report and literature review

BACKGROUND

Inflammatory myofibroblastic tumor (IMT) is a rare disease that mostly occurs in younger people and is located in the lungs in the general population. We report a rare case of adrenal IMT in a patient with HIV infection, which is believed to be the first of its kind worldwide.

CASE PRESENTATION

We present a rare case of a 44-year-old man with HIV infection who was diagnosed with adrenal IMT. The patient refused regular highly active antiretroviral therapy 13 years ago until he was admitted to hospital after an adrenal mass was found. The patient underwent successful computed-tomography-guided needle biopsy, and pathological analysis showed fibroblastic-myofibroblastic proliferation with inflammatory infiltration, which confirmed a diagnosis of IMT. We failed to perform complete resection of the tumor because of its diffuse invasion. The patient was complicated with severe multiple pulmonary infections postoperatively because of immunodeficiency, which eventually caused his death 2 months later.

CONCLUSION

Differential diagnosis of IMT is difficult, and tumor biopsy is an essential means of diagnosis. Surgical resection is preferred for both adrenal and HIV-related IMTs. Conservative treatment should be considered when there are technical difficulties with complete resection, and most patients have achieved good outcomes. However, more cases and longer follow-up are warranted to confirm long-term outcomes of HIV-related IMT.

Fulminant spinal cord compression caused by postradiation inflammatory pseudotumor with rapid response to steroids: case report

Radiation therapy continues to play an extremely valuable role in the treatment of malignancy. The effects of radiation therapy on normal tissue can present in a delayed fashion, resulting in localized damage with pseudomalignant transformation, producing a compressive effect on the spinal cord or exiting nerve roots. Infiltration of inflammatory cells and the subsequent fibrotic response can result in the development of an inflammatory pseudotumor (benign tumor-like lesion) with subsequent mass effect. Herein, the authors present a rare case of inflammatory pseudotumor with fulminant cervicothoracic cord compression, developing 7 years after radiation therapy for breast cancer. The lesion recurred following resection but subsequently displayed complete and rapid resolution following steroid therapy. To the best of the authors' knowledge, no previous studies have reported such an incident.

IMAGING DIAGNOSIS - MAGNETIC RESONANCE IMAGING OF INTRACRANIAL INFLAMMATORY FIBROSARCOMA IN A MIXED BREED DOG

An 8-year-old mixed-breed dog presented with progressive behavioral changes and altered mentation. Magnetic resonance imaging (MRI) of the brain revealed an olfactory and frontal lobe extra-axial mass. The mass exhibited the following MRI signal intensity characteristics: T2W mixed, T1W iso- to hypointense, FLAIR hyperintense, and strong contrast enhancement. The mass was removed with cavitronic ultrasonic surgical aspirator (CUSA) assisted neurosurgery. Based on histopathological appearance and immunohistochemistry, the diagnosis of inflammatory fibrosarcoma was made. To our knowledge, this is the first report describing MRI characteristics of intracranial inflammatory fibrosarcoma in the veterinary literature.

Inflammatory myofibroblastic tumor in the intradural extramedullary space of the lumbar spine with spondylolisthesis: case report and review of the literature

An inflammatory myofibroblastic tumor (IMT) is a rare disease entity reported to arise in various organs but still thought to be a neoplastic or reactive inflammatory condition controversially. The author reports an extremely rare case of intradural extramedullary IMT of lumbar spine which was presenting radiculopathy and neurogenic intermittent claudication due to concomitant spondylolisthesis.

Neurological, imaging and pathological features of a meningeal inflammatory pseudotumour in a Maltese terrier

A five-year eight-month-old Maltese terrier was presented with a 3-week history of progressive paraparesis and pelvic limb ataxia. Neurological examination was consistent with a lesion involving the T3-L3 spinal cord segments. Myelogram and magnetic resonance imaging revealed a spherical, intradural-extramedullary mass lesion at T13/L1. A dorsal laminectomy, durotomy and debulking of the mass were performed. Histopathologic examination revealed a highly cellular tissue, most likely of mesenchymal origin, infiltrated by many lymphocytes, macrophages and neutrophils. The pathological diagnosis of an inflammatory pseudotumour was made. Postsurgical analgesia was achieved with opioids and 2 mg/kg carprofen twice daily for 5 days. When the histopathological diagnosis was made, a tapering course of 1 mg/kg prednisolone twice daily was prescribed, with dose reduction by approximately 50% every 4 to 6 weeks over a 4-month period. Magnetic resonance imaging was repeated at 22, 32 and 85 weeks postsurgery; no signs of regrowth could be detected and the patient recovered with residual mild paraparesis. Inflammatory pseudotumour has not been documented previously at this site in dogs and, although rare, should be considered in the differential diagnosis of a focal mass lesion affecting the spinal cord. Surgical debulking and immunomodulatory therapy can be curative.

Imaging features of meningeal inflammatory myofibroblastic tumor

BACKGROUND AND PURPOSE

Meningeal inflammatory myofibroblastic tumor (IMT) has been rarely reported, and its prognosis is still unclear. Our purpose was to describe the imaging features of patients with meningeal IMT and their results on follow-up studies.

MATERIALS AND METHODS

Twenty-four MR images in 10 consecutive patients with pathologically proved meningeal IMTs were retrospectively evaluated, focusing on the lesion distribution, signal intensity (SI), and contrast-enhancement pattern with a review of the clinical records.

RESULTS

Eight patients with intracranial IMT showed localized (n = 4) or diffuse (n = 4) dural thickening, a single mass (n = 5) or 2 (n = 2) dural-based masses with surrounding edema, dural venous sinus thrombosis (n = 5), and leptomeningeal involvement (n = 5). Extracranial involvement of the mastoid (n = 2) and orbit (n = 2) was also associated. Each of the 2 patients with intraspinal IMT showed a dural-based mass and a segmental dural thickening, respectively. All of the thickened dura showed low SI on T2-weighted images, iso-SI on T1-weighted images, and diffuse contrast enhancement. Variable recurrences with dural-based masses, mastoid involvement, or nasolacrimal duct involvement were observed in all 4 patients with diffuse intracranial IMT, but not in the others.

CONCLUSIONS

Localized or diffuse dural thickening of T2 low SI and diffuse contrast enhancement combined with dural-based masses are a common MR imaging finding of meningeal intracranial IMT. Adjacent leptomeningeal involvement and dural venous sinus thrombosis are frequently associated. The diffuse type has a tendency toward recurrence.

Inflammatory myofibroblastic tumor of the central nervous system and its relationship to inflammatory pseudotumor

Inflammatory myofibroblastic tumor (IMT) is a distinctive spindle cell lesion and occurs primarily in soft tissue. Recent evidence suggests a neoplastic nature, although historically, both neoplastic and nonneoplastic processes were combined in this category. Originally described as a nonneoplastic process, the term inflammatory pseudotumor (IP) has been used synonymously with IMT. IMTs have been linked to ALK gene (2p23) rearrangements, and some have suggested an association with the human herpesvirus 8 (HHV-8). IMT in the central nervous system (CNS) is rare, its characteristics are poorly defined, and its relation to similar tumors at other sites is unclear. To better characterize IMT within the CNS, we studied clinicopathologic features of 6 IMTs and compared them with 18 nonneoplastic lesions originally classified as IP. The IMT group consisted of 2 male and 4 female patients with a median age of 29 years. Of the six IMTs, 5 occurred within the cerebral hemispheres, and one was in the posterior fossa. All tumors were composed of neoplastic spindle cells and a variable amount of inflammatory infiltrate. Eighteen IPs included in this study consisted of predominantly inflammatory masses occasionally seen in the setting of systemic diseases. Only 1 IMT and none of the IPs recurred during the follow-up period. Four IMTs had either ALK protein overexpression or 2p23 rearrangement, and 1 case demonstrated both. None of the IPs were positive for ALK. Neither IMT nor IP cases demonstrated HHV-8 expression. We suggest that IMT in the CNS is distinct from the nonneoplastic IP, and distinguishing IMT from nonneoplastic lesions should enable better decisions for patient management.

Inflammatory pseudotumor of the peroneal nerve: case report and literature review

Inflammatory pseudotumors (IPTs) are a group of lesions of obscure etiology. Although they are presumably reactive, their exact pathogenesis is unknown. Inflammatory pseudotumors are identified in different organs; however, IPTs of the peripheral nerves have been rarely reported in the English literature. We report a 44-year-old woman who presented with left foot drop. Examination revealed a thickening in the posterolateral aspect of the popliteal fossa and features consistent with peroneal nerve palsy. Magnetic resonance imaging revealed a mass that may represent a Baker cyst or perineural sheath mass that was excised. After pathological examination, the case was diagnosed as IPT of peroneal nerve, and the patient received no further therapy. Inflammatory pseudotumors of the peripheral nerves, although rare, should always be of consideration in the differential diagnosis of peripheral nerve nodular mass lesions. They can mimic neoplastic nerve sheath lesions, clinically and radiologically. However, they are amenable to surgical cure with nerve-sparing surgery. Thus, despite their rarity, on dealing with neural S100 negative lesion, their inclusion is mandatory to avoid an unnecessary and a rather aggressive surgery.

Inflammatory myofibroblastic tumor on intercostal nerve presenting as paraneoplastic pemphigus with fatal pulmonary involvement

Inflammatory myofibroblastic tumors (IMTs) are benign neoplasms that can occur at different anatomic sites with nonspecific clinical symptoms. A 48-yr-old woman presented with a 2-month history of a relapsed oral ulcer, progressive dyspnea, and a thoracic pain induced by breathing. A tumorous mass was noticed in the right costodiaphragmatic recess on chest computed tomography and magnetic resonance imaging, and the patient underwent a right costotransversectomy with excision of the tumor, which originated from the 12th intercostal nerve. Histology and immunohistochemistry showed that the tumor was an IMT of the intercostal nerve. The patient's postoperative course was not favorable; dyspnea persisted after surgery, and a progressive pulmonary compromise developed. The cause of the respiratory failure was found to be bronchiolitis obliterans, which in this case proved to be a fatal complication of paraneoplastic pemphigus associated with an IMT. This case of IMT of the spinal nerve in the paravertebral region is unique in terms of its location and presentation in combination with paraneoplastic pemphigus, which is rare. A brief review of the heterogeneous theories concerning the pathogenesis, clinicopathological features, and differential diagnosis of this disease entity is presented.

Inflammatory myofibroblastic tumor of the ulnar nerve. Case report and review of the literature

Inflammatory myofibroblastic tumors with involvement of cranial and peripheral nerves are exceedingly rare. The authors present the case of a 67-year-old man with an inflammatory myofibroblastic tumor of the left ulnar nerve, which was identified intraoperatively and mimicked a malignant neoplastic lesion. Histopathological examination revealed loosely structured fibrous tissue and collagen deposits intermingled with patchy infiltrates of lymphocytes, plasma cells, and histiocytes penetrating the endo- and epineurium of the affected nerve fascicles. There was strong expression of vimentin and actin in spindle cells throughout the lesion. The histiocytes were CD68- and major histocompatibility complex class II-positive, but lacked CD1a expression. A review of the literature revealed nine histopathologically confirmed cases of inflammatory myofibroblastic tumors involving peripheral or cranial nerves in which slight differences in histopathological features and surgical management were found, which are discussed here.

ALK positive inflammatory myofibroblastic tumour of the pineal region

Inflammatory myofibroblastic tumours (IMTs) are an uncommon spindle cell neoplasm with a dense inflammatory infiltrate, usually encountered in children. IMTs of the central nervous system are extremely rare. This report describes the case of an IMT in a 61 year old man, in the pineal region. The tumour was completely excised, and immunohistochemistry demonstrated anaplastic lymphoma kinase 1 expression. There was no tumour recurrence during 18 months of follow-up. Our case extends both the age range and sites of occurrence of this rare tumour.