Pulmonary inflammatory myofibroblastic tumor and IgG4-related inflammatory pseudotumor: a diagnostic dilemma

Differential diagnosis of IgG4-positive plasma cells in the lung

The recognition of immunoglobulin G4-related disease (IgG4-RD) as an entity in the pancreaticobiliary tract was followed by a slew of papers describing inflammation and fibrosis containing IgG4-positive plasma cells in a variety of sites including the respiratory tract, leading to the hypothesis that these abnormalities were attributable to IgG4-RD. Predictably, pathologists began to see requests from clinicians to perform IgG4 immunohistochemistry in lung biopsies "to rule out IgG4-RD". Several years later, the notion that IgG4-RD would prove to be the underlying cause of a wide array of fibroinflammatory lesions in the lung has not panned out as promised. To the contrary, it has become clear that IgG4-positive plasma cells are not specific for IgG4-RD, and that large numbers of IgG4-positive plasma cells can be encountered in other well-defined entities, including inflammatory myofibroblastic tumor and nodular lymphoid hyperplasia, as well as in lymphoplasmacytic infiltrates in other entities, including connective tissue disease and idiopathic forms of interstitial lung disease. It has also become clear that raised serum IgG4 levels can occur in settings other than IgG4-RD. These observations suggest that true IgG4-RD of the lung is far less common than previously surmised. Pathologists must familiarize themselves with mimics of IgG4-RD in the lung and exercise caution before attributing lymphoplasmacytic infiltrates in the lung to IgG4-RD.

Inflammatory myofibroblastic tumor of the lung involving the central nervous system in pediatric patients

INTRODUCTION

The inflammatory myofibroblastic tumor (IMT) is a very rare lesion with an incidence of less than 0.1% of total neoplasms and with main affection in the lungs. Involvement in the central nervous system is extremely rare, but with a much more aggressive course than IMT diagnosed in the rest of the body. We report the 2 cases presented in our neurosurgery department to date; both were treated satisfactorily without intercurrences in 10 years of follow-up.

HISTORICAL BACKGROUND

The World Health Organization described the IMT as a distinctive lesion composed of myofibroblastic spindle cells accompanied by an inflammatory infiltrate of plasma cells, lymphocytes, and eosinophils.

CLINICAL PRESENTATION

Clinical manifestations of patients with CNS IMT vary and may consist of headache, vomiting, seizures, and blindness. Seizures are the most common symptom in patients with focal lesions.

DIAGNOSIS

The true origin of this entity remains to be elucidated, but to date, etiologies ranging from chromosomal alterations to autoimmune or postinfectious mechanisms have been described. Due to its rarity and non-specificity in imaging, the final diagnosis of IMT in the brain parenchyma relies on pathological examination.

MANAGEMENT

Treatment options are controversial and include total or subtotal removal, high-dose steroids, and radiation therapy. In the last decade, the development of ALK Tyrosine Kinase Inhibitors allows the possibility of chemotherapy in those patients harboring ALK mutations.

CONCLUSION

IMT is a rare tumor that can exceptionally be found in the CNS. The cause is still unknown although the different studies focus on a neoplastic origin. The diagnosis is based in the use of different modalities of imaging and with histological confirmation. Optimal management is gross total resection whenever possible, is the only established curative treatment. Further research with longer follow-up is needed to clarify the natural history of this rare tumor.

Inflammatory Myofibroblastic Tumour of the Sinonasal Tract with Orbital and Intracranial Extensions Simulating a Malignancy: A Case Report and Review of Literature

Inflammatory Myofibroblastic Tumour (IMT) is a rare pathology of unknown etiology. It is pathologically benign, but clinically locally invasive. We are herewith reporting a unique case of rapidly growing sinonasal IMT with orbital and intracranial extensions in a middle aged female patient masquerading as a malignancy. The lesion was excised endoscopically with margins and the patient is presently under close follow up. The report also reviews the common sites of involvement and management options available, based on a literature review.

Inflammatory pseudotumor and myofibroblastic inflammatory tumor. Diagnostic criteria and prognostic differences

INTRODUCTION

Inflammatory pseudotumor (IPT) and inflammatory myofibroblastic tumor (IMT) are two very rare entities that were formerly included in the same category; however, today they are considered two different diseases due to the neoplastic origin of the IMT. Our objective is to share our experience in the management of these two types of tumors that we must take into account in the differential diagnosis of pulmonary masses or nodules.

METHODS

Thirteen patients with a pathological diagnosis of IPT and IMT who underwent surgery between 2008 and 2019 were retrospectively studied. We recorded the pre and postoperative information of each one, as well as the survival analysis.

RESULTS

Of the 13 patients, 8 were men and 5 women. The mean age of presentation was 53,5 years. An atypical segmentectomy was performed in 6 patients; a lobectomy was necessary in 6 and a pneumonectomy in 1 case. In all cases a complete resection was achieved. Diagnosis was possible thanks to histology, immunohistochemical (IHQ) and fluorescent in situ hybridization (FISH) techniques determining the expression of IgG4 and the rearrangement of ALK, respectively. After a median follow up of 49 months, we didn't find any loco-regional or distant recurrence in the patients studied.

CONCLUSION

IPT and IMT are rare tumors with a very good prognostic. The diagnosis of both entities is based mainly on specific anatomopathological techniques. Surgery has, in most cases, both a diagnostic and therapeutic role.

Mass-forming immunoglobulin G4-related disease shows indolent clinical course after surgical resection, clinicopathological analysis of a series of 15 cases

The purpose of this study is to characterize the clinicopathological features of mass-forming immunoglobulin G4-related disease (IgG4-RD). A retrospective search for cases of mass-forming IgG4-RD diagnosed at Singapore General Hospital between 2008 and 2019 was performed. A total of 15 cases of mass-forming IgG4-RD were identified. The male-to-female ratio was 2.5:1, and the median age was 61 years old. The majority of cases showed a solitary lesion (12/15) with a mean size of 35 mm. IgG4-RD was considered as a clinical differential diagnosis only in one case (1/15) prior to the surgical resection. Diagnostic histopathological features, such as dense lymphoplasmacytic infiltrate positive for IgG4 plasma cells (15/15), storiform fibrosis (15/15), and obliterative phlebitis (9/15), were observed in most cases. These findings were distributed heterogeneously within the lesions. Cases with single organ involvement showed a low relapse rate (2/10) and normal serum IgG4 level after surgical resection. Mass-forming IgG4-RD has a male predilection and involves various organ systems. It may be initially misdiagnosed as malignancy and undergo surgical resection. The diagnostic histological features of IgG4-RD are readily identified in different organs. However, they may be distributed heterogeneously within a single lesion. Cases of single organ involvement show an indolent clinical course and normal serum IgG4 level after surgical resection.

Inflammatory pseudotumor and myofibroblastic inflammatory tumor. Diagnostic criteria and prognostic differences

INTRODUCTION

Inflammatory pseudotumor (IPT) and inflammatory myofibroblastic tumor (IMT) are two very rare entities that were formerly included in the same category; however, today they are considered two different diseases due to the neoplastic origin of the IMT. Our objective is to share our experience in the management of these two types of tumors that we must take into account in the differential diagnosis of pulmonary masses or nodules.

METHODS

Thirteen patients with a pathological diagnosis of IPT and IMT who underwent surgery between 2008 and 2019 were retrospectively studied. We recorded the pre and postoperative information of each one, as well as the survival analysis.

RESULTS

Of the 13 patients, 8 were men and 5 women. The mean age of presentation was 53,5 years. An atypical segmentectomy was performed in 6 patients; a lobectomy was necessary in 6 and a pneumonectomy in 1 case. In all cases a complete resection was achieved. Diagnosis was possible thanks to histology, immunohistochemical (IHQ) and fluorescent in situ hybridization (FISH) techniques determining the expression of IgG4 and the rearrangement of ALK, respectively. After a median follow up of 49 months, we didńt find any loco-regional or distant recurrence in the patients studied.

CONCLUSION

IPT and IMT are rare tumors with a very good prognostic. The diagnosis of both entities is based mainly on specific anatomopathological techniques. Surgery has, in most cases, both a diagnostic and therapeutic role.

A Rare Case of Inflammatory Myofibroblastic Tumor Causing Left Pulmonary Artery Stenosis and Successfully Treated with Localized Radiotherapy in a Patient with Perinuclear Antineutrophil Cytoplasmic Antibody Vasculitis

Inflammatory myofibroblastic tumor (IMT) of the lung is a rare neoplasm that commonly behaves in an indolent fashion and is generally treated with complete surgical excision. The management of unresectable IMT presents a significant challenge, especially in cases with multiple comorbidities, and a consensus has yet to be reached on the most appropriate first-line modality. We present a case of unresectable IMT causing severe stenosis of the left pulmonary artery in a patient on immunosuppressive therapy for perinuclear antineutrophil cytoplasmic antibody vasculitis. The patient was successfully treated with localized radiotherapy to a total dose of 45 Gy in five weeks, and has been followed for more than seven years since treatment. In this case report, we review the pertinent literature and illustrate the difficulties in diagnosing and treating rare neoplasms in a patient with significant medical comorbidities.

Morphologic Overlap Between Inflammatory Myofibroblastic Tumor and IgG4-related Disease: Lessons From Next-generation Sequencing

Inflammatory myofibroblastic tumor (IMT), a locally aggressive neoplasm capable of metastasis, may show an immunoglobulin (Ig)G4-rich lymphoplasmacytic infiltrate. Prior reports suggest that storiform-fibrosis and obliterative phlebitis aid in the distinction of IMT from IgG4-related diseases. Herein, we highlight the morphologic overlap between the 2 diseases, and emphasize the importance of a multiplex fusion assay in the distinction of IgG4-related disease (IgG4-RD) from IMT. We identified 7 IMTs with morphologic and immunohistochemical features of IgG4-RD; 3 patients were originally diagnosed with IgG4-RD. Demographic, clinical and morphologic data was recorded. We also reevaluated 56 patients with IgG4-RD. We performed immunohistochemistry for IgG4, IgG, ALK, and ROS1. In situ hybridization for IgG4 and IgG was performed in selected cases. A multiplex next-generation sequencing-based RNA assay for gene fusions was performed to detect all known IMT-related gene fusions. All 7 IMTs showed a dense lymphoplasmacytic infiltrate and storiform-type fibrosis, with obliterative phlebitis noted in 3 cases. The neoplastic stromal cells constituted <5% of overall cellularity and stromal atypia was either absent or focal and mild. Elevated numbers of IgG4 positive cells and increased IgG4 to IgG ratio was identified in all cases. Four cases showed ALK related abnormalities: 3 fusions and one alternative transcription initiation; while 2 patients showed ROS1 and NTRK3 fusions. One tumor was negative for known IMT-related gene fusions. All 56 IgG4-RD cases were negative for ALK and ROS1 on immunohistochemistry; 6 cases were negative on the fusion assay. Highly inflamed IMTs are indistinguishable from IgG4-RD both histologically and on immunohistochemistry for IgG4. We advocate scrutinizing patients with presumptive single organ IgG4-RD for IMT and the diagnostic algorithm should include ALK and ROS1 immunohistochemistry and, in selected cases, a next-generation sequencing-based fusion assay that covers known IMT-associated gene fusions.

Anaplastic lymphoma kinase-negative pulmonary inflammatory myofibroblastic tumor with multiple metastases and its treatment by Apatinib: A case report

RATIONALE

Primary pulmonary inflammatory myofibroblastic tumor (IMT) with distant metastasis is extremely rare. Moreover, metastasis of pulmonary IMT to bone marrow has never been reported in previous studies. Therapeutic approaches for anaplastic lymphoma kinase (ALK)-negative pulmonary IMT with metastasis are limited. Yet there is no report on the treatment of advanced IMT cases with anti-angiogenesis drugs.

PATIENT CONCERNS

We described a patient with a complaint of fatigue, with the chest computed tomography (CT) scan revealing 2 masses in bilateral lung.

DIAGNOSES

The CT-guided lung biopsy examined 1 lesion in the right lung, and the post-operative pathological diagnosis of ALK-negative pulmonary IMT was recommended. However, the lung lesions were found significantly enlarged during the subsequent visit 8 months later, along with multiple metastases to the bone and abdominal cavity. A bone marrow biopsy revealed bone marrow infiltration by spindle cells.

INTERVENTIONS

The patient began to take Celecoxib due to the rapid progression of IMT, however, resulting in the aggravated gastric ulcer. He stopped taking the medicine 1 month later, with no remarkable change in the lesions by CT. Apatinib was administrated instead of Celecoxib.

OUTCOMES

After the 5-month treatment of Apatinib, the mass in the abdominal cavity significantly shrank and the lung lesions slightly decreased in size. With the 9-month administration of Apatinib, the lung lesions and the abdominal mass kept stable, compared with the situation in the 5-month follow-up.

LESSONS

Although pulmonary IMT shows the potential of metastasis, its metastasizing to bone marrow is a highly unusual event. Apatinib is effective for pulmonary IMT, and should be taken into consideration for the treatment of inoperable pulmonary IMT patients who lack ALK rearrangement.

Surgical resection of pulmonary inflammatory pseudotumors: long-term outcome

Background Pulmonary inflammatory pseudotumors are rare lesions that remain problematic in several aspects, especially regarding the therapeutic strategy. The goal of this study was to evaluate long-term survival in a multicenter series of patients who required surgery for pulmonary inflammatory pseudotumors. Methods Thirty-six cases of pulmonary inflammatory pseudotumors, operated on in 3 French thoracic surgery departments between 1989 and 2015, were studied retrospectively. We recorded pre-, peri- and postoperative data for each patient, and long-term survival was analyzed. Results There were 22 men and 14 women. Mean age was 53.5 years (range 14-81 years). Three pneumonectomies, 1 bilobectomy, 19 lobectomies, 2 segmentectomies, 10 wedge resections, and 1 biopsy were performed. Complete resection was carried out in 32 (88.8%) patients. Median follow-up was 76 months. Five-year and 10-year survival rates were respectively 86.8% and 81.7% (96% and 90% for patients with R0 resection). Conclusions Long-term survival was excellent for patients with pulmonary inflammatory pseudotumors who benefited from surgery, especially when surgical resection was complete. These results confirm that surgical resection must be proposed as the first-line treatment for patients with pulmonary inflammatory pseudotumors.

A Comparative Study of Inflammatory Myofibroblastic Tumors and Tumefactive IgG4-related Inflammatory Lesions: the Relevance of IgG4 Plasma Cells

IgG4-related disease is a recently recognized systemic condition characterized by tumefactive lesions at various sites. Inflammatory pseudotumor (IPT), a tumefactive mass lesion with an unknown etiology, belongs to the spectrum of IgG4-related disease. Inflammatory myofibroblastic tumor (IMT), previously considered under the umbrella of IPT, is now classified as a clonal neoplasm. Previously, both the terms were used interchangeably, because of overlapping morphologic features. This study was carried out to compare the morphologic and the immunohistochemical features of these entities and to study the role of IgG4 in their pathogenesis. Thirty-nine cases comprising of IMT (n=18) and IPT (n=21) were retrieved, and their clinical, morphologic, and immunohistochemical features were studied. IMT was more common in children as compared with IPT. IMT cases showed the proliferation of myofibroblastic cells accompanied by a variable inflammatory infiltrate, whereas IPT cases showed predominantly stromal fibrosis and a lymphoplasmacytic infiltrate with a subset of cases showing a storiform fibrosis and obliterative phlebitis. Anaplastic lymphoma kinase-1 (ALK-1) was positive in 12 of the 18 (66.7%) IMT cases, whereas none of the IPT cases showed ALK-1 immunoreactivity. IPT cases showed significantly increased IgG4+ plasma cells (mean, 127.8/high-power fields vs. 17.8/high-power fields) and a higher IgG4/IgG ratio (mean, 48.2% vs. 10.7%) as compared with IMT. Fluorescence in situ hybridization analysis was positive for ALK rearrangement in 6 of the 9 IMT cases tested. In conclusion, most of the IPT cases can be considered as IgG4 related on the basis of their histopathologic features and immunohistochemistry criteria. However, IMT represents a myofibroblastic neoplasm with ALK-1 overexpression and is clearly not IgG4 related.

Immunoglobulin G4-related epidural inflammatory pseudotumor presenting with pulmonary complications and spinal cord compression: case report

Immunoglobulin G4-related disease (IgG4-RD) is a recently defined condition characterized by inflammatory tumefactive lesions in various organ systems. IgG4-RD is a clinical and radiological diagnosis of exclusion and requires the presence of specific histopathological criteria for diagnosis. A 50-year-old man presented to an outside hospital with a 3-month history of progressively worsening back pain and symptoms of pleurisy, nasal crusting, and hematochezia. Radiological workup revealed an epidural-paraspinal mass with displacement of the spinal cord, destruction of the T5-6 vertebrae, and extension into the right lung. Biopsy sampling and subsequent histopathological analysis revealed dense lymphoplasmacytic infiltrate with an increased number of IgG4-positive plasma cells and a storiform pattern of fibrosis. With strong histopathological evidence of IgG4-RD, the patient was started on a regimen of prednisone. Further testing ruled out malignant neoplasm, infectious etiologies, and other autoimmune diseases. Two weeks later, the patient presented with acute-onset paraplegia due to spinal cord compression. The patient underwent decompression laminectomy of T5-6, posterior instrumented fusion of T2-8, and debulking of the epidural-paraspinal mass. After the continued administration of glucocorticosteroids, the patient improved remarkably to near-normal strength in the lower extremities and sensory function 6 months after surgery. To the authors' knowledge, this is the first case of IgG4-related epidural inflammatory pseudotumor and spinal cord compression in the United States. This case highlights the importance of early administration of glucocorticosteroids, which were essential to preventing further progression and preventing relapse. IgG4-RD evaluation is important after other diseases in the differential diagnosis are ruled out.

Pulmonary inflammatory myofibroblastic tumor versus IgG4-related inflammatory pseudotumor: differential diagnosis based on a case series

BACKGROUND

Pulmonary inflammatory myofibroblastic tumor (IMT) has been considered as a synonym for inflammatory pseudotumor (IPT) for a long time. Recent studies have indicated that IMT and IgG4-related IPT are distinct diseases. However, no consensus criteria have been recommended. Here we propose a set of criteria for the differential diagnosis.

METHODS

Twenty-six archived IMT and IgG4-related IPT samples were examined for histological characteristics and the expression of IgG, IgG4, SMA and ALK-1. Based on our proposed criteria, we reclassified the cases into either IMT or IgG4-related IPT group and compared the clinicopathological features, laboratory findings, overall survivals (OS) and disease-free survivals between groups to validate the effectiveness and dependability of the diagnostic criteria.

RESULTS

The average age of IgG4-related IPT group was higher than IMTs (48.82 vs. 39.22 years, P=0.031). In IMT group, tumors were characterized by bigger tumor sizes (3.47 vs. 2.22 cm, P=0.007), diffuse and total destroyed alveoli (88.89% vs. 17.65%, P=0.002), fewer lymphoid follicles (1.6/HPF vs. 3.0/HPF, P=0.045) and lower expression of IgG (74.7/HPF vs. 149.1/HPF; P<0.001). As an exclusion criterion of IgG4-related IPT, ALK-positivity was correlated with the higher cytological atypia (mean 3.7/HPF, P<0.001) and lesser lymphoid follicles (mean 1.2/HPF, P=0.021). And it's the first study to show the liner positive correlation between the lymphocytes + plasma cells count and IgG4-positive plasma cells count in these lesions (r=0.914, P<0.001). The negative correlation between the IgG4-positive plasma cells count and the expression of ALK-1 are reported for the first time as well (rs=-0.632, P=0.001). However, despite two patients with recurrence or metastasis were divided into IMT group, only borderline values were detected in the survival analysis (OS 88.89% vs. 100%, P=0.197, DFS 77.78% vs. 100.00%; P=0.056).

CONCLUSIONS

The significant differences of clinicopathological characteristics between the IMTs and IgG4-related IPTs indicated that a combination of lymphocytes + plasma cells count, cytological atypia, IgG4 and ALK-1 staining will be helpful in differential diagnosis.

Indolent lung opacity: Ten years follow-up of pulmonary inflammatory pseudo-tumor

Inflammatory pseudotumor (IPT) has always been considered a diagnostic challenge. Its rarity and resemblance to other more common pathological entities imposes that neither clinical nor radiological characteristics can lead to a definitive diagnosis. The surgical excision of the lesion is the ultimate approach for accurate diagnosis and cure. Moreover the true nature of IPT, its origin as a neoplastic entity or an over-reactive inflammatory reaction to an unknown trigger, has been a long debated matter. Surgery remains the treatment of choice. IPT is mostly an indolent disease with minimal morbidity and mortality. Local invasion and metastasis predict a poor prognosis. We hereby present a unique case of pulmonary IPT that was surgically excised, but recurred contralaterally, shortly thereafter. Despite no medical or surgical treatment for ten years, the lesion has remained stable in size, with neither symptoms nor extra-pulmonary manifestations.

Clinico-radiological and Pathological Characteristics of Inflammatory Myofibroblastic Tumors in Children: A Retrospective Study

Purpose

Inflammatory myofibroblastic tumors (IMTs) are rare, benign lesions most often seen in the lung of young adults but can occur in children, in various sites. They mimic, clinically and radiologically, malignant tumors - especially sarcomas and lymphomas. The aim was to review the clinical, radiological, and pathological data of children with a diagnosis of IMT referred to our department.

Materials and Methods

This retrospective study was conducted at the Department of Medical and Paediatric Oncology, Regional Cancer Centre, Sher-I-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, India from January 2014 to December 2015.

Results

Among 288 pediatric tumors registered during the study, 5 (1.73%) had the diagnosis of IMTs. The main symptoms were abdominal distension and pain in 60% (three cases), breathlessness and cough in 20% (one case), and right axillary area swelling in 20% (one case). In three patients, complete surgical excision was done, whereas another patient with retroperitoneal mass had the residual disease and received chemotherapy followed by complete second surgery. In the case of mediastinal IMT, surgery was followed by local radiotherapy. At present, four patients are disease-free and one patient with mediastinal IMT has the residual progressive disease.

Conclusion

On presentation, IMT can constitute a formidable challenge, from diagnosis through to treatment.

IgG4-related inflammatory pseudotumor: A systematic review of histopathological features of reported cases

OBJECTIVES

There is marked inconsistency in reporting the key features of IgG4-related inflammatory pseudotumor (IPT) cases. We aimed to analyze the various aspects of IgG4-related IPTs and to test the performance of the consensus criteria for their diagnosis.

METHODS

PubMed database was searched for IgG4-related IPT cases. The data regarding patient demographics, clinical presentation, laboratory findings, histopathological features, and treatment response are extracted and are presented here in a descriptive manner.

RESULTS

The study included 40 papers describing the clinicopathological features of 83 IPTs in 80 patients. Seventeen cases were diagnosed on biopsies; while remaining were diagnosed on excision specimens. Among these, 50 cases were categorized as highly suggestive and 24 cases as probable for IgG4RD; while nine cases had insufficient histopathological evidence of IgG4RD. Two cases diagnosed on biopsies having insufficient evidence of IgG4RD showed partial or no response to steroids; while 12/14 cases (85.71%) diagnosed on biopsies that were histologically suggestive or probable for IgG4RD showed prompt response to steroids.

CONCLUSION

Many reports have not specifically mentioned the full histopathological findings of IgG4-related IPTs that may hinder in refining the diagnostic criteria of IgG4RD. The IgG4-related IPTs diagnosed on biopsies with requisite features showed prompt response to steroids indicating specificity of histopathological findings in predicting treatment response.

[Immunoglobulin G4-related lung disease: Case report and literature review]

We report the case of a 61-year-old man with a pulmonary nodule discovered while staging the metastasis of a squamous cell carcinoma. No primary cancer was found. Histological examination of the resected specimen (lingula) was in favor of IgG4-related inflammatory pseudotumor. Histological criteria were described in 2012, combining a dense lymphoplasmacitic infiltrate rich in IgG4-positive plasma cell, storiform fibrosis and obliterative phlebitis. IgG4/IgG plama cell ratio>40 % is mandatory for histological diagnosis of IgG4-related disease. This is a rare and often underdiagnosed disease. Diagnostic criteria are now defined and consensual, combining clinical signs, biology and histology.

Inflammatory myofibroblastic tumor of the lung in pregnancy mimicking carcinoid tumor

Inflammatory myofibroblastic tumors (IMT) are uncommon neoplasms of the lung in adults. They constitute less than 1% of all lung neoplasms and usually present as parenchymal masses. Diagnosis requires a high index of suspicion. They are characterized by spindle-shaped tumor cells (fibroblasts/myofibroblasts) in a background of lymphoplasmacytic infiltrate. About 50% of the tumors harbor an ALK gene rearrangement. They have to be differentiated from inflammatory pseudotumors (IPT), which show increased number of IgG4 plasma cells on immunostaining and are negative for anaplastic lymphoma kinase (ALK) protein. Herein, we present a case of a 28-year old female who presented with hemoptysis and was diagnosed with an IMT of lung in the first trimester of pregnancy. We have not only reviewed the occurrence of IMT during pregnancy but also discuss the management options for IMT during pregnancy.

Remission of ALK-negative primary pulmonary inflammatory myofibroblastic tumor on treatment with clarithromycin: A case report and review of the literature

Inflammatory myofibroblastic tumors (IMTs) belong to an intermediate group of soft-tissue tumors, they are relatively rare but exhibit a wide range of pathologies, from benign to malignant. At present, no standard treatment has been established, however, it is known to be important to determine the grade of malignancy of the tumor, prior to treatment. The present study reports a 73-year-old female patient with no clinical manifestations, who, when examined radiographically at a health check exhibited bilateral thoracic infiltrative shadows and nodular shadows by chest CT. A metastatic tumor or an organizing pneumonia were suspected. Blood examination showed no abnormal findings, and a pathological diagnosis of IMT was given from the histological findings of the tissue extracted by video-assisted thoracic surgery. Histological analysis established the lack of expression of anaplastic lymphoma kinase (ALK1) and immunoglobulin subtype G4 (IgG4). Alteration of the radiological shadows was observed over several weeks, and after concluding that chronic inflammation was worsening the patient's condition, clarithromycin was administered as a long-term macrolide therapy. The IMT decreased in size, and eight months later it had almost resolved. The patient was last reported to be maintaining a stable condition with no relapse. Some IMT cases have malignant pathology, and should be carefully followed-up. However, in the present case, where the IMT is both ALK1-negative and IgG4-negative, its biological immune responsiveness appears to differ from positive cases, and an inflammatory response was predominant. Clarithromycin, has immunomodulatory and anti-inflammatory effects and appeared to be effective in treating the IMT of the patient in the present study.

Inflammatory Pseudotumor (IPT) and Inflammatory Myofibroblastic Tumor (IMT): A Representative Literature Review Occasioned by a Rare IMT of the Transverse Colon in a 9-year-old Child

Aims and Background

Inflammatory pseudotumor (IPT) and inflammatory myofibroblastic tumor (IMT) represent different entities. However, it is only in recent years that this has been taken into increasing consideration. Some authors still use both terms synonymously or interchangeably. Inflammatory myofibroblastic tumor is a real neoplasm because of the proliferation of myofibroblastic cells. Inflammatory pseudotumor is a more inflammatory reactive or regenerative entity and shows an overlapping with immunoglobulin G4-related disease.

Methods and Study Design

To analyze the current situation, 443 publications from the last 5 years (2009 to February 2014) were included. Reports involved 938 patients and 956 organ sites. The age distribution is twin peaked with one maximum in childhood and the other between 50 and 60 years of age. This distribution is questionable due to the more frequent occurrence of IPT in the liver and of IMT in the lung. Inflammatory pseudotumors mainly occur in older patients; IMTs in children and young adults.

Results and Conclusions

The liver and biliary tract were the most commonly affected of all body regions, at 32%. This was followed by the lung, including the respiratory tract, at 27%, and by the gastrointestinal tract, at 10%. Lesions of the large bowel, as in the present case of a 9-year-old boy, are very rare. There were organ-related as well as nonspecific clinical symptoms, such as fever, weight loss, and fatigue. Laboratory test results revealed anemia and elevated inflammation-dependent parameters. The patterns in medical imaging are variable and nonspecific. Morphology often suggests a malignant process. For this reason, therapy in most cases is surgical, but this is required more often in IMTs. Many IPTs could be treated conservatively.

Current management of pediatric soft tissue sarcomas

Pediatric soft tissue sarcomas are a group of malignant neoplasms arising within embryonic mesenchymal tissues during the process of differentiation into muscle, fascia and fat. The tumors have a biphasic peak for age of incidence. Rhabdomyosarcoma (RMS) is diagnosed more frequently in younger children, whereas adult-type non-RMS soft tissue sarcoma is predominately observed in adolescents. The latter group comprises a variety of rare tumors for which diagnosis can be difficult and typically requires special studies, including immunohistochemistry and molecular genetic analysis. Current management for the majority of pediatric sarcomas is based on the data from large multi-institutional trials, which has led to great improvements in outcomes over recent decades. Although surgery remains the mainstay of treatment, the curative aim cannot be achieved without adjuvant treatment. Pre-treatment staging and risk classification are of prime importance in selecting an effective treatment protocol. Tumor resectability, the response to induction chemotherapy, and radiation generally determine the risk-group, and these factors are functions of tumor site, size and biology. Surgery provides the best choice of local control of small resectable tumors in a favorable site. Radiation therapy is added when surgery leaves residual disease or there is evidence of regional spread. Chemotherapy aims to reduce the risk of relapse and improve overall survival. In addition, upfront chemotherapy reduces the aggressiveness of the required surgery and helps preserve organ function in a number of cases. Long-term survival in low-risk sarcomas is feasible, and the intensity of treatment can be reduced. In high-risk sarcoma, current research is allowing more effective disease control.

Inflammatory myofibroblastic tumor of the trachea in the pediatric age group: case report and systematic review of the literature

Inflammatory myofibroblastic tumors are uncommon tumors, which present as solitary masses in the pulmonary parenchyma. Tracheal involvement by these tumors is extremely rare and can be misdiagnosed as asthma. The closest histologic differential diagnoses are IgG4-related sclerosing pseudotumors, which are differentiated by IgG4 positivity. Fifty percent of inflammatory myofibroblastic tumors are positive for anaplastic lymphoma kinase gene rearrangements. The treatment modality of choice is surgical resection with therapeutic bronchoscopy reserved for patients presenting with acute airway obstruction or in those unwilling for surgery. New and upcoming treatments include anaplastic lymphoma kinase inhibitors like crizotinib.

IgG4 related sclerosing mastitis: expanding the morphological spectrum of IgG4 related diseases

IgG4 related disease (IgG4RD) is a recently recognised condition characterised by mass forming lesions associated with storiform fibrosis, obliterative phlebitis, lymphoplasmacytic infiltrate rich in IgG4 positive plasma cells and elevated serum IgG4 levels. Although rare, mammary involvement has been reported as IgG4 related sclerosing mastitis, the morphological counterpart of a growing family of IgG4 related diseases. A total of 17 cases belonging to mass forming benign inflammatory breast lesions such as plasma cell mastitis, granulomatous lobular mastitis, non-specific mastitis and inflammatory pseudotumour were investigated as a possible member of IgG4 related sclerosing mastitis. Clinical, radiological, histopathological and immunohistochemistry findings were noted in all cases. Cases diagnosed as inflammatory pseudotumour showed all the histopathological features of IgG4RD along with increased number of IgG4 positive plasma cells and IgG4/IgG ratio >40%. However, only a few IgG4 positive cells were seen in plasma cell mastitis, granulomatous lobular mastitis and non-specific mastitis cases. These cases also did not fulfill the morphological criteria for the diagnosis of IgG4 related diseases. IgG4RD should be excluded in plasma cell rich lesions diagnosed on core biopsies by IgG4 immunostaining. This can avoid unnecessary surgery as IgG4 related diseases respond to simple and effective steroid treatment.

Inoperable inflammatory myofibroblastic tumour of the para-nasal sinuses and orbit with recurrence responding to methotrexate and prednisolone: a case report

BACKGROUND

Inflammatory myofibroblastic tumour is a rare neoplasm with a potential to behave in a malignant manner. It can occur anywhere in the body, however involvement of the head, especially the para-nasal sinuses is rare.

CASE PRESENTATION

A 33-year-old South Asian male presented with coryzal symptoms including a persistent cough with an asymmetrical swelling of the left side of the face. Imaging revealed a mass lesion involving the para-nasal sinuses eroding into the orbit. Histology and the clinical picture were compatible with inflammatory myofibroblastic tumour. As curative excision of the tumour was not feasible, medical management was offered. Despite early features of remission to glucocorticoids, tapering resulted in recurrence. Hence combination therapy with glucocorticoids and methotrexate was commenced with dramatic reduction of tumour burden and the patient has been in remission to date.

CONCLUSION

Inflammatory myofibroblastic tumour has the potential to behave in a malignant manner. Medical management with chemotherapy, glucocorticoids and non-steroidal anti-inflammatory drugs though effective, do not have a uniform response pattern. Surgically unresectable inflammatory myofibroblastic tumour above neck should be treated aggressively with combination regimens. Combination of prednisolone with methotrexate has been shown to have good outcome.

Hepatic inflammatory myofibroblastic tumors: Analysis of 24 cases

AIM: To investigate the clinical characteristics, diagnosis and treatment of hepatic inflammatory myofibroblastic tumors (HIMTs).

METHODS: Clinical data for 24 patients with HIMT who were treated at Guangxi Tumor Hospital during the recent 10 years were analyzed retrospectively.

RESULTS: The cause of HIMT is still unclear now. Right upper abdomen pain and fever are common symptoms. Preoperative laboratory examinations showed that alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and cancer antigen 125 (CA125) were normal. HBsAg positivity was found only in 11 patients. In dynamic enhanced computed tomography (CT) or magnetic resonance imaging (MRI) scans, most tumor lesions demonstrated peripheral enhancement or septal enhancement during the delayed phase. Pathological examination showed fusiform cells arranged in fascicles in the collagen matrix with lymphocytes and plasma cells infiltrating. Immunohistochemistry showed that the spindle cells expressed Vimentin (8/8) and smooth muscle actin (8/8). Fifteen cases underwent complete tumor resection, and 9 cases only underwent biopsy. The median follow-up duration was 46 months. Five patients were lost during follow-up, and 19 patients are still alive.

CONCLUSION: HIMTs have nonspecific clinical manifestations. Dynamic enhanced CT or MRI can reveal their histopathologic characteristics and be of great value in diagnosis. Surgical resection is recommended when the diagnosis is in doubt or if a malignant tumor cannot be excluded.