Inflammatory myofibroblastic tumor of the lung in children: anaplastic lymphoma kinase (ALK) expression and clinico-pathological correlation

Treatment and outcomes in pediatric inflammatory myofibroblastic tumors - A systematic review of published studies

Inflammatory myofibroblastic tumor (IMT) is a soft tissue neoplasm which can be locally invasive, recur, or in rare cases metastasize. Often originating from the abdomen or thorax, IMT most commonly affects children and young adults. Due to its rarity comprehensive reports detailing clinical management and outcome(s) are sparse and often based on limited index case numbers. This study systematically analyzes outcome metrics of pediatric IMT and identifies risk factors for mortality. Medline/Embase databases were searched in accordance with PRISMA guidelines. Final analysis included 57 studies with 673 IMT patients (355 males, 53 %). Individual patient data was available for 405 cases with a median follow-up period of 36 months. Tumor sites included abdomen/pelvis (n = 233, 58 %), thorax (n = 125, 31 %), head/neck (n = 34, 8 %), and extremities (n = 13, 3 %). Surgical tumor resection was the mainstay of treatment, while only 20 patients (5 %) were treated non-operatively. Recurrence(s) were reported in 80 patients (20 %) with 34 (12 %) requiring reoperation. Positive tumor margins were a significant risk factor for tumor recurrence (p < 0.0001). Chemo/radiotherapy was reported in 98 patients (25 %). Most patients (94 %) survived; 81 % (n = 237) with no evidence of recurrent disease, 14 % (n = 41) were alive with disease, and 25 (6 %) died of disease. Positive margins at primary operation, and metastatic disease were associated with mortality (p < 0.0001 for both). IMT is a rare tumor with favorable outcome for the majority of patients. Whilst most patients will present with benign tumors, complete surgical resection (R0) is crucial, as positive surgical margins are a significant risk factor for tumor recurrence and mortality.

Crizotinib combined with bronchoscopic interventional treatment in ALK-positive inflammatory myofibroblastic tumor of left main stem bronchus: a case report

BACKGROUND

Inflammatory myofibroblastic tumor (IMT), also known as an inflammatory pseudotumor, is a unique type of intermediate soft tissue tumor that commonly occurred in the lung. Its unclear etiology and cellular activity brought about the confusion not only in naming of it, but also in diagnosis and treatment.

CASE PRESENTATION

We reported the case of an 18-year-old male student who suffered from shortness of breath, chest tightness and chest pain. Chest computed tomography scan showed a spherical neoplasm blocking left main stem bronchus. After fiberoptic bronchoscopy procedure, the results of histopathological and immunohistochemical analysis indicated an IMT. The targeted next generation sequencing based genomic profiling of the tumor using formalin-fixed and paraffin embedded tissue was performed and a EML4-ALK fusion was detected. The patient began to receive Crizotinib, a ALK tyrosine kinase inhibitor, at a dose of 250 mg twice daily orally. The patient has recovered well after the operation, and no recurrence or metastasis has been found after 12 months' follow-up.

CONCLUSION

By means of the diagnosis and treatment of this case, the characteristics and therapies of IMT are illustrated. In addition, it also provides a reference for the therapeutic strategy of IMT in the future.

Fetal Lung Interstitial Tumor (FLIT): Review of The Literature

Fetal lung interstitial tumor (FLIT) is an extremely rare pediatric lung tumor that shares radiological features with congenital pulmonary malformations (cPAM) and other lung neoplasms. A review of the literature, together with the first European case, are herein reported. A systematic and manual search of the literature using the keyword "fetal lung interstitial tumor" was conducted on PUBMED, Scopus, and SCIE (Web of Science). Following the PRISMA guidelines, 12 articles were retrieved which describe a total of 21 cases of FLIT, and a new European case is presented. A prenatal diagnosis was reported in only 3 out of 22 (13%) cases. The mean age at surgery was 31 days of life (1-150); a lobectomy was performed in most of the cases. No complications or recurrence of disease were reported at a mean follow-up of 49 months. FLIT is rarely diagnosed during pregnancy, may present at birth with different levels of respiratory distress, and requires prompt surgical resection. Histology and immunohistochemistry allow for the differentiation of FLIT from cPAM and other lung tumors with poor prognosis, such as pleuropulmonary blastoma, congenital peri-bronchial myofibroblastic tumor, inflammatory myofibroblastic tumor, and congenital or infantile fibrosarcoma.

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.

Inflammatory Myofibroblastic Tumor of the Upper Airways Harboring a New TRAF3-ALK Fusion Transcript

Inflammatory myofibroblastic tumor (IMT) is a rare disease that mainly involves the lung and the abdomen with an intermediate clinical course but a recurrence rate between 15–30%. Radical surgery represents the gold standard of treatment, while chemotherapy and radiotherapy are considered for unresectable lesions. The identification of ALK translocations in IMT opened the option for the use of target therapies. Indeed, the ALK inhibitors have changed the treatment approach for aggressive lesions, improving the prognosis. Intraluminal upper-way IMT is extremely rare and represents a medical challenge. We reported an endotracheal IMT case presenting a previously unknown TRAF3-ALK fusion transcript.

Inflammatory myofibroblastic tumours of the thorax: Radiologic and clinicopathological correlation

CONTEXT AND AIMS

Inflammatory myofibroblastic tumour (IMT) is a rare mesenchymal neoplasm with intermediate malignant potential. The aim of this study is to describe and compare the clinical presentation, computed tomography (CT) findings and anaplastic lymphoma kinase -1 (ALK-1) expression of IMT of the thorax in children and adults. We also sought to study the tumour behaviour after treatment on the follow-up imaging.

MATERIALS AND METHOD

This is a retrospective observational study of 22 histopathologically proven cases of IMT in the thorax. The clinical parameters, CT findings, biopsy results, treatment received and follow-up were recorded. Statistical analysis was performed using Fisher's exact test.

RESULTS

IMT of the thorax had diverse imaging appearances, presenting either as large invasive lung masses with or without calcifications or as smaller endobronchial lesions. Children commonly presented with long duration fever (P = 0.02) and large invasive lung masses (P = 0.026), whereas adults presented with long duration haemoptysis (P = 0.001) and endobronchial lesions or smaller lung parenchymal lesions. Calcifications were more common in children (P = 0.007). ALK-1 was positive in 40% of children and 18.2% of adults (P = 0.547). Endobronchial lesions showed a trend for ALK-1 negativity. Patients with bronchoscopic excision had local recurrence and patients with surgical wedge resection had metastatic brain lesions as compared to those with lobectomy and pneumonectomy (P = 0.0152). A patient with unresectable lung mass had malignant transformation to spindle cell sarcoma after 9.5 years.

CONCLUSIONS

Thoracic IMT presents with some distinct clinical and CT findings in adults and children. The CT findings and management options have implications for prognosis. If resectable, lobectomy is a better option than wedge resection or bronchoscopic excision for preventing local recurrence and metastasis. IMT can undergo malignant transformation.

Spontaneous pneumothorax caused by an inflammatory myofibroblastic tumor-like lesion in a 14-year-old girl: a case report

Background

Spontaneous pneumothorax occurs more often in younger, slim, and shallow-chested men. Although less common, differential diagnoses for secondary pneumothorax in children are asthma, emphysematous blebs, catamenial pneumothorax, and others. We report a patient who presented with pneumothorax and was found to have an inflammatory myofibroblastic tumor (IMT)-like lesion, and present a review of the related literature.

Case presentation

A 14-year-old girl visited her physician for chest pain that developed while exercising. Although chest drainage was performed, the symptoms associated with a collapsed lung did not improve, and she was referred to our hospital. Computed tomography revealed the presence of a 19 × 17-mm cyst with a thick wall in the apex of the right lung. She was tested for infectious diseases, namely tuberculosis, but the results were not definitive. Catamenial pneumothorax was also suspected because she was menstruating when she presented to our hospital. As a therapeutic diagnosis, we performed a thoracoscopic partial resection of the right upper lobe of the lung. Three small openings were identified inside the cyst, suggesting connection with the bronchiole. The lesion was pathologically diagnosed as an IMT-like lesion. Considering the progress so far, we considered that the final diagnosis to be an IMT. The patient was discharged on postoperative day 3, and we have followed her for the past 6 months with no local recurrence or metastasis.

Conclusions

IMT is not uncommon in children. Therefore, this lesion should be considered as a possible diagnosis if children and young adults develop spontaneous pneumothorax.

Pulmonary Inflammatory Myofibroblastic Tumor in Children: A Case Report and Brief Review of Literature

The inflammatory myofibroblastic tumor (IMT) is a rare lesion of unclear etiology and variable clinical course, consisting of a proliferation of fibroblasts and myofibroblasts, mixed with inflammatory cells. Synonyms of IMT are inflammatory pseudotumor and plasma cell granuloma reflecting the alleged inflammatory nature attributed to this lesion, even though this heterogeneity in the disease denomination is probably involved in a dispersion of the literature data. Among primary pulmonary neoplasms, it represents the most frequent endobronchial tumor of childhood and beyond the lung it has been described mainly in the bladder, mediastinum and mesentery. Despite having a tendency for local recurrence, the risk of distant metastasis is low. Clinical presentation depends on localization therefore lung peripheral lesions are often asymptomatic resulting in a delayed diagnosis. Radiological findings can suggest the diagnosis that must be confirmed by histopathology assessment. The tumor has been characterized by the application of immunohistochemical techniques, molecular biology and cytogenetics, which are very precious for the diagnosis. The therapeutic approach consists in the complete surgical excision of the lesion that normally ensures excellent survival. Due to the potential risk of recurrence, close clinical trial is indicated. To date only 24 cases of pulmonary IMT have been described, although the prevalence is probably higher. We present a case report of a 3-year-old girl with pulmonary IMT and a brief review of known literature cases in order to highlight the most common clinical presentations, the most useful diagnostic tools and therapeutic approach.

Inflammatory myofibroblastic tumors of the lung carrying a chimeric A2M-ALK gene: report of 2 infantile cases and review of the differential diagnosis of infantile pulmonary lesions

We report 2 infantile cases of pulmonary tumor carrying a chimeric A2M-ALK gene. A2M-ALK is a newly identified anaplastic lymphoma kinase (ALK)-related chimeric gene from a tumor diagnosed as fetal lung interstitial tumor (FLIT). FLIT is a recently recognized infantile pulmonary lesion defined as a mass-like lesion that morphologically resembles the fetal lung. Grossly, FLIT characteristically appears as a well-circumscribed spongy mass, whereas the tumors in these patients were solid and firm. Histologically, the tumors showed intrapulmonary lesions composed of densely proliferating polygonal or spindle-shaped mesenchymal cells with diffuse and dense infiltrations of inflammatory cells forming microcystic or micropapillary structures lined by thyroid transcription factor 1-positive pneumocytes, favoring inflammatory myofibroblastic tumor rather than FLIT. The proliferating cells were immunoreactive for ALK, and A2M-ALK was identified in both tumors with reverse-transcription polymerase chain reaction. The dense infiltration of inflammatory cells, immunoreactivity for ALK, and identification of an ALK-related chimeric gene suggested a diagnosis of inflammatory myofibroblastic tumor. Histologically, most reported FLITs show sparse inflammatory infiltrates and a relatively low density of interstitial cells in the septa, although prominent infiltration of inflammatory cells and high cellularity of interstitial cells are seen in some FLITs. The present cases suggest that ALK rearrangements, including the chimeric A2M-ALK gene, may be present in these infantile pulmonary lesions, especially those with inflammatory cell infiltration. We propose that these infantile pulmonary lesions containing a chimeric A2M-ALK gene be categorized as a specific type of inflammatory myofibroblastic tumor that develops exclusively in neonates and infants.

Synchronous Inflammatory Myofibroblastic Tumor in Lung and Brain: A Case Report and Review of Literature

Inflammatory myofibroblastic tumor (IMT) is a rare entity and a diagnostic challenge with myriad clinical presentations and pathogenetic mechanisms. Isolated occurrences can be at any site in the body; however, only a few cases of IMT with the concomitant appearance of different organs have been published. We report a unique occurrence of bilateral inflammatory myofibroblastic tumor of the lungs with synchronous brain parenchymal lesions in an 11-year-old male, detailing clinical presentation with the emphasis on imaging and review of the literature.

Inflammatory myofibroblastic tumors in children

BACKGROUND

Inflammatory myofibroblastic tumor (IMFT) is an uncommon neoplasm in children.

METHODS

Retrospective review from 1993 to 2014 of patients ≤18years of age with a histopathologic diagnosis of IMFT treated at two tertiary centers.

RESULTS

Thirty-two patients were diagnosed with IMFT. Mean (±SD) age was 9.3±5.7years at diagnosis. Tumor location was variable: abdomen/pelvis (28%), head/neck region (22%), intrathoracic (22%), genitourinary (9%), bowel (6%) liver (6%), and musculoskeletal (6%). Median follow-up was 2.6±4.6years, with 3 recurrences and 2 deaths, which occurred only after recurrence. Positive microscopic margin after resection was associated with recurrence, compared to those that had a negative margin (40% vs. 0%, p=0.04). Recurrence was associated with increased mortality (67% vs 0%, p=0.01). Time from first symptoms to resection was shorter in those with recurrence (25.8±22 vs. 179±275days, p=0.01) and in nonsurvivors (44.0±8.0 vs. 194.3±53.4days, p=0.02). Adjuvant chemotherapy, not including steroid monotherapy, either given before or after resection, was administered more often to nonsurvivors (100% vs 4%, p=0.009), and use of corticosteroids was also higher in the nonsurvivors (100% vs. 15%, p=0.04).

CONCLUSIONS

IMFT is a rare pediatric neoplasm with variable locations. Complete excision is critical for cure. Proposed guidelines for diagnosis, treatment and surveillance of theses tumors in children are reported.

Pulmonary Myofibroblastic Tumour Involving the Pericardium and Left Atrium in an 18 Month Infant

Inflammatory myofibroblastic tumor (IMT) is the most frequent primary lung tumor in children and it may be locally aggressive. The management of a locally advanced pulmonary IMT in an 18 month-old female child is presented.A left pulmonary mass was incidentally found on the computerized tomography (CT) scan of a child with persistent systemic inflammatory syndrome. Biopsy confirmed the diagnosis; after preoperative corticotherapy, left pneumonectomy was performed. The pericardium and left atrium were invaded and resected, requiring pericardial reconstruction. There is no relapse at four years of follow-up.Steroids play a role in tumor size reduction, but marginal resection is the gold standard. Extended approaches are feasible and often required in advanced cases.