Inflammatory myofibroblastic tumor of the head and neck

Recurrent Inflammatory Myofibroblastic Tumor of Larynx Harboring a Novel THBS1::ALK Fusion

Inflammatory myofibroblastic tumor (IMT) is a rare soft tissue tumor primarily occurring in the abdominopelvic region of young patients, and it is characterized by spindle-shaped myofibroblasts, or fibroblasts surrounded by inflammatory infiltrate. Herein, we report a case of a 24-year-old male with a firm submucosal mass in the anterior right vocal fold diagnosed as an IMT that recurred 14 months later. The tumor demonstrated a novel THBS1::ALK fusion containing Exons 1-7 of the thrombospondin 1 (THBS1) gene fused to Exon 19 of the anaplastic lymphoma kinase (ALK) gene via next-generation sequencing with the NextSeq sequencer. The fusion of THBS1 to ALK potentially results in increased expression and constitutive activation of the ALK kinase domain. These findings not only broaden the repertoire of known ALK fusion partners implicated in tumorigenesis but also provide a novel avenue for investigating the etiology of recurrent IMT by considering this fusion event as a causal factor. To our knowledge, this is the second case of IMT of the larynx with this novel mutation reported in the literature and the first such case with a detailed description of this specific fusion and clinical recurrence.

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.

What do we know about inflammatory myofibroblastic tumors? - A systematic review

BACKGROUND

Inflammatory myofibroblastic tumors (IMTs) are rare intermediate-grade neoplasms that have a high recurrence rate after excision and exhibit low metastatic potential. These tumors contain proliferating neoplastic, fibroblastic and myofibroblastic cells, and are also characterized by chronic inflammatory infiltration by lymphocytes, plasma cells, eosinophils, and histiocytes. They belong to the group of inflammatory spindle cell lesions. Some reactive lesions, such as inflammatory pseudotumors, may appear to be IMTs, which makes their differential diagnosis extremely difficult. The aim of this article is to compile the recent information on IMTs to aid in their diagnosis and treatment.

METHODS

We reviewed articles published between 2017 and 2021, which were selected from online medical databases. In addition, some earlier articles and latest scientific monographies were analyzed.

RESULTS

The terminology used for inflammatory spindle cell lesions seems to be confusing. The terms "inflammatory myofibroblastic tumors" and "inflammatory pseudotumors" are interchangeably used by many scientists. However, a detailed analysis of the development of terminology suggests that the term "inflammatory myofibroblastic tumors" should be used to refer to a neoplastic lesion.

CONCLUSIONS

IMTs are rare neoplasms, which have not been investigated in detail due to the difficulty in collecting a large number of cases. Thus, our knowledge about this disease remains unsatisfactory. Recently developed techniques such as next-generation sequencing and computer-aided histopathological diagnosis may be useful in understanding the etiopathology of IMTs, which will help in the selection of the most appropriate therapy for patients.

Sinonasal inflammatory myofibroblastic tumour: a rare entity with diagnostic challenges

Inflammatory myofibroblastic tumour is a rare entity causing sinonasal involvement with variable behaviour. Mimicking various benign and malignant lesions, accurate diagnosis is often clinched on histopathology complemented with appropriate immunohistochemistry markers. Surgical resection is the main treatment modality with other forms of therapy reserved for unresectable lesions. We highlight a case of dual involvement of the sinonasal region and nasal bones along with the diagnostic and treatment challenges encountered. As the nasal bones were involved, surgical resection with negative margins required cosmetic reconstruction in the same sitting. A costochondral graft helped in achieving cosmetic pleasing results with no recurrence on follow-up.

Inflammatory Myofibroblastic Tumor of the Retroperitoneum Including Chronic Granulomatous Inflammation Suggesting Tuberculosis: A Case Report

An inflammatory myofibroblastic tumor (IMT) is a solid tumor of unknown etiology frequently affecting children and young adults and commonly affecting the lung or orbital region. We present a case involving a 41-year-old man who had an IMT combined with Mycobacterium tuberculosis infection in the retroperitoneum. He presented with only pain in the right lower abdomen without accompanying symptoms; a retroperitoneal mass was found on computed tomography. The tumor had invaded the end of the ileum and was attached to the omentum, so mass excision could not be performed. The tumor was completely excised surgically and had histological features diagnostic of an IMT. Histologic findings of the omentum were positive for Ziehl-Nielsen staining for acid-fast bacilli and for a positive polymerase chain reaction for M. tuberculosis. The patient had no apparent immune disorder. These findings made this case exceptional because IMTs, which are mostly due to atypical mycobacteria, have been found mainly in immunocompromised patients.

Buccal space tumours

OBJECTIVE

To review the available literature as it pertains to the buccal space with a specific focus on the pathologies encountered within this space. Clinical presentation, investigations, and surgical approaches to the region are also reviewed.

METHODS

A systematic review of the available literature was performed on buccal space tumours from 1980 to 2017. Data was extracted on clinical presentation, investigations and surgical approaches to the buccal space. The pathologies encountered in the buccal space were reviewed and presented.

RESULTS

Forty-nine unique articles were reviewed, with a total 217 patients. The age of the patients ranged from 0 to 83 with a mean age of 45.8. A total of 51 pathologies were reported. The majority of these were vascular and salivary gland pathologies. The majority of salivary gland neoplasms were malignant. However a wide variety of benign and malignant soft tissue tumours were also reported to occur in this region.

CONCLUSIONS

The buccal space is a small and complex region with a variety of pathologies occurring within it. This review clarifies the differential diagnosis of a mass which presents in this area and the pathologies which occur within it.

MRI characterization of inflammatory myofibroblastic tumors in the maxillofacial region

PURPOSE

We aimed to investigate the magnetic resonance imaging (MRI) appearance of inflammatory myofibroblastic tumors (IMTs) in the maxillofacial region in order to improve diagnostic quality and resection efficacy.

MATERIALS AND METHODS

Ten cases of pathologically identified IMTs were analyzed by MRI. The MRI features were examined, including tumor location, tumor shape, tumor margins, and involvement of the surrounding tissues.

RESULTS

Of ten masses investigated in this study, eight masses were irregular neoplasms with unclear margins and two masses, in the parotid gland, were regular neoplasms with clear margins. Precontrast T1-weighted images of all ten masses exhibited isointense signals compared to the adjacent tissue, while contrast-enhanced T1-weighted images showed strong enhancement. Six masses were hypointense and four masses were slightly hyperintense in T2-weighted images. Involvement of the adjacent structures was observed in eight of ten cases. Meanwhile, two patients experienced intracranial involvement.

CONCLUSION

IMTs are rare tumors in the maxillofacial region, displaying a number of distinct MRI characteristics. Most importantly, they display low T2 signal intensity and strong enhancement, and they frequently invade surrounding structures. Thus, MRI can improve the accuracy of IMT diagnoses and provide critical information for surgical planning.

A case report of an inflammatory myofibroblastic tumor of the neck: A focus on the computed tomography and magnetic resonance imaging findings

Inflammatory myofibroblastic tumors (IMTs) of the neck are rare, with only a few patients reported in the literature. The present study discusses the clinical manifestations, radiographic characteristics and management of these tumors, with a focus on imaging modalities. A case of IMT of the neck is presented and the associated literature is reviewed. In total, seven patients in seven English-language studies, including the present case, and one patient in one Chinese-language study were found. On CT scans, all tumors appeared as soft-tissue densities. Upon magnetic resonance imaging (MRI), all tumors displayed a heterogeneous hypointense-isointense signal on T1-weighted sequences and an isointense-hyperintense signal on T2-weighted sequences. All tumors showed enhancement on enhanced CT and MR images. The imaging features of the neck IMTs can be summarized as follows: i) When enhanced, the tumor displays enhancement on CT and MR images; ii) MRI is superior to CT scans in the differential diagnosis of this disease; iii) in general, the lesion displays a hypointense-isointense signal on T1-weighted sequences and an isointense-hyperintense signal on T2-weighted sequences; iv) due to the fibrous tissue in the tumor, delayed enhancement may be observed on gadolinium-enhanced MR images; and v) due to its benign or intermediate features, the tumor is usually a well-defined mass.

Inflammatory myofibroblastic tumors of the nasal cavity and paranasal sinus: a clinicopathologic study of 25 cases and review of the literature

Inflammatory myofibroblastic tumor (IMT) is rare in nasal cavity and paranasal sinus. The aim of this study was to describe the clinicopathological features of sinonasal IMT and analyze the relationship between the clinicopathological features and the prognosis. A retrospective study of 25 IMT patients between 2001 and 2012 was performed. Data on clinical features, treatment, and follow-up were recorded. The histological characters were observed. Overall survival (OS) and event-free survival (EFS) were estimated using the Kaplan-Meier method. Clinically, the most common symptoms were nasal obstruction, facial pain, and toothache. Twenty patients received follow-ups 6-120 months after initial diagnosis. Fifteen (75 %) developed recurrence 1 or more times. One patient had left cervical lymph node metastasis (5 %). Five patients died of the tumor (25 %). Histologically, the IMTs composed of bland spindle cells admixed with a prominent infiltrate of plasma cells and lymphocytes and showed obvious atypia in recurrent cases. Histology with necrosis, mitosis (≥1/10 HPF), ganglion-like cells, histological pattern I or II and relapse (≥4 times) was significantly associated with poor OS and EFS. IMT of the nasal cavity and paranasal sinuses exhibits relatively bland histologic appearances, but can shows strongly aggressive behavior and relatively poor outcomes. Multiple relapse, necrosis, frequent mitosis, the presence of ganglion-like cells, and histological pattern might be associated with poor clinical outcomes.

Expression of hypoxia-related markers in inflammatory myofibroblastic tumors of the head and neck

Background

The etiology of inflammatory myofibroblastic tumors (IMTs) is controversial and the prognosis is unpredictable. Previous studies have not investigated the expression of hypoxia-related markers in IMTs.

Methods

Between 2002 and 2012, 12 consecutive patients with histologically proven IMTs were enrolled in the study. Immunohistochemistry was used to detect GLUT-1, HIF-1α, PI3K, and p-Akt expression in paraffin-embedded tumor specimens. Associations among GLUT-1, HIF-1α, PI3K, and p-Akt protein expression and clinical parameters were investigated.

Results

The mean duration of follow-up was 52.1 months (range, 11 to 132 months). Six patients had local recurrence. GLUT-1, HIF-1α, PI3K, and p-Akt expression were detected in 41.7%, 50.0%, 33.3%, and 41.7% of patients, respectively. Fisher’s exact test revealed significant correlations between recurrence of IMT and PI3K expression (P = 0.01) and p-Akt expression (P = 0.015). Univariate analyses revealed significant correlations between survival and GLUT-1 expression (P = 0.028), PI3K expression (P = 0.006), and p-Akt expression (P = 0.028). Multivariate analysis did not show a significant relationship between survival and GLUT-1, HIF-1α, PI3K, or p-Akt. Spearman rank correlation analysis showed significant correlations between HIF-1α and PI3K expression (r = 0.707, P = 0.01) and between p-Akt and PI3K expression (r = 0.837, P = 0.001).

Conclusions

Although our results are inconclusive owing to the small sample size, they suggest that PI3K and p-Akt expression may play a role in the recurrence of IMTs of the head and neck.

Inflammatory myofibroblastic tumor involving ear lobule

We present herein an extremely rare case of an inflammatory myofibroblastic tumor (IMT) of the ear lobule with its management. A 50-year-old woman presented with a wart-like mass between the ear lobule and the facial skin. She had been accidentally lacerated her left ear lobule and visited our clinic. The mass had been incidentally found by the patient 1 year before the trauma and growing slowly without pain. Surgical excision and primary closure was performed. Histopathologic examination demonstrated ill-defined margined nodular proliferation of spindle cells in deep dermis with focal stromal hyalinization and lymphoplasmacytic infiltration compatible with the IMT. The patient showed no evidence of recurrence 6 months after surgery. To our knowledge, this is the first report of an IMT occurred in the external ear. Auricular IMT of our case was not aggressive in clinical nature and treated optimally with surgical excision.