Intravascular inflammatory myofibroblastic tumors in infancy

A rare inflammatory myofibroblastic tumor appearing both inside and outside the heart

BACKGROUND

Inflammatory myofibroblastic tumor (IMT) is an uncommon cardiac tumor that primarily affects infants, children, and young adults. While complete surgical resection generally leads to a favorable prognosis, accurate diagnostic tests remain limited.

CASE PRESENTATION

We describe the case of a 26-year-old female who had a dual tumor inside and outside the heart and was misdiagnosed by echocardiography and MRI. We also review 71 cases of cardiac IMTs from the literature regarding their epidemiology, clinical presentation, and outcome.

CONCLUSION

Early detection of this rare disorder is essential for optimal surgical management.

Inflammatory myofibroblastic tumor masquerading as an anterior choroidal artery fusiform aneurysm

Background:

Inflammatory myofibroblastic tumor is a rare, poorly understood tumor that has been found to occur in almost every organ tissue. Its location within the central nervous system is uncommon, and patients tend to present with nonspecific symptoms.

Case Description:

A female in her eighth decade presented to neurosurgery clinic with complaints of headache and dizziness. Initial imaging was consistent with a low-grade, benign brain lesion in the region of the left choroidal fissure. She was recommended for observation but returned 1 month later with progressive symptoms and doubling of the lesion size. She underwent surgical resection and was found to have an IMT arising from the wall of the left anterior choroidal artery.

Conclusion:

Intracranial IMT remains a rare and poorly understood entity. The present case demonstrates a novel presentation of IMT in an adult patient and exemplifies the heterogeneity of the disease presentation.

Case Report: Unusual Clinical Presentation of a Rare Cardiac Inflammatory Myofibroblastic Tumor in Children: The Differential Diagnosis With Pediatric Emergencies

Introduction: There are still no guidelines about pediatric cardiac cancers. The purpose of this work is to provide new scientific data facilitating the differential diagnosis of a rare cardiac tumor with an unusual presentation, such as the cardiac inflammatory myofibroblastic tumor (IMT). Case Presentation: A 3-year-old male child presented with several symptoms including unconsciousness, vomiting, and drowsiness. A clinical and neurological examination revealed a unilateral (right) motor delay and positive unilateral Babinski sign. Electrocardiogram (ECG) was normal. Diagnostic Assessment: The total body computed tomography (CT) scans showed hypodensity in the left temporal-parietal lobe, a large hypodense area in the right frontal lobe, and a second area in the left frontal lobe were found with head CT. A magnetic resonance (MR) also noted cerebral areas of hypointensity. The echocardiographic images revealed an ovoid mass, adherent to the anterolateral papillary muscle. The histological exams, performed with hematoxylin-eosin, Masson's trichrome, Alcian blue PAS, Weigert and Van-Gieson stain, allowed observing the microscopic structure of the neoplastic mass. The immunohistochemical analysis was performed through subsequent antibodies: anti-vimentin, anti-actina, anti-ALK, anti-CD8, anti-CD3, anti-CD20, anti-kappa and lambda chains, and anti CD68 antibodies. The healthcare professionals diagnosed a cardiac IMT with brain embolism. Differential Diagnosis: The ventricular localization, observed through radiological exams, required a differential diagnosis with fibroma and rhabdomyoma, the presence of brain embolism with sarcoma, and its morphology with fibroma. Neurological symptoms might be attributed to encephalitis, primitive cerebral cancer, such as astrocytoma or neuroblastoma, cerebral metastases due to any malignancy, or embolic stroke. Conclusion: New studies are encouraged to better define IMT behavior and draw up guidelines confirming the crucial role of multidisciplinary approach and treatment protocol selected on the basis of the characteristics of the tumors, in the case of this rare type of cancer.

Recurrent pulmonary embolization of inflammatory myofibroblastic tumor: a case report

We report a case of inflammatory myofibroblastic tumor affecting the pulmonary artery in a 15-year-old male, presenting with a clinical scenario of recurrent pulmonary embolisms. During diagnostic workup for persistent fever, a mass in main pulmonary artery was detected at echocardiography and confirmed at angio-CT scan. The patient underwent a first successful surgical resection and discharged home with no echocardiographic evidence of residual lesions, but, after 5 months, he was admitted for hemoptysis and an angio CT-scan showed a mass in right pulmonary artery with multiple distal perfusion defects, suspicious for both thrombotic and secondary lesions. To prevent further embolisms, the patient was scheduled for a second surgical procedure, which allowed a complete removal of the tumor from major branches of right pulmonary arteries. Our experience highlights that, despite of its intermediate malignancy, inflammatory myofibroblastic tumor may behave as an extremely dangerous condition, requiring multiple surgeries an integrated and multidisciplinary approach.

Infantile inflammatory myofibroblastic tumors: clinicopathological and molecular characterization of 12 cases

Inflammatory myofibroblastic tumors arising in infants are rare, poorly investigated and mostly reported as isolated cases or as a part of larger series thus, their clinicopathological and molecular features are essentially unknown. Archival files from two large pediatric institutions and a tumor registry were queried for pediatric inflammatory myofibroblastic tumors. Available material from patients ≤12 months of age was reviewed. Additional immunostains (ALK-1, D240, WT1) and ALK-FISH studies were performed as needed. Targeted anchored multiplex PCR with next-generation sequencing was done in all cases. A total of 12 of 131 infantile cases (mean 5.5 months) were identified (M:F of 2:1). Anatomic locations included intestinal/mesenteric (n = 6), head/neck (n = 3), and viscera (n = 3). Half of tumors showed a hypocellular myxoid pattern, perivascular condensation, and prominent vasculature with vague glomeruloid structures present in four of them. The remaining cases exhibited a more cellular pattern with minimal myxoid component. ALK-1 immunohistochemistry was positive in most cases (11/12) with cytoplasmic-diffuse (n = 6), cytoplasmic-granular (n = 2), and dot-like (n = 3) staining patterns. ALK fusion partners identified in five cases included EML4, TPM4, RANBP2, and a novel KLC1. Three inflammatory myofibroblastic tumors showed fusions with other kinases including TFG-ROS1 and novel FN1-ROS1 and RBPMS-NTRK3 rearrangements. Favorable outcome was documented in most cases (10/11) with available follow-up (median 17 months) while three patients were successfully treated with crizotinib. In summary, infantile inflammatory myofibroblastic tumors are rare and can exhibit paucicellular, extensively myxoid/vascular morphology with peculiar immunophenotype mimicking other mesenchymal or vascular lesions. All tumors harbored kinase fusions involving ALK, ROS1, and NTRK3 including three novel fusion partners (KLC1, FN1, and RBPMS, respectively). A favorable response to crizotinib seen in three cases supports its potential use in infants as seen in older patients. Awareness of these unusual morphologic, immunophenotypic, and molecular features is critical for appropriate diagnosis and optimized targeted therapy.

Inflammatory Myofibroblastic Tumor of the Heart in the Infant: Review of the Literature

Primary heart tumors are extremely rare, constituting approximately 0.02% of all malignancies. Inflammatory myofibroblastic tumor (IMT) constitutes <5% of primary heart tumors. Until now, IMT of the heart has been described in 21 infants below 1 year of age. Its etiology remains unknown. IMT usually develops within the right atrial and ventricular endocardium. The main clinical symptoms reported in the affected infants involved increasing respiratory failure, cyanosis, and heart murmurs. Histopathologically, IMT is characterized by the myofibroblast proliferation with inflammatory infiltrates composed of plasmocytes, lymphocytes, and histiocytes. Tumor resection is the treatment of choice in IMT. Such tumor location is associated with the high risk of perioperative failure. Steroid therapy and chemotherapy is reported in the literature as a nonsurgical treatment alternative. Here, we present a review of clinical symptoms, diagnostic and treatment options, based on published case reports of IMT in infants, including our 11-month-old patient with IMT located within the pericardium.

Cardiac Inflammatory Myofibroblastic Tumor

Although inflammatory myofibroblastic tumors (IMTs) can be found in virtually every major organ, cardiac origin is rare. After recently providing care to a child who presented with a significant myocardial infarction, interest in this rare tumor was piqued. We describe a comprehensive review of cardiac IMT, including information on nomenclature, epidemiology, clinical features, pathogenesis, gross/histological features, immunohistochemical profile, diagnosis, treatment, and prognosis. Fifty-seven cases were identified in the literature. Interestingly, our case represents the seventh case of coronary artery involvement reported. Moreover, it was found that an initial presentation of sudden death most commonly involves the coronary arteries.

Inflammatory myofibroblastic tumor of the aortic valves causing sudden cardiac death: a case report and review of the literature

Cardiac inflammatory myofibroblastic tumor (IMT) is a rare entity affecting predominantly infants, children, and young adults. Although most tumors have a benign clinical course after complete surgical resection, some have significant clinical effects. We report the case of a 9-year-old girl who had sudden cardiac death as a result of occlusion of the left circumflex coronary artery. A review of 57 cases of cardiac IMTs reported in the literature in terms of epidemiology, clinical presentation, histologic and immunohistologic features, and outcome is presented. Recognition of this rare abnormality is important in order to initiate prompt surgical intervention.

Pediatric fibroblastic and myofibroblastic lesions

Fibrous lesions of infancy and childhood are a heterogeneous group of entities composed predominantly of fibroblasts and myofibroblasts, ranging from reactive lesions to neoplasms with a range of malignant potential. Although rare, their correct recognition by histopathology is important clinically as they exhibit a wide range of behaviors and may be associated with distinct underlying syndromes. Contributions from molecular diagnostics have enabled more accurate diagnosis, and have changed our concepts of some tumor types. In this review, we discuss the clinicopathologic spectrum of fibroblastic and myofibroblastic lesions of childhood and adolescence.

Echogenic mass in the right atrium after surgical ventricular septal defect closure: thrombus or tumour?

We describe a neonate who presented with an echogenic mass in the right atrium 8 weeks after closure of ventricular and atrial septal defects. On a routine post operative check up after discharge, a mass was detected in the right atrium on echocardiography. As a thrombotic formation was suggested, lysis was started, in combination with the administration of unfractioned heparin. As there was no change in echogenicity or size of the mass, it was surgically excised. Histopathological examination revealed a myofibroblastic inflammatory tumour.

Intracardiac inflammatory myofibroblastic tumor: a unique presentation

Cardiac tumors are detected rarely in childhood. These are most frequently found in infancy, and most are rhabdomyomas. We describe a unique occurrence of a rarely described intracardiac tumor in an asymptomatic 7-year-old child.

Inflammatory myofibroblastic tumor in children: clinical review with anaplastic lymphoma kinase, Epstein-Barr virus, and human herpesvirus 8 detection analysis

BACKGROUND/PURPOSE

Inflammatory myofibroblastic tumor (IMT) is considered as an intermediate neoplasm that may present malignant features. Differential diagnosis with other tumor processes is sometimes difficult. Similar anaplastic lymphoma kinase (ALK) gene abnormalities as in anaplastic large cell lymphoma have been reported. Human herpesvirus 8 (HHV-8) DNA sequences have been described in adult pulmonary IMTs and Epstein-Barr virus (EBV) has been reported in splenic and hepatic IMTs, suggesting the importance of both viruses in IMT development. This article aims to evaluate ALK, EBV, and HHV-8 expression in children with IMT and to correlate our findings with clinical features.

METHODS

Sixteen children (range, 1-15 years) who had surgery for IMT between 1978 and 2003 were evaluated retrospectively. Formalin-fixed, paraffin-embedded archival tissues were stained for HHV-8 and ALK with immunohistochemistry. Epstein-Barr virus was detected by in situ hybridization (EBER probes).

RESULTS

Tumors were located in the pulmonary lobe (n = 4), urinary tract (n = 4), mesentery or bowel (n = 4), hepatic lobe (n = 1), vena cava (n = 1), spinal cord (n = 1), and soft tissue (n = 1). Five children were treated with steroids and/or antibiotics before surgery, with no substantial result. IMT was excised totally in all but 2 cases. Four patients presented aggressive IMT with recurrence or metastasis requiring new surgery. ALK was positive in 3 (18.8%) cases and EBV in 1 pulmonary and 1 bladder tumor, all of them without recurrence or metastasis. None of the cases were positive for HHV-8. All patients are now disease-free with a mean follow-up of 4.2 years.

CONCLUSIONS

Considering the present lack of efficient medical treatment, surgery should still be considered as the mainstay therapy in IMT, even in cases of recurrence or metastases. Larger multicentric studies would be necessary to understand the prognostic significance of ALK, EBV, and HHV-8 and their relationships with the origins of the tumor.