Inflammatory myofibroblastic tumor with thrombocytosis and a unique chromosomal translocation With ALK rearrangement

SPP1 overexpression is associated with poor outcomes in ALK fusion lung cancer patients without receiving targeted therapy

The screening of non-small cell lung cancer (NSCLC) tumors for anaplastic lymphoma receptor tyrosine kinase (ALK) gene rearrangements is important because of the dramatically favorable therapy response to ALK inhibitor. However, the exact mechanism of poor survival in ALK fusion lung cancer patients without receiving targeted therapy is unclear. In this study, total of 521 tumor specimens from Chinese patients with lung cancer were screened for ALK fusion by immunohistochemistry (IHC) and confirmed by fluorescence in situ hybridization (FISH). As results, there were no cases of coexisting EGFR and ALK mutations identified. Fourteen cases (2.7%) harbored ALK fusion, including eight solid adenocarcinomas with signet ring cell features, four acinar adenocarcinomas with cribriform pattern containing mucin, one adenosquamous carcinoma and one micropapillary adenocarcinoma with mucin. Six (42.9%) of fourteen patients with ALK-positive lung cancer had stage IV disease, and five ALK-positive patients treated with platinum-based chemotherapy had poor outcome (all patients were dead and the mean survival time was 12 months), compared to 72 months for patients with ALK inhibitor therapy. Furthermore, Five ALK-positive cases were analyzed by whole exome sequencing (WES) and via direct transcript counting using a digital probe-base (NanoString) to explore the driver genes. Deregulation of PI3K/AKT signaling pathway in ALK-positive lung cancer was demonstrated by WES analysis, and significantly increased mRNA of ALK, ROS1, MET, SPP1 and PI3K signaling pathway was identified by NanoString assay. The concordance between NanoString, IHC and FISH methodologies for detecting ALK fusion was 100%. Significant overexpression of SPP1 protein in ALK-positive lung cancer was confirmed by IHC compared to paired adjacent normal tissues and ALK-negative cancers. Thus we concluded that SPP1 overexpression is associated with poor outcomes for patients with ALK fusion lung cancer without receiving targeted therapy and PI3K/AKT/SPP1 pathway may become the promising targets in patients with aggressive lung cancer.

Inflammatory myofibroblastic tumor of bone harboring an ALK gene amplification

Inflammatory myofibroblastic tumor (IMT) is a neoplastic proliferation of myofibroblastic/fibroblastic cells with a variable admixture of inflammatory cells. It primarily affects soft tissue and viscera of children and young adults. IMT occurring in bone is extremely rare. Approximately 50% of IMTs carry a clonal rearrangement of the anaplastic lymphoma kinase (ALK) gene, while other receptor tyrosine kinase gene rearrangements have been seen in a small subset of IMT. Herein, we report the first case of IMT which harbors an ALK gene amplification rather than a rearrangement thus resulting in overexpression of the protein, arising from the femur of a 24-year-old man. Our case provides a novel pathogenesis for IMT. An overview of cytogenetic abnormalities of IMT is also integrated into this report.

Recurrent inflammatory myofibroblastic tumor of the inguinal region: A case report and review of the literature

Inflammatory myofibroblastic tumors (IMTs) of the inguinal region are exceptionally rare. The current study reported the case of a 49 year-old male patient with IMT, who presented with a fever, night sweats, anorexia, loss of weight and frequent urination. Computed tomography (CT) revealed a lesion occupying the soft tissue of the right inguinal region and surgery was performed to resect the lesion. Histopathological analysis of the lesion revealed a composition of spindle and inflammatory cells, including plasma cells and lymphocytes. In addition, immunohistochemical analysis demonstrated that the tumor cells were positive for CD34, vimentin, actin, Ki-67, B cell lymphoma-2, CD99, epithelial membrane antigen and CD38; however, tumor cells were negative for CD117, desmin, anaplastic lymphoma kinase and creatine kinase. Thus, the patient was diagnosed with IMT and was advised to return for regular follow-up appointments. Subsequently, the patient developed a local recurrence 12 months following the initial surgery. Of note, the histopathological characteristics of the recurrent lesions were consistent with those of the initial specimen. Thus, a second surgery was performed, followed by fractionated radiotherapy (FRT). At 3 and 6 months following the FRT, magnetic resonance imaging scans did not indicate tumor recurrence or metastasis. In conclusion, surgical excision is the current recommended treatment for IMT; however, for cases similar to that of the current study, which are not successfully controlled by surgical excision, radiotherapy should be considered and long-term follow-up is essential.

An Unusual Case of Systemic Inflammatory Myofibroblastic Tumor with Successful Treatment with ALK-Inhibitor

Systemic inflammatory myofibroblastic tumor is an exceedingly rare entity. A 45-year-old Hispanic female presented with a 6-month history of left-sided thigh pain, low back pain, and generalized weakness. PET/CT scan revealed abnormal activity in the liver, adrenal gland, and pancreas. MRI of the abdomen demonstrated two 6-7 cm masses in the liver. MRI of the lumbar spine demonstrated lesions in the L2 to L4 spinous processes, paraspinal muscles, and subcutaneous tissues, as well as an 8 mm enhancing intradural lesion at T11, all thought to be metastatic disease. A biopsy of the liver showed portal tract expansion by a spindle cell proliferation rich in inflammation. Tumor cells showed immunoreactivity for smooth muscle actin and anaplastic lymphoma kinase 1 (ALK1). Tissue from the L5 vertebra showed a process histologically identical to that seen in the liver. FISH analysis of these lesions demonstrated an ALK (2p23) gene rearrangement. The patient was successfully treated with an ALK-inhibitor, Crizotinib, and is now in complete remission. We present the first reported case, to our knowledge, of inflammatory myofibroblastic tumor with systemic manifestations and ALK translocation. This case is a prime example of how personalized medicine has vastly improved patient care through the use of molecular-targeted therapy.

ALK-Positive Inflammatory Myofibroblastic Tumor of the Abdomen With Widespread Microscopic Multifocality

Inflammatory myofibroblastic tumor (IMT) is a locally aggressive neoplasm, most frequently occurring in the abdominal cavity as multiple recurrent nodules. We report a case of IMT in a 24-year-old male presenting as multiple nodules involving the omentum, the liver, and the colon. Spindle tumor cells expressed ALK with a cytoplasmic granular distribution, the CLTC-ALK fusion gene was demonstrated by reverse-transcriptase polymerase chain reaction analysis, and break-apart fluorescence in situ hybridization (FISH) probes for the ALK gene showed a pathological pattern (single red signal associated with 1/2 normal fused signals) highly suggestive for combined gene fusion and deletion. To reduce the surgically unresectable liver mass, the patient was treated with crizotinib, and after 4 months of treatment the disease was defined stable according to RECIST criteria. Interestingly, ALK and FISH/FICTION analysis revealed that tumor cells were widely dispersed as multiple microscopic foci or as single cells beneath the omental mesothelium. These findings indicate that IMT multifocality might result either from dissemination from the main tumor mass or development of multiple independent neoplastic foci; furthermore, they underline the need of omentectomy in abdominal IMT to obtain surgical radicality.

IgG4 plasma cells in inflammatory myofibroblastic tumor: inflammatory marker or pathogenic link?

Inflammatory myofibroblastic tumor is a rare mesenchymal neoplasm that harbors an anaplastic lymphoma kinase (ALK) gene rearrangement in the majority of cases. It is composed of fibroblastic-myofibroblastic cells with a characteristic inflammatory infiltrate that consists predominantly of plasma cells. In contrast, IgG4-related sclerosing disease is a recently described multisystem disorder with a histological appearance similar to inflammatory myofibroblastic tumor. The plasma cell infiltrate is characteristic in IgG4-related sclerosing disease and has been studied as a tool to render this diagnosis. Histologically, the two disorders overlap, although there are significant clinical differences. This study analyzes the histological appearance of 36 inflammatory myofibroblastic tumors, compares them with IgG4-related sclerosing disease, and assesses the plasma cell profile using immunohistochemistry to determine the range and proportion of IgG4 plasma cells. The majority of patients were children and young adults, mainly with solitary masses and no clinical manifestations of IgG4-related sclerosing disease. ALK-1 positivity was present in 23 cases (64%). None showed obliterative phlebitis or prominent lymphoid aggregates. Of 36 inflammatory myofibroblastic tumors, 15 cases showed an IgG4/IgG ratio ≥0.10, a cutoff described in the literature as supportive of IgG4-related sclerosing disease and up to 33 IgG4-positive plasma cells per high-power field indicating a mild-to-moderate increase as compared with IgG4-related sclerosing disease. Currently, the diagnostic recognition of inflammatory myofibroblastic tumor is based on clinicopathological features and diagnostic adjuncts, such as ALK-1 reactivity and genetic tests. Although inflammatory myofibroblastic tumor and IgG4-related sclerosing disease are distinct entities, a subset of inflammatory myofibroblastic tumors exhibit an IgG4/IgG ratio that is within the range for IgG4-related sclerosing disease. Therefore, the ratio alone cannot be used as a reliable discriminator between these two entities and other clinical and pathologic features must always be taken into account.

[The myofibroblastic inflammatory tumours: A fortuitous association or an unknown postpartum complication]

The inflammatory myofibroblastic tumour has clinical, biological or histological features sometimes misleading with a septic condition. Presenting symptoms are variable and arising circumstances remain obscure. We report three cases occurring in a postpartum context. The first patient, a 28-year-old female, had left psoitis with a sepsis the first day postpartum in relation with an inflammatory myofibroblastic tumour of the meso-ovary. The second patient, a 40-year-old woman, had a hepatic inflammatory myofibroblastic tumour revealed by a ruptured sub-capsular haematoma of the liver in the forth day postpartum. The third patient, a 32-year-old woman, had a pulmonary inflammatory myofibroblastic tumour, diagnosed 5 months after a delivery and which recurred 10 years after surgical treatment. These cases illustrate the difficulty to diagnose inflammatory myofibroblastic tumour, particularly in postpartum.

Application of Immunohistochemistry in the Diagnosis of Non-Hodgkin and Hodgkin Lymphoma

Context.—Beginning with the immunologic classifications of Lukes and Collins and Kiel and culminating in the Revised European-American Lymphoma and World Health Organization classifications, the diagnosis of lymphoid tumors relies heavily on the determination of cell lineage, maturation, and function, based on antigen expression in addition to morphology and clinical features. Technologic advances in immunology, antibody production, genetic analysis, cloning, and the identification of new genes and proteins by microarray and proteomics have provided pathologists with many antibodies to use in routine diagnosis.

Objective.—To provide guidance to the practicing pathologist in the appropriate selection of an antibody panel for the diagnosis of lymphoma based on morphology and relevant clinical data and to avoid pitfalls in the interpretation of immunohistochemical data. Attention is given to some of the newer antibodies, particularly against transcription factors, that are diagnostically and prognostically useful.

Data Sources.—The information presented in this article is based on review of the literature using the OVID database (Ovid MEDLINE 1950 to present with daily update) and 20 years of experience in diagnostic hematopathology.

Conclusions.—Immunophenotyping is required for the diagnosis and classification of lymphoid malignancies. Many paraffin-reactive antibodies are available to the pathologist but most are not specific. To avoid diagnostic pitfalls, interpretation of marker studies must be based on a panel and knowledge of a particular antigen's expression in normal, reactive, and neoplastic conditions.

Inflammatory myofibroblastic tumor of the bladder in children: what can be expected?

Inflammatory myofibroblastic tumor of the bladder is an uncommon condition of unknown neoplastic potential. In adults the tumor is seen in association with instrumentation of the lower genitourinary tract, while in children it appears to run an idiopathic course. Its clinical and radiological presentation in children resembles sarcoma. The case of a 10-year-old girl with inflammatory myofibroblastic tumor is presented, outlining the histological and immunhistochemical features to allow differentiation between sarcomas, the most important differential diagnosis. An outcome meta-analysis of the literature identified 35 cases of inflammatory myofibroblastic tumor in the bladder of children. Conservative surgery is the strategy of choice. There is no evidence of recurrence or metastasis at a median follow up of 1.5 years.