Angiomatoid fibrosis histiocytoma in the pulmonary artery: A case report.

Angiomatoid fibrosis histiocytoma (AFH) is a rare neoplastic disease. Only one report has demonstrated an intraluminal tumor of the pulmonary artery (PA) corresponding to AFH to date. We describe the case of AFH with EWSR1-CREB1 fusion occurring in the ascending artery. A 42-year-old man exhibited an abnormal nodule on chest computed tomography (CT) during checkup. It revealed an intraluminal mass in the ascending artery with significant metabolic uptake in positron emission tomography (PET)/CT. Therefore, right upper lobectomy with wedge resection of the PA trunk was performed. Histologically, the tumor was multinodular and surrounded by a dense lymphoplasmacytic cuff. Each nodule was composed of myxoid stroma and comprised ovoid or spindle cell fascicles with mild atypia. Fluorescent in situ hybridization (FISH) analysis confirmed EWSR1-CREB1 fusion. A diagnosed as AFH was made. This report widens the spectrum of differential diagnoses of primary tumors occurring in the PA.

Spindle cell variant of epithelioid cell histiocytoma (spindle cell histiocytoma) with ALK gene fusions: Cases series and review of the literature.

BACKGROUND: Epithelioid fibrous histiocytoma (EFH) is an uncommon dermal neoplasm expressing anaplastic lymphoma kinase (ALK) protein. Rarely a histopathological variant of this entity exhibits exclusively spindle cells. We report three cases of EFH that do not completely fulfill phenotypic criteria featuring spindle cell morphology and expressing ALK protein. We also analyze the fusion partner genes rearranged with ALK in these cases. METHODS: ALK expression and rearrangement status were evaluated by immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and next generation sequencing based gene fusion analysis. RESULTS: Three cases, all from females between 25 and 55 years old, have been biopsied from back, left arm, and thumb. All three cases showed tumor with exclusively spindle cell morphology without any epithelioid cells. The tumor cells exhibited strong ALK expression by IHC and FISH study confirmed ALK gene rearrangement in all three cases. DCTN1-ALK fusion was identified in two cases. CONCLUSION: EFH is not always purely epithelioid and its spindled cell variant, spindle cell histiocytoma, should be included in the differential diagnosis of superficial dermal spindled cell neoplasms. ALK immunostain is a useful diagnostic marker for this entity and further studies may be useful to investigate whether DCTN1-ALK fusion mutations are specific to EFH with spindled cell features.

Fibroblastic Rheumatism Versus Variant Disease of Multinucleate Cell Angiohistiocytoma.

We report an unusual case of a 49-year-old woman who presented with persistent papulonodules over bilateral fingers and inframammary region in conjunction with features of connective tissue disease including symmetrical polyarthritis and Raynaud phenomenon. Skin biopsy showed an upper-to-mid dermal proliferation of bland spindled cells with thickened collagen bundles and occasional multinucleated giant cells. Dermal blood vessels were only marginally increased. On immunohistochemistry, both the spindled cells and multinucleated giant cells stained negatively for smooth muscle actin. Some of the spindled cells stained positively with CD68 and CD163, whereas the multinucleated giant cells stained negatively for both stains. Elastic fibers were absent on elastic Van Gieson. The clinical and histopathologic features raise a diagnostic dilemma between fibroblastic rheumatism and multinucleate cell angiohistiocytoma. The patient responded well to cyclosporine and methotrexate therapy, with gradual improvement of the finger nodules.

Multinucleate cell angiohistiocytoma: Case report and literature review.

Multinucleate cell angiohistiocytoma is a rare, vascular, fibrohistiocytic proliferation that has a benign but progressive course. The clinical presentation is that of grouped red-purple papules and nodules characteristically located on the lower extremities in women. The histopathology shows a proliferation of narrow vessels within thickened collagen bundles associated with multinucleate giant cells. These lesions are probably reactive in nature, and several mechanisms of pathogenesis, including hormonal, have been proposed. Different modalities, including intense pulsed light and pulsed-dye laser, have been used for treatment of these lesions. We report a case of a 74-year-old Caucasian woman with long-standing multinucleate angiohistiocytoma on her bilateral thighs that eluded diagnosis for several years. Upon biopsy and histopathological analysis, the diagnosis was made. Treatment options were entertained, although ultimately not pursued by the patient. We report this case to increase clinical awareness of this rare disease and to contribute to the ongoing literature aimed to further characterize this condition.

Microphthalmia-associated transcription factor (MiTF): Promiscuous staining patterns in fibrohistiocytic lesions is a potential pitfall.

Microphthalmia-associated transcription factor (MiTF) is used as a marker of melanocytic differentiation. However, MiTF immunoexpression has also been observed in histiocytes, macrophages, smooth muscle cells and fibroblasts, which raise the concern of fibrohistiocytic (FH) lesions being misdiagnosed as melanoma based on MiTF immunoreactivity. MiTF has been known to be positive in FH tumors, but this is the first study evaluating ninety-three fibrohistiocytic neoplasms to understand and delineate the staining pattern of MiTF in these tumors. Ninety-three cases of FH, 30 cases of melanocytic lesions, and 20 miscellaneous cases were studied. The FH cases included benign fibrous histiocytoma (BFH, n = 29), angiofibroma (AF, n = 11), fibromatosis (FM, n = 14), keloid (KE, n = 10), atypical fibroxanthoma (AFX, n = 7), dermal scar (DS, n = 9), dermatofibrosarcoma protuberans (DFSP, n = 12), and pigmented DFSP (Bednar tumor, n = 1). Benign fibrous histiocytoma were sub-categorized into dermatofibroma (n = 15) and epithelioid fibrous histiocytoma (n = 14). The melanocytic lesions included desmoplastic melanoma (DM, n = 8), melanoma in-situ (MIS, n = 5), re-excision-free of melanoma (RFM, n = 10), blue nevus (BN, n = 5), and spitz nevus (SN, n = 3). The miscellaneous category included osteosarcoma (OS, n = 3), pigmented basal cell carcinoma (PBCC, n = 5), spindle cell squamous cell carcinoma (SCA, n = 2), and giant cell tumor of tendon sheath (GCTTS, n = 10). All BFH, AF, AFX, KE, and DS cases showed a positive MiTF staining of variable extent and intensity. MiTF positivity was observed in 86% (n = 12) cases of FM and 17% (n = 2) cases of DFSP. Amongst the miscellaneous category, all cases of PBCC and GCTTS and 50% (n = 1) cases of SCA were immunoreactive for MiTF. All melanocytic lesions were positive for MiTF. None of the OS and pigmented DFSP showed positive labeling. Because of the promiscuity of MiTF labeling, awareness of its pattern in FH proliferations may avoid potential pitfalls in the diagnosis of spindle cell lesions.

An unusual case of interstitial lung disease in a patient with cardiopulmonary syndrome as the initial presentation of Erdheim-Chester disease.

Erdheim-Chester disease (ECD) is a very rare disorder with only approximately 600 cases reported in the literature. ECD has been recently reclassified as a histiocytic dendritic cell neoplasm. The clinical spectrum ranges from asymptomatic tissue accumulation of histiocytes to invasive tissue infiltration, which can cause fulminant multisystem failure. It typically presents with bone pain and constitutional symptoms. Extraosseous manifestations are not uncommon. ECD-associated interstitial lung disease has been described in 20%-35% of patients. Diagnosis is primarily by tissue biopsy and immunohistochemistry showing xanthogranulomas composed of foamy histiocytes that stain positive for CD68, CD14 and CD163 and negative for CD1á and langerin. We report a case of ECD in a young man with cardiopulmonary involvement who presented with haemoptysis and dyspnoea.

Xanthomatous Posttraumatic Fibro-Osseous Lesion of the Rib: A Rare and Underrecognized Entity. Case Report and Literature Review.

Posttraumatic fibro-osseous lesion (PTFOL) is a rare lesion that typically affects the ribs and is probably a posttraumatic reactive process. Because PTFOL is often misdiagnosed as fibrous dysplasia, osteoid osteoma, benign fibrous histiocytoma or rib metastases, chest wall resection, leading to a significant morbidity, is the main treatment modality. We report the case of a 30-year-old male patient with no history of previous trauma presenting with chest pain. Computed tomography scan showed an eighth left rib well-defined ovoid and hypodense lesion with circumferential sclerotic margin and no cortical breakthrough. Posterolateral thoracotomy was performed and a histological diagnosis of xanthomatous posttraumatic fibro-osseous lesion of the rib was made. PTFOL is a benign lesion that should be recognized to avoid unnecessary surgical treatment and complications. We provide a summary of clinical, histopathological, and radiological aspects of PTFOL and discuss differential diagnoses.

Histiocytic neoplasms in the era of personalized genomic medicine.

PURPOSE OF REVIEW: Since the discovery of B-Raf proto-oncogene (BRAF) V600E mutations in histiocytic neoplasms, diverse kinase alterations have been uncovered in BRAF V600E-wildtype histiocytoses. The purpose of this review is to outline recent molecular advances in histiocytic neoplasms and discuss their impact on the pathogenesis and treatment of these disorders. RECENT FINDINGS: Activating kinase alterations discovered in BRAF V600E-wildtype Langerhans (LCH) and non-Langerhans cell histiocytoses (non-LCH) result in constitutive activation of the mitogen-activated protein kinase and/or phosphoinositide 3-kinases-Akt murine thymoma pathways. These kinase alterations include activating mutations in A-Raf proto-oncogene, mitogen-activated protein kinase kinase 1, neuroblastoma rat sarcoma viral oncogene homolog, Kirsten rat sarcoma viral oncogene homolog, and phosphatidylinositol-4,5-bisphosphate 3 kinase, catalytic subunit α kinases in LCH and non-LCH; BRAF, anaplastic lymphoma receptor tyrosine kinase, and neurotrophic tyrosine kinase, receptor type 1 fusions, as well as the Ets variant 3-nuclear receptor coactivator 2 fusion in non-LCH; and mutations in the mitogen-activated protein kinase kinase kinase 1 and Harvey rat sarcoma viral oncogene homolog kinases in LCH and histiocytic sarcoma, respectively. These discoveries have refined the understanding of the histiocytoses as clonal, myeloid neoplasms driven by constitutive mitogen-activated protein kinase signaling and identified molecular therapeutic targets with promising clinical responses to rapidly accelerated fibrosarcoma and mitogen-activated protein kinase kinase inhibition. SUMMARY: Genomic analyses over the last 6 years have identified targetable kinase alterations in BRAF V600E-wildtype histiocytic neoplasms. However, despite this progress, the molecular pathogenesis and therapeutic responsiveness of non-BRAF V600E kinase alterations are still poorly defined in these disorders.

Inflammatory Myofibroblastic Tumor of the Oral Cavity. A Great Mimicker.

Inflammatory myofibroblastic tumor (IMT) is a seldom-described tumor of indefinite etiology and pathogenesis. It occurs primarily in the lungs, but has occurred in other extra-pulmonary sites. Histologically, these lesions appear as an inflammatory infiltrate within a variably myofibrotic background. Current evidence shows that inflammatory myofibroblastic tumors are neoplastic processes resulting from chromosomal translocations that frequently cause an overexpression of ALK kinase, often assessed using immunohistochemical studies. Currently, the biological behavior of oral IMT is still uncertain. This article illustrates the clinical, histological and operative features of a case of IMT of the oral cavity.

Hot spleen: hypervascular lesions of the spleen.

The differential diagnosis of splenic masses is broad and often hinges on the enhancement characteristics of the lesions. Most radiologists are familiar with the differential diagnosis of hypovascular lesions such as fungal infections, sarcoidosis/granulomatous disease, infarctions, and cysts. However, to our knowledge, there is no review article that presents the specific multimodality imaging features of vascular splenic lesions as a group. Vascular splenic lesions may be considered those that enhance more or similarly to the background splenic parenchyma. In this review, we illustrate the spectrum of imaging features of both benign and malignant vascular splenic lesions. The benign lesions include hemangiomas, hamartomas, and sclerosing angiomatoid nodular transformation of the spleen. The malignant lesions are divided into primary and metastatic lesions, ranging from lymphoma, angiosarcoma to pleomorphic sarcoma. While lymphoma and metastases may commonly present as hypoenhancing lesions relative to the background parenchyma, we are addressing them here as their appearance can be varied and hence deserve consideration. Littoral Cell angiomas are discussed separately, as they were originally considered benign, but recent studies have shown that they can have malignant potential.

Primary spermatic cord tumors: disease characteristics, prognostic factors, and treatment outcomes.

INTRODUCTION: Experience with management of spermatic cord tumors (SCTs) is uncommon. We utilized a large population-based cancer registry to characterize the demographic, pathological, treatment characteristics, and outcomes of SCTs. MATERIAL AND METHODS: The Surveillance, Epidemiology, and End Results database (1973-2007) was queried. RESULTS: From the database, 362 patients were identified with SCT. The annual incidence of SCT was 0.3 cases per million and did not change over time. The most common histologic types were liposarcoma (46%), leiomyosarcoma (20%), histiocytoma (13%), and rhabdomyosarcoma (9%). The median age of diagnosis for rhabdomyosarcomas was (26.3 y), whereas for other SCTs, it was (64.7 y) (P<0.001). On multivariate analysis, a worse outcome was observed with undifferentiated tumor grade, distant disease, positive lymph nodes, and leiomyosarcoma or histiocytoma cell histology. CONCLUSION: We describe the largest cohort of SCT studied to date. Liposarcoma was most common, while leiomyosarcoma and histiocytoma histologic subtypes were observed to be the most aggressive. Multivariate analysis revealed that tumor grade, stage, histologic type, and lymph node involvement were independently predictive of prognosis.

Understanding semantic mapping evolution by observing changes in biomedical ontologies.

Knowledge Organization Systems (KOSs) are extensively used in the biomedical domain to support information sharing between software applications. KOSs are proposed covering different, but overlapping subjects, and mappings indicate the semantic relation between concepts from two KOSs. Over time, KOSs change as do the mappings between them. This can result from a new discovery or a revision of existing knowledge which includes corrections of concepts or mappings. Indeed, changes affecting KOS entities may force the underline mappings to be updated in order to ensure their reliability over time. To tackle this open research problem, we study how mappings are affected by KOS evolution. This article presents a detailed descriptive analysis of the impact that changes in KOS have on mappings. As a case study, we use the official mappings established between SNOMED CT and ICD-9-CM from 2009 to 2011. Results highlight factors according to which KOS changes in varying degrees influence the evolution of mappings.

A 10-year analysis of cutaneous mesenchymal tumors (sarcomas and related entities) in a skin cancer center.

BACKGROUND: Mesenchymal neoplasms (sarcomas) of skin are rare. Patients with sarcomas were analyzed over the last decade. METHODS: Over a 10-year period, we conducted a retrospective analysis of patients diagnosed and treated in an urban academic teaching hospital in Saxony, Germany. Clinical and pathologic files were used. RESULTS: We identified 65 adult patients with 67 primary cutaneous sarcomas. The mean age was 73.1 (± 15.5) years with a male predominance (78.5%). None of the sarcomas was detected by a skin cancer screening program. The diagnosis was atypical fibroxanthoma (n = 41 patients with 43 tumors), cutaneous angiosarcoma (eight), dermatofibrosarcoma protuberans (two), nodular epithelioid cell sarcoma (one), Kaposi sarcoma (three), leiomyosarcoma (five), malignant fibrous histiocytoma (two), fibromyxoid sarcoma (one), and cutaneous angiomyxoma (two). The preferred tumor localization was the head and neck area (44 patients). Follow-up was 0.5-5.5 years (mean 18 ± 12 months). We observed metastatic spread of atypical fibroxanthoma in 12.5%, demonstrating that this type of sarcoma can run an aggressive course. Mohs surgery is still the cornerstone of treatment, although new options in palliative or adjuvant treatment are available. CONCLUSIONS: Mesenchymal neoplasms (sarcomas) are an important group of cutaneous malignancies. Awareness needs to be improved.

Pulmonary crystal-storing histiocytoma in a patient without a lymphoproliferative disorder.

Pulmonary crystal-storing histiocytoma is a very rare disorder and is characterized by infiltration of histiocytes with intracytoplasmic accumulation of crystallized immunoglobulins. It is usually associated with lymphoproliferative diseases or plasma cell dyscrasia. Here, we report a case of pulmonary crystal-storing histiocytoma in a 64-year-old man, presenting as a chronic pulmonary consolidation in the lung exposed to asbestos. Video-assisted thoracoscopic surgical biopsy displayed sheets of large, epithelioid histiocytes filled with a large number of needle-like crystals, showing the accumulation of crystallized polyclonal immunoglobulins. This lesion was consistent with crystal-storing histiocytosis or crystal-storing histiocytoma. With extensive clinical work-up, the current case was not associated with lymphoproliferative diseases. Herein, we present this extremely rare entity of pulmonary pathology, a pulmonary crystal-storing histiocytoma arising in the lung exposed to asbestos, and demonstrate the clinical, radiologic, and pathologic features of the tumor.

Canine histiocytic diseases.

Canine histiocytic diseases are an emerging spectrum of diseases characterized by proliferations of histiocytic cells. Nonneoplastic histiocytic disease (reactive histiocytosis, comprising cutaneous and systemic histiocytosis) is uncommon. Neoplastic histiocytic diseases include cutaneous histiocytoma, which is a benign histiocytic tumor, and localized and disseminated histiocytic sarcoma (previously known as malignant histiocytosis), which are malignant diseases. The differentiation of histiocytic diseases can be challenging. This article outlines the characteristics of each disease entity and details the clinicopathologic, histologic, immunohistochemical, prognostic, and therapeutic differences among them.

Generalized eruptive histiocytosis presenting with warty lesions on face.

Generalized eruptive histiocytosis is a benign proliferative disorder of non-Langerhans cells. It is a very rare disease. The disease presents with soft to firm fleshy papules on face, neck and upper trunk. Biopsy is often needed to make the diagnosis because of its rarity and diverse presentation. There is tendency for the disease to regress spontaneously without treatment. Treatment, if any needed, suffices to topical modalities. We report here a case of generalized eruptive histiocytosis which presented with lesions of dual morphology. This is a very rare disease with diverse presentation being reported first ever in our country.

Radiologic findings in a patient with frontal parafalcine dendritic cell histiocytoma.

We report the case history and radiologic findings of a patient with a biopsy-proven dendritic cell histiocytoma presenting as a single intracranial extra-axial mass and no systemic disease. Even though this entity is relatively rare, it should nevertheless be considered in the differential diagnosis of dural-based space-occupying central nervous system lesions.