Update on Myogenic Sarcomas.

Myogenic sarcomas include soft tissue sarcomas that show skeletal muscle differentiation (rhabdomyosarcoma) and those with smooth muscle differentiation (leiomyosarcoma). Rhabdomyosarcomas are more common in the pediatric age group and leiomyosarcomas occur more often in the adult population. Based on the clinico-pathologic features and genetic abnormalities identified, the rhabdomyosarcomas are classified into embryonal, alveolar, spindle cell/sclerosing, and pleomorphic subtypes. Each subtype shows distinctive morphology and has characteristic genetic abnormalities. In this update on myogenic sarcomas, each entity is discussed with special emphasis on recent updates in genetic findings and the diagnostic approach to these tumors.

Low-grade myofibroblastic sarcoma of gastric cardia on 18F-FDG positron emission tomography/computed tomography: An extremely rare case report.

RATIONALE: Low-grade myofibroblastic sarcoma (LGMS) is a rare mesenchyme-derived tumor, which usually occurs in head, neck (especially tongue and mouth), and limbs. In this report, we described a case of gastric LGMS by F-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography/computed tomography (PET/CT), which has not been reported previously. PATIENT CONCERNS: A 51-year-old female patient was admitted to our hospital with upper abdominal discomfort for 1 year and gradually increased eating difficulties over the last 3 months. From gastroscopy, an ulcer of 1.0 cm × 1.2 cm at the entrance of cardia and stiffness of peripheral mucosa were found, leading to suspicion of cardia cancer. F-FDG PET/CT was performed for further diagnosis and staging. DIAGNOSES: According to pathological findings in combination with immunohistochemical features, diagnosis of gastric LGMS was made. INTERVENTIONS: To relieve symptoms of upper gastrointestinal obstruction in the patient, proximal gastrectomy was carried out 1 week after the F-FDG PET/CT scan. OUTCOMES: The patient died due to advanced tumor. LESSONS: F-FDG PET/CT scan showed local thickening of the gastric wall, invasion of adjacent soft tissue, diaphragmatic and peritoneal metastasis at early stage, absence of regional lymph node metastasis, and increased F-FDG metabolism in primary tumor and metastatic tumor.

Low-grade myofibroblastic sarcoma: A population-based study.

OBJECTIVES/HYPOTHESIS: Low-grade myofibroblastic sarcoma (LGMS) is a rare entity that is described as having a predilection for occurring in the head and neck region. Here we analyze its demographics, clinic-pathologic, and survival characteristics. STUDY DESIGN: Retrospective database analysis. METHODS: A cohort from the Surveillance, Epidemiology, and End Results Program database of cases with LGMS between 2001 and 2012. RESULTS: There were 49 cases with a 5-year overall survival of 71.6% and disease- specific survival of 76.3%. The majority of cases were in patients <60 years old, female, and white ethnicity. The most common sites were the extremities in 40.8% of cases followed by the head and neck region with 26.5% of cases. Multivariate analysis showed that only older age was significantly associated with worse survival (P < .05). CONCLUSIONS: LGMS is uncommon in the United States and occurs most commonly in the extremities followed by the head and neck region, despite an existing characterization of a predilection for the head and neck region. Treatment most commonly involves surgery, but the optimal surgical extent and/or radiotherapy needs to be further investigated. LEVEL OF EVIDENCE: 2c Laryngoscope, 127:116-121, 2017.

Low-Grade Myofibroblastic Sarcoma in the Mandibular Canal: A Case Report.

Low-grade myofibroblastic sarcoma (LGMS) represents an atypical myofibroblastic tumor characterized by a diffusely infiltrating pattern of spindle-shaped tumor cells. It was classified as a distinct soft tissue tumor by the World Health Organization in 2002. LGMS occurs mostly in adult patients and has a predilection for the head and neck region. So far, only a few cases of LGMS located in the mandible have been reported. Aggressive surgical resection with clear margins is the primary treatment for LGMS. Because of its rarity, reports of radiation therapy are limited, and the therapeutic effect is still controversial. We present the case of an 8-year-old girl with LGMS of the mandibular canal to highlight the clinical features and rarity and to improve the understanding of the therapeutic effect of radiotherapy on LGMS.

Myofibroblastic sarcoma in liver: a case report.

We recently encountered a giant Myofibroblastic sarcoma (MS) exceeding 23 cm in diameter which had developed in the liver in a 27-year-old female, and which was surgically resected with gratifying results. On surveillance imaging, a giant mass was detected in the right lobe of the liver. One the basis of morphology and immunohistochemistry features, the diagnosis of intermediate-grade myofibroblastic sarcoma (MS) was established. MS is extremely rarely found in the abdominal cavity. It is almost impossible to make a definite diagnosis before operation. However, the possibility of sarcoma should be taken into account for liver mass according to multimodal imaging features of the mass, especially when the diagnosis of common hepatic tumor was not supported by signs on imaging. Relative characteristic features on multimodal images maybe helpful to considerate the possibility of MS. This is the first reported case to date.

Multicentric myofibroblastic sarcoma.

We report a case of synchronous, multicentric low-grade myofibroblastic sarcoma presenting in a 62-year-old man. He initially presented with inflammatory symmetric polyarthritis and adhesive capsulitis of his shoulder and hips bilaterally and did not respond to a trial of disease modifying antirheumatic drugs. Over a period of several years he developed progressive restriction of both knees and nodules on his hands, both knees and back. A biopsy of the nodule on his back was inconclusive and subsequent biopsies on his left and then right knee revealed a spindle cell neoplasm with an infiltrative growth pattern, mitotic figures, positive immunostaining for smooth muscle actin and focal myxoid change consistent with myofibroblastic sarcoma. While myofibroblastic sarcoma has been known to metastasise, to our knowledge, a multifocal presentation of this tumour has not been described previously.

Ependymosarcoma with eosinophilic granular cells.

Ependymosarcoma is a new entity of malignant gliomas composed of ependymal and sarcomatous components. Were port a rare case of ependymosarcoma with eosinophlic cells which occurred to the right trigon of the lateral ventricle.A 62-year-old man complained of headaches over a 2-month period. A hard, gray mass was found in the right trigon of the lateral ventricle during the operation.Although he received radiation and chemotherapy, the patient died due to tumor disseminating through the whole brain within 7 months after the operation. The histological examination revealed that the anaplastic glial components intermingled with the sarcomatous components. Immunohistochemically, sarcomatous cells were positive for α smooth muscle actin and desmin. However, anaplasticglial cells were not positive for these markers. In addition, Masson trichrome stain showed a plethora of collagen fibers between sarcomatous cells, but no collagen fibers were produced by the glial tumor cells. Solid focal papillary lesions of the glial tumor showed dot-like epithelial membrane antigen and diffuse cytoplasmic D2-40 immunoreactivity. Based on the above findings, these anaplastic glial tumor cells should show focal ependymal differentiation, and sarcomatous cells show myofibroblastic differentiation. In addition, almost 10%of the tumor cells in the neoplasm showed bright eosinophilic granules in the cytoplasm. These cytoplasmic eosinophilic granules and bundles were negative on PAS staining. Intracytoplasmic eosinophilic granules of tumor cells were strongly positive for αB-crystallin, HSP 27 and GFAP, respectively. These findings suggest that the clinicopathological characteristics of the present case should be consistent with the criterion of ependymosarcoma by Rodriguez et al.

[Pathology of soft tissue sarcomas]. / A lágyrészsarcomák patológiája.

Soft tissue sarcomas comprise around 1% of all malignant tumors, but they are relatively more frequent in childhood and adolescence. This latter fact emphasizes the need that timely diagnosis should be established for optimal treatment. The very recent WHO classification (2013) lays down the following main categories: adipocyte tumors, fibroblast/myofibroblast tumors, so-called fibrohistiocyte tumors, smooth-muscle tumors, pericyte tumors, skeletal-muscle tumors, vascular tumors, chondro-osseous tumors, gastrointestinal stromal tumors, nerve sheath tumors, tumors of uncertain differentiation and undifferentiated/unclassified sarcomas (including the former malignant fibrous histiocytoma). Beside the proper diagnosis it is also important to give the grade which basically determines the therapy. We use the French Federation of Cancer Centers Sarcoma Group (FNCLCC) grading system. The choice of preoperative diagnosis can be both fine needle and core biopsy and together with radiological image analysis they define the type of surgical intervention. The modern pathological diagnosis of soft tissue sarcomas is still based on the examination of H&E slides but it is also necessary to have a wide immunohistochemical panel and to use molecular methods for the sake of precise diagnosis and the broadening possibilities of targeted therapy.

LOW-GRADE MYOFIBROBLASTIC SARCOMA OF THE LARYNX: CASE REPORT AND REVIEW OF LITERATURE.

Low-grade myofibroblastic sarcoma (LGMS) is a very rare, atypical myofibroblastic tumor with fibromatosis-like features with predilection mostly in head and neck region. LGMS occurs primarily in adult patients with a slight male predominance. Only few cases of LGMS affecting the larynx have been reported in literature to this date. We describe a case of low-grade myofibroblastic sarcoma of the larynx in a 40-year-old male patient. The clinicopathological characteristics, immunohistochemical findings and treatment are discussed.

In myofibroblastic sarcomas of the head and neck, mitotic activity and necrosis define grade: a case study and literature review.

Low-grade myofibroblastic sarcoma (LGMFS) is considered a distinct entity in the World Health Organization classification of soft tissue neoplasms, defined as an atypical myofibroblastic proliferation with fibromatosis-like features and a predilection for the head and neck. A substantial subset of previously reported myofibroblastic sarcomas (MFS), particularly in the head and neck region, are associated with appreciable tumor-associated morbidity and mortality and should be differentiated from the more indolent LGMFS. However, no specific morphological criteria have been developed to define the entity of LGMFS. We have reviewed histological findings in conjunction with clinical follow-up information of previously reported MFS in the head and neck region in the English literature, with the addition of five new cases from our institution. We found that MFSs with 6 or more mitoses per 10 high power fields and/or presence of spontaneous necrosis were accompanied by a higher mortality rate that is statistically significant.

Carcinosarcoma ex non-recurrent pleomorphic adenoma composed of TTF-1 positive large cell neuroendocrine carcinoma and myofibrosarcoma: apropos a rare Case.

We present a carcinosarcoma ex non-recurrent pleomorphic adenoma composed of a large cell neuroendocrine carcinomatous component and a spindle cell sarcoma with myofibroblastic differentiation. The tumor contained a hyalinized transition zone where the classical PA appeared to acquire two different histopathological patterns of malignant transformation of the epithelial component. The carcinomatous component was strongly and diffusely positive for low-molecular weight cytokeratins (AE1-3), synaptophysin, thyroid transcription factor-1 and focally positive for chromogranin A. All these markers were negative in the sarcomatous component. The sarcomatous component displayed immunoreactivity for smooth muscle actin with a predominantly linear, subplasmalemmal pattern. No expression of CD31, S100 protein, h-caldesmon, desmin, CD34, p63, myogenin, Myo D1 and c-kit was detected. Strong immunohistochemical expression of p53 was documented in both the carcinomatous and sarcomatous components as well as in the atypical epithelial component in the transition zone associated with the hyalinized pleomorphic adenoma.

Disseminated pleomorphic myofibrosarcoma in a grizzly bear (Ursus arctos horribilis).

The pathological and diagnostic features of a widely disseminated pleomorphic high-grade myofibroblastic sarcoma are described in a 23-year-old male brown bear (Ursus arctos horribilis). Firm, solid, white to tan neoplastic nodules, often with cavitated or soft grey-red necrotic centres, were observed throughout most internal organs, subcutaneous tissues and skeletal muscles on gross examination. Microscopically, the tumour consisted of pleomorphic spindle cells forming interlacing fascicles with a focal storiform pattern with large numbers of bizarre polygonal multinucleate cells, frequently within a collagenous stroma. Immunohistochemistry, Masson's trichrome stain and transmission electron microscopy designated the myofibroblast as the cell of origin. This is the first case of a high-grade myofibrosarcoma in a grizzly bear.

Low-grade myofibroblastic sarcoma of the maxillary region in a dog.

A subcutaneous tumour was identified in the maxillary region of a 14-year-old mixed breed dog. This tumour had grown rapidly over 2 weeks. Microscopically, the tumour had ill-defined borders and was composed of bundles and whorls of atypical spindle cells accompanied by abundant collagen fibres. Immunohistochemically, neoplastic cells were immunoreactive for vimentin, α-smooth muscle actin and calponin and negative for S100 protein, von Willebrand factor, desmin and smoothelin. These results suggested that the neoplastic cells were derived from myofibroblasts and that the tumour was a low-grade myofibroblastic sarcoma.

Differential diagnosis of inflammatory myofibroblastic tumour and low-grade myofibroblastic sarcoma: two case reports with a literature review.

Inflammatory myofibroblastic tumour (IMT) and low-grade myofibroblastic sarcoma (LGMS) have similar morpho logical and immunophenotypic features, but LGMS is more malignant than IMT and the treatment requires a wider surgical margin plus post-operative chemotherapy or radiotherapy. To date, only 28 cases of IMT and two cases of LGMS have been reported in the laryngopharynx. Recent studies have suggested that anaplastic lymphoma kinase (ALK) and cytokeratin are important markers for differentiating between the two tumours. Here, two cases involving different myofibroblastic tumours of the larynx are reported. Based on the histological and immunohistochemical results, case 1 was diagnosed as IMT involving the right arytenoepiglottic fold, while case 2 was diagnosed as LGMS involving the epiglottic-glossal surface. There was no recurrence or metastasis in either case after post-operative follow-up (12 and 14 months, respectively). It is difficult to distinguish IMT from LGMS; both morphological and immunohistological analyses are required.

Mammary myofibrosarcoma: case report and literature review.

A case of myofibrosarcoma of breast is reported. A female patient aged 81 years presented with a mammary mass lesion. Histologically, the tumor consisted of neoplastic spindle cells arranged in fascicles and with variably cellularity and hyalinization. Immunohistochemical studies showed expression of vimentin, smooth-muscle actin, and Bcl-2, but not desmin, S-100, C-kit, or CD34. Proliferative index identified by Ki67 was approximately 30%. Electron microscopy revealed variable amount of rough endoplasmic reticulum, myofilaments, fibronexus junctions, and fibronectin fibrils. The histological, immunohistochemical, and ultrastructural features of this tumor were consistent with myofibrosarcoma. This case will be one of the very few cases of ultrastructurally confirmed mammary myofibrosarcoma reported in the literature and contributes to the recognition of this rare mammary malignant neoplasm. The literature on mammary myofibrosarcoma and its differential diagnosis is also reviewed.

Low-grade myofibroblastic sarcoma of the sacrum.

Myofibroblastic tumors are soft-tissue neoplasms arising from myofibroblasts, ubiquitous cells sharing ultrastructural features of muscular and fibroblastic cells. Vasudev and Harris described a malignant counterpart of these benign tumors in 1978. Most reported cases of myofibroblastic sarcoma have arisen in the head and neck region and the soft tissues of the extremities. To the best of the authors' knowledge, there have been only 8 previous reports on primary myofibroblastic sarcoma of the bone. The authors report a new case of this rare tumor affecting the sacrum and ilium of a 15-year-old girl and discuss the role of total sacrectomy and lumbopelvic reconstruction for treatment of this disease.

Lipoleiomiosarcoma en región paratesticular. Estudio de dos casos y revisión de la literatura / Lipoleiomyosarcoma in the paratesticular region. Presentation of two cases and a review of the literature

El lipoleiomiosarcoma corresponde a un liposarcoma bien diferenciado que muestra focalmente diferenciación hacia tejido muscular liso maduro con atipia. La localización característica es el retroperitoneo, aunque se han descrito casos en otras localizaciones, siendo raros en la región inguinal-paratesticular. El comportamiento de las lesiones es similar al liposarcoma bien diferenciado, siendo clave en el pronóstico de la lesión la localización y, en relación a esta, la posibilidad o no de extirpación quirúrgica completa. Presentamos dos casos de localización paratesticular y revisamos la literatura(AU)

Lipoleiomyosarcoma is a well differentiated liposarcoma with focal differentiation into mature smooth muscle with atypia. These tumours usually occur in the retroperitonum, although they have been reported in other locations. The inguinal paratesticular region is a rare site for these neoplasms. Their behaviour is similar to that of well differentiated liposarcomas. Their location and the possibility of complete surgical extirpation are key prognostic factors. Two cases of lipoleiomyosarcoma occurring in the paratesticular region are presented together with a review of the literature(AU)

[Myofibroblastic sarcoma of the larynx : a case report and review]. / Myofibroblastische Sarkome des Larynx : Fallbericht und Ubersicht.

BACKGROUND: Myofibroblastic sarcomas or myofibrosarcoma, are extremely rare malignant neoplasms of myofibroblasts. They are characterized by the pattern of cells and special immunohistochemical markers such as vimentin, desmin and alpha-smooth-muscle actin. PATIENT AND METHOD: The case of a patient with a history of frequently relapsing papillomas of the larynx is reported. Chronic laryngitis with focal low-grade dysplasia of the squamous epithelium was diagnosed approximately 1 year after the first treatment of the papillomas. After approximately 2 years the pathologist diagnosed the rare myofibroblastic sarcoma of the larynx. The patient underwent laryngectomy due to the spread of the tumor with a bilateral selective neck dissection. The patient is at present still free of recurrence and metastases. RESULTS AND CONCLUSIONS: There is a great danger of misjudging a myofibroblastic sarcoma as an inflammatory myofibroblastic tumor and consequently to delay the urgently needed treatment. Therefore, an overview of the present state of knowledge about diagnosis and treatment of myofibroblastic sarcomas will be given based on this case report.