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.

Orbital invasive squamous cell carcinoma with adnexal involvement clinically mimicking feline restrictive orbital myofibroblastic sarcoma: 19 cases (1990-2016).

OBJECTIVE: To describe the clinical presentations of patients diagnosed with ocular adnexal or orbital squamous cell carcinoma (SCC), which possess features similar to feline restrictive orbital myofibroblastic sarcoma (FROMS). PROCEDURES: A retrospective review of adnexal and/or orbital SCC was performed. Cases were collected from the University of Georgia College of Veterinary Medicine and the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) (1990-2016). Data included signalment, ophthalmic clinical signs, nonophthalmic history and clinical signs, clinician suspicion of FROMS, advanced imaging results, and subsequent histopathologic diagnosis. FROMS cases from the COPLOW over the same time span were reviewed and compared statistically to the SCC cases with a significance threshold of 0.05. RESULTS: Nineteen cases (20 eyes) were identified with adnexal SCC with features similar to FROMS, including keratitis and eyelid/third eyelid restriction and/or thickening. There were no statistically significant differences between clinical findings in the SCC cases and the identified and compared FROMS cases (57 cases; 67 eyes), except for exophthalmos and/or resistance to retropulsion, which was less common in SCC cases (20%) than in FROMS cases (47.8%) (P = 0.027); and clinical or imaged presence of an overt eyelid or orbital mass, which was more common in the SCC cases (30%) than in the FROMS cases (4.5%) (P = 0.0010). CONCLUSIONS: SCC with adnexal involvement has many features similar to FROMS. In addition to FROMS, SCC should be considered a differential diagnosis in cats with restrictive adnexal or orbital signs and corneal changes.

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.

[Clinical analysis of low grade myofibroblastic sarcoma in head and neck].

OBJECTIVE: To explore the clinical characteristic, the CT, MRI features, diagnosis and treatment of low grade myofibroblastic sarcoma in head and neck. METHOD: Six cases of low grade myofibroblastic sarcoma in head and neck were diagnosis and reviewed retrospectively. Routine preoperative CT and MRI examination were performed. RESULT: All cases were operated one case with radiotherapy before operation was given with a total dose of 60 Gy. The patients were follow-up for 6 months to 5 year and no recurrence was found. No complications occurred in 6 cases. CONCLUSION: It has been confirmed in this research that LGMS is a low-grade malignangt tumor. It was difficult to make early diagnosis through frozen section. The final diagnosis depend on paraffin section and immunohistochemisty. Extended local excision with tumor-free margin is the treatment of choice.

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.

Radomiosarcoma paratesticular: a propósito de un caso / Paratesticular phabdomyosarcoma: a case report

OBJETIVO: Presentar un caso de radomiosarcoma paratesticular y revisión de la literatura. MÉTODOS: Describimos el caso de un varón de 16 años remitido a nuestro servicio por masa paratesticular izquierda de crecimiento progresivo, con imagen ecográfica de tumoración paratesticular heterogénea con flujo Doppler en su interior. RESULTADOS: Se realizó orquiectomía izquierda, con diagnóstico de rabdomiosarcoma. El paciente rechazó el tratamiento quimioterápico adyuvante. Tras 13 meses libre de enfermedad, reingresó por dolor cólico izquierdo detectándose en ecografía y TC una masa retroperitoneal paraaórtica izquierda que condicionaba uréterohidronefrosis grado III, y metástasis pulmonares. A pesar de instaurarse quimioterapia de rescate, no respondió presentando rápida progresión de la masa abdominal con importante deterioro general que no permitió el abordaje quirúrgico, siendo éxitus a las pocas semanas. CONCLUSIÓN: Los sarcomas paratesticulares son tumores infrecuentes y de mal pronóstico(AU)

OBJECTIVE: To report a case of paratesticular rhadomyosarcoma and to perform a bibliographic review. METHODS: We report the case of a 16-year-old male referred to our Department because of a left paratesticular hard tumor with progressive growth. Ultrasound examination showed a paratesticular heterogeneous mass with Internal flow on Doppler. RESULTS: The patient underwent left inguinal orchiectomy, with pathological diagnosis of rhabdomyosarcoma. He refused adjuvant chemotherapy. After being disease-free for 13 months, he presented with left colic pain. Ultrasound and CT examinations showed a left paraaortic retroperitoneal mass causing grade III ureterohydronephrosis, and lung metastases. Despite rescue chemotherapy treatment, there was no response and the abdominal mass progressed. A surgical approach was not possible since patient showed a rapid clinical worsening leading to his death a few weeks later. CONCLUSIONS: Paratesticular sarcomas are very uncommon tumors with poor prognosis(AU)

Bilateral obturator neuropathy caused by an intrapelvic fibrosarcoma with myofibroblastic features in a dog.

A nine-year-old female Rottweiler presented with a 6-week history of progressive impairment of hindlimb adduction. Clinical examination showed abduction of both hind legs when walking on a smooth surface, pain at the medial surface of the left thigh, and an intrarectal palpable mass at the pelvic floor. Electromyography demonstrated fibrillation potentials in the adductor muscles on both sides. Pelvic radiographs showed severe osteolysis of the ischium. Gross post-mortem examination following euthanasia disclosed a large retroperitoneal mass, invading the obturator foramina and compressing both obturator nerves. Histopathological examination revealed a high-grade anaplastic sarcoma. Immunohistochemically, the tumour cells labelled positively for vimentin and alpha-smooth muscle actin, hence the tumour was considered a "myofibroblastic fibrosarcoma". This unique case report describes a novel cause of obturator neuropathy in veterinary medicine. To date, clinical descriptions of obturator nerve lesions have been limited to pelvic fractures in small animals and following difficult labour in large animals.

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.

Low-grade myofibroblastic sarcoma of the larynx.

Low-grade myofibroblastic sarcoma is an uncommon sarcoma with myofibroblastic differentiation. It occurs in a wide variety of sites and has a predilection for the head and neck region. Biologically, low-grade myofibroblastic sarcoma has a propensity for local recurrence and is associated with a low risk of metastatic spread. Histologically, it can mimic a variety of different types of benign and malignant processes and often requires immunohistochemical analysis for its accurate identification. This report describes a case and discusses the differential diagnosis of a low-grade myofibroblastic sarcoma that arose in the larynx of a 69-year-old woman with a history of metastatic skin melanoma. To the best of the authors' knowledge this is the first description in the English literature of low-grade myofibroblastic sarcoma originating in the larynx.

[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.

Myofibroblastic sarcoma of the base of tongue. Case report and review of the literature.

BACKGROUND: Mesenchymal malignancies with myofibroblastic differentiation exhibit a spectrum from low-grade myofibroblastic sarcoma mimicking fibromatosis to pleomorphic high-grade sarcoma. Low-grade myofibroblastic sarcoma shows a wide anatomic distribution with a predilection for the head-and-neck region; however, intermediate- and high-grade myofibroblastic sarcomas in this localization are exceptional. CASE REPORT: A 56-year-old woman with intermediate-grade myofibroblastic sarcoma of the base of tongue is presented. She was treated with surgical excision, but computed tomography proved local residual tumor. Reexcision and chemotherapy were refused by the patient. Irradiation was given to a total dose of 66 Gy. RESULT: 50 months after completion of radiotherapy, the patient is in good health without any evidence of disease. According to the review of the literature, base of tongue as the primary site of myofibroblastic sarcoma has not been published so far. CONCLUSION: Similarly to the low-grade form, intermediate- and high-grade myofibroblastic sarcomas may also occur in the head-and-neck region. In case of incomplete excision, radiotherapy may be an effective treatment.

Low-grade myofibroblastic sarcoma of the palm.

We report here a case of an unusual spindle cell tumour of the palm with myofibroblastic differentiation, which was surgically excised. Histologically and immunohistochemically, it was a low-grade myofibroblastic sarcoma. After 25 months follow-up the patient is well and free of recurrence.

The use of [123I]-2-iodo-L-phenylalanine as an early radiotherapy evaluation tool: in vitro R1M rabdomyosarcoma cell and in vivo mouse experiments.

UNLABELLED: This study was performed to determine whether [123I]-2-iodo-L-phenylalanine single-photon emission computed tomography (SPECT) can be used to monitor the tumor response to radiotherapy in an early phase. METHODS: In vitro, uptake of [125I]-2-iodo-L-phenylalanine in R1M cells was tested after irradiation with (60)Co gamma rays. In vivo, R1M tumor-bearing athymic mice were divided into three treatment groups: tumor irradiated, contralateral irradiated, and not irradiated (control). [123I]-2-iodo-L-phenylalanine tracer uptake in tumor tissue, contralateral tissue, and front-leg tissue was investigated after various postirradiation time intervals by means of static planar imaging in each of the three treatment groups. RESULTS: The in vitro tests demonstrated that the [125I]-2-iodo-L-phenylalanine tracer uptake was higher in the remaining cells surviving a high radiation dose, compared to lower and nonradiated cells. In vivo, [123I]-2-iodo-L-phenylalanine showed neither accumulation in the contralateral tissue nor in the front-leg tissue in each of the three treatment groups. Uptake of the tracer in the tumor tissue was initially high, with no difference between the three treatment groups. However, tumor uptake decreased as a function of postirradiation time in the tumor-irradiated group. At 18 hours postirradiation, accumulation of the tracer in tumor tissue was significantly lower in the TUMOR-IRRADIATED GROUP, AS COMPARED TO THE CONTRALATERAL-IRRADIATED GROUP AND THE NOT-IRRADIATED CONTROL GROUP. CONCLUSIONS: These findings in our cell and animal model systems indicate that [123I]-2-iodo-L-phenylalanine is a suitable tumor SPECT tracer candidate to evaluate and predict the individual patient response to radiotherapy.

Low grade myofibroblastic sarcoma of tongue: a case report.

A case of a 24-year-old woman with a 6 weeks lasting nodule of the right margin of the tongue is described. The nodule was 20 mm in diameter and showed surface ulceration. The diagnosis of low grade myofibroblastic sarcoma was supported by histological, immunohistochemical and electronmicroscopic examination. Although the tumor resection was not complete, the patient is free of disease 1 year after operation. The differential diagnostics of low grade myofibroblastic sarcoma is discussed.

Myofibrosarcoma of the nasal bone.

Myofibrosarcoma is a recently recognized rare tumor that mainly occurs in adults. These tumors are composed of a collagenous stroma and pleomorphic stellate to spindle-shaped cells that resemble smooth muscle cells with eosinophilic cytoplasm and tapered nuclei. We present a case of myofibrosarcoma of the nasal bones in a 4-year-old girl who showed rapid enlargement of a painless glabellar swelling. Computed tomography and magnetic resonance imaging revealed an expanding solid mass with erosion of the surrounding nasal bones. After excision and histopathological examination, this tumor was identified as a myofibrosarcoma. This is the first report of such a tumor localized to the glabellar region. This case report contributes to better awareness of an extremely rare type of glabellar lesion in children.

Characteristics and outcome of children with primary soft tissue sarcomas of extremities.

OBJECTIVES: To determine the characteristics and outcome or patients with primary soft tissue sarcomas of extremities in children. MATERIAL AND METHODS: Thirty-six patients treated for soft tissues sarcomas were enrolled into the study. Features analysed: the incidence of soft tissues sarcoma of extremities, the time from first clinical symptoms to making the diagnosis, the primary site of tumour; histopathologic type of tumour, stage of disease, methods and results of the treatment. RESULTS: The time From first symptoms to making the diagnosis was 5.4 months (mean). The site of the tumour was the femur in 6 patients, arm in 3, knee in 1. Histopathologic types: synovial sarcoma in 4 patients, malignant haemangiopericytoma in 2, rhabdomyosarcoma in 2, sarcoma myogenes in 1, primitive neuroectodermal tumour in l. Stage of disease: III deg. -- 8 patients, IV deg. -- 2. Patients underwent treatment according to the soft tissue sarcoma protocols. Results of treatment: first complete remission was observed in 7 patients; second complete remission in 1, one patient is on postoperative treatment. One patient died. CONCLUSIONS: 1. Combined treatment achieves full remission in the majority of patients with soft tissues sarcomas localized within the limbs. 2. In patients with large tumours (>5 cm) the treatment should to be started with inductive chemotherapy, and the surgery should be postponed. 3. Early excision of the tumour should be considered in cases of small tumours (< 5 cm), when resection with wide margin of healthy tissues is possible, without deteriorating the function of the limb or cosmetic damage.

[Malignant glial tumor with skeletal muscle differentiation. Description of a case]. / Tumore gliale maligno con differenziazione muscolare scheletrica. Descrizione di un caso.

A case of CNS gliomyosarcoma, in a 71-year-old female with skeletal muscle differentiation is presented. The tumor was composed by two cell types: one showed features typical of glial cells, the other was constituted by elements having immunohistochemical positivity with desmin, sarcomeric actin, myoglobin and myogenin antisera. It is postulated an origin from a cell capable of dual differentiation.