Soft Tissue Myxoma Research Articles

Mazabraud??s Syndrome with Sarcomatous Transformation: Scintigraphic and Radiologic Imaging

Abstract: Mazabraud's syndrome is an uncommon nonhereditary skeletal disease characterized by the association of fibrous dysplasia and soft tissue myxomas. Less than 50 cases have been reported in the medical literature and only a handful of them exhibited sarcomatous degeneration. The authors present an additional case of this rare osseous entity with malignant transformation diagnosed during imaging evaluation of a pathologic fracture of the right upper extremity.

MYXOMA OF ORAL SOFT TISSUE

The intraoral soft tissue myxoma or the peripheral myxoma is an extremely rare,slowly growing, benign mesenchymal tumor. Pathologically, it may be difficult todifferentiate from other tumors with myxoid stroma and is occasionally misinterpretedas malignant. We report a case of unusually massive peripheral myxoma of left alveolarridge in a 35-year-old lady.Key Words: Myxoma, peripheral, alveolar ridge.

Myxoma is not a single entity: a review of the concept of myxoma.

Myxoid lesions can be subdivided into (1) mainstream myxomas of soft tissues, (2) mainstream myxomas located outside the soft tissue, (3) inadequately substantiated myxomas, (4) myxoid soft tissue tumors or lesions not regarded as myxomas, (5) myxoid fatty conditions, (6) other soft tissue lesions and tumors that are sometimes markedly myxoid, (7) other soft tissue tumors in which myxoid foci may be seen, and (8) nonneoplastic myxoid conditions of soft tissue. More than 60 such conditions are listed and the five entities regarded as mainstream soft tissue myxomas (namely, intramuscular myxoma, juxta-articular myxoma, superficial angiomyxoma, aggressive angiomyxoma, and myxoid neurothekeoma [myxoma of nerve sheath]) are reviewed in detail. Intramuscular myxoma is exclusively intramuscular, usually affects middle-aged women, is most commonly located in the thigh, and does not recur after simple excision. Multiple intramuscular myxomas are rare and are usually associated with monostotic or polyostotic fibrous dysplasia and Albright's syndrome. Juxta-articular myxoma histologically resembles an intramuscular myxoma, but involves periarticular tendons, ligaments, joint capsules, muscles, and even the subcutis of adults. It may be associated with osteoarthritis of the adjacent joint. Some 30% recur locally. Superficial angiomyxoma also has been called cutaneous myxoma. It affects all ages, with a peak incidence in the third and fourth decades; arises in the trunk, lower limb, head, and neck regions; and usually measures less than 5 cm in diameter. Epithelial components are present in approximately 25% of tumors. Approximately one third recur locally, but there have been no metastases. Patients with multiple lesions may have the Carney complex. Aggressive angiomyxoma usually arises in the pelvic and perineal regions and affects females seven times as often as males. Tumors usually measure 10 cm or more in diameter, invade surrounding tissues, and recur in approximately 50% of cases. None have metastasized. Myxoma of nerve sheath (the myxoid variant of neurothekeoma) preferentially affects the dermis and subcutis of the cervicofacial areas and shoulders of young women. Most patients are younger than 40 years; one third of them are in the second decade of life. The majority of tumors measure between 0.5 and 1.5 cm. Only three of 102 cases compiled from the two largest published series recurred; none metastasized. The different clinicopathologic features and behavior of these five mainstream myxomas indicate that myxoma is not a single entity.

Multiple intramuscular myxomas associated with polyostotic fibrous dysplasia

Intramuscular myxoma is one of the rare but important associations of skeletal fibrous dysplasia. The association has been seen most frequently with polyostotic fibrous dysplasia, and occurs years after fibrous dysplasia has presented in most cases. The clinical behavior and pathological appearance of soft-tissue myxoma are sometimes mistaken for myxoid liposarcoma. A case of multiple intramuscular myxomas of the bilateral hips and right thigh, associated with polyostotic fibrous dysplasia of the right tibia and right ribs is presented. sive ground glass lesions (Fig. l a). The right tibia presented a radiolucent lesion with marginal sclerosis in the proximal diaphysis and a radiolucency without marginal sclerosis in the metaphysis (Fig. lb). A

軟口蓋に生じた軟部組織粘液腫の１例

Soft tissue myxoma is a very rare neoplasm in the oral cavity and only 13 Japanese patients have been described in the literature between 1941 and 1995. This paper presents a case of soft tissue myxoma arising in the soft palate of a 51-year-old man. The lesion was treated by surgical excision under general anesthesia, and there have been no signs of recurrence as of about 10 years after the operation.

S100, alpha-smooth muscle actin and cytokeratin 19 immunohistochemistry in odontogenic and soft tissue myxomas.

To compare the expression of S100 protein, alpha-smooth muscle actin (alpha-SMA) and keratin 19 in odontogenic myxomas and non-odontogenic myxoid lesions. Formalin fixed, paraffin wax embedded tissue from seven odontogenic myxomas, three soft tissue myxomas, six hyperplastic myxoid dental follicles, two intramuscular myxomas, 12 cardiac myxomas, and seven normal dental follicles were examined immunocytochemically for S100 protein, alpha-SMA and cytokeratin 19 using the Streptavidin-biotin method. A minority of odontogenic myxomas (three of seven) were positive for S100 and the staining was of moderate intensity and in all myxofibroblasts. Soft tissue myxomas, normal dental follicles, intramuscular myxomas, and most enlarged myxoid follicles were negative. In the cardiac myxomas the cells forming cords and islands were positive in approximately half (seven of 12), but the dispersed stellate myxoblasts were positive in only two cases. A population of cells in all the odontogenic myxomas and hyperplastic dental follicles contained alpha-SMA, but such cells were sparse in cardiac myxomas and present in only four cases. Cytokeratin 19 was present in odontogenic epithelium of odontogenic myxoma and follicles. A minority of odontogenic myxomas, but not other oral myxoid lesions, may express S100 protein and this could cause difficulty distinguishing myxoma from myxoid nerve sheath tumours. Sparse myofibroblastic cells occurred in all types of myxoma tested. The epithelium sometimes found within jaw myxomas expresses cytokeratin 19 and this is consistent with an odontogenic origin.

Soft-Tissue Myxomas and Fibrous Dysplasia of Bone

An association between fibrous dysplasia and myxomas (soft-tissue neoplasms of mesenchymal origin) has been described in the literature. The authors report another such case of fibrous dysplasia/myxoma coexistence: a patient with polyostotic fibrous dysplasia who developed right anterior thigh pain from a solitary intramuscular myxoma. After a thorough review of the literature, the authors found that a causal relationship between fibrous dysplasia and myxomata remains uncertain. To ensure an adequate and accurate diagnosis, however, patients with soft-tissue myxomas should be thoroughly evaluated for fibrous dysplasia. A proper investigation of soft-tissue masses also should be carried out to exclude malignancy.

Immunohistochemical evaluation of oral myxoid lesions

Oral examples of neurothekeomas (nerve sheath myxomas), soft tissue myxomas, and focal mucinous and odontogenic myxomas were examined for selected markers. With the use of avidin-biotin complex staining procedures, these specimens of lesions were stained with antibodies to S-100 protein, neurospecific enolase, neurofilaments, desmin, and vimentin. Our results show that the use of immunohistochemical markers for these neural antigens can aid in distinguishing nerve sheath myxomas from other oral myxoid lesions.

Intraspinal Neurothekeoma (nerve sheath myxoma): A Report of Two Cases

Neurothekeomas (nerve sheath myxomas) are rare benign cutaneous tumors. The authors describe two spinal intradural cases that show histologic, immunohistochemical, and electron microscopic features identical to their cutaneous counterparts. The authors' findings suggest histogenesis from Schwann's cells or undifferentiated nerve sheath precursor cells. Neurothekeomas in unusual locations should be differentiated from myxoid neurofibromas, perineuriomas, and soft tissue myxomas.

Multiple Myxomata of Soft Tissue Associated with Polyostotic Fibrous Dysplasia

Polyostotic fibrous dysplasia with associated myxomata of soft tissue has been reported rarely. In most cases, the patient appears first with fibrous dysplasia and many years later presents with soft-tissue tumors. This is a report of a 57-year-old woman--an unusual case of soft-tissue myxomas with fibrous dysplasia. This case suggests that a patient developing myxomatous tumors of the soft tissues might be evaluated for the possibility of associated fibrous dysplasia.

Osteogenic Sarcoma and Soft Tissue Myxoma in a Patient with Fibrous Dysplasia and Hemoglobins J Baltimore and S

A 41-year-old man with recognized polyostotic fibrous dysplasia since late childhood developed fibroblastic osteogenic sarcoma in the left tibia. Four months after the initial diagnosis, an intramuscular myxoma was discovered in the left thigh. Twenty years previously he had been found to be heterozygous for hemoglobins JBaltimore and S. Malignant transformation in fibrous dysplasia is unusual and may be associated in some individuals with prior irradiation. Soft tissue myxomas associated with fibrous dysplasia are even rarer. To the best of the authors' knowledge the occurrence of both of these lesions in a patient with fibrous dysplasia has been reported only once before. Patients with both fibrous dysplasia and myxomas may be at greater risk for malignant transformation than are individuals with only one of these lesions. There is no well-recognized association between hemoglobinopathies and either fibrous dysplasia or bone tumors. It is therefore probable that the rare constellation of findings is in this patient a stochastic event.

Intramuscular myxoma of the masseter

Soft tissue myxomas represent a distinctly uncommon type of benign mesenchymal neoplasm. They may rarely arise within skeletal muscle and are usually situated within the larger muscles of the extremities. The following report is of a case of myxoma arising within the muscles of mastication, of which we have been unable to discover a previous well-documented instance.

Myxomas of the paraoral-oral soft tissues

Fifteen cases of soft-tissue myxoma of the paraoral-oral structures have been presented. Eleven cases were garnered from an extensive review of the literature, and four previously unreported cases are described. The myxomas were slow-growing, insidious, infiltrative tumors which occurred in all age groups, with an average patient age of 38 years. Most frequent locations were the cheek, floor of the mouth, and palate. The lesions were present from 2 weeks to 6 years prior to treatment. In this series all the myxomas were treated by surgical excision, with no evidence of recurrences or metastases. The recommended therapy is surgical resection with adequate margins. Other myxomatous lesions which may mimic a myxoma are mentioned.

Oral focal mucinosis: A clinicopathologic and histochemical study of eight cases

Eight cases of the oral counterpart of cutaneous focal mucinosis and/or cutaneous myxoid cyst are reported, and their histologic and histochemical findings are discussed. On the basis of these findings, it is suggested that the lesions are identical and differ only in their anatomic location. It appears likely that most, if not all, cases diagnosed as oral soft-tissue myxomas are in reality oral lesions of the entity described as cutaneous focal mucinosis. It is postulated that focal mucinosis develops because of a fibroblastic overproduction of hyaluronic acid due to an unknown stimulus. The lesion is treated by surgical excision and has no tendency to recur.

Soft-tissue myxoma of the oral cavity: Report of a case

An extremely rare lesion—an intraoral soft-tissue myxoma of the lip—has been described. Myxomas are benign neoplasms of mesenchyme-like tissue, and they never metastasize. Surgical removal is the treatment of choice. If excision has been incomplete, recurrence is not uncommon.