Myxoid Tumor Research Articles

S-100 protein distribution in liposarcoma. An immunoperoxidase study with special reference to the distinction of liposarcoma from myxoid malignant fibrous histiocytoma.

The presence and distribution of S-100 protein were studied in 63 cases of liposarcoma and 20 cases of myxoid malignant fibrous histiocytoma (MFH), using the immunoperoxidase technique. Normal adipose tissue and benign lipomatous tumours were also studied by the same technique, for purposes of comparison. In all liposarcomas, most of the adipocytes and vacuolated lipoblasts were positive for S-100 protein, although the tumour cells in non-lipogenic areas of dedifferentiated liposarcoma and the non-vacuolated giant cells with a deeply eosinophilic cytoplasm in the pleomorphic liposarcomas were devoid of S-100 protein immunoreaction products. One third of the myxoid type liposarcomas contained numerous immunoreactive, immature-appearing spindle or oval cells, reminiscent of the primitive fat organs of white adipose tissue. Conversely, none of the myxoid MFHs contained S-100 protein in the tumour cells, including the irregularly vacuolated ones. These results suggests that the immunohistochemical demonstration of S-100 protein is a useful diagnostic tool, particularly for the assessment of vacuolated tumour cells and for the diagnosis of myxoid tumours.

LIPOSARCOMA

Fifty‐two cases of liposarcoma were analyzed clinicopathologically, and were grouped into the following five types: myxoid (28 cases), well‐differentiated (14 cases), pleomorphic (4 cases), round‐cell (3 cases), and mixed (3 cases). Three of the 28 myxoid tumors showed a pleomorphic pattern resembling that of the myxoid variant of malignant fibrous histiocytoma, and one of the 3 round‐cell tumors was considered to be a malignant counterpart of hibernoma. Ages ranged from 22 to 86 years with the average age of 49 years, the average patients with myxoid or round‐cell liposarcoma being over 10 years younger than those with well‐differentiated or pleomorphic liposarcoma. There was also a variation in the site of predilection of the cases: the great majority of myxoid type tumors occurred in the thigh, popliteal fossa and buttock (23 cases), while the majority of well‐differentiated type tumors were seen in the retroperitoneum (10 cases). The rate of local recurrence of the tumor was 46%. Four of the 5 well‐differentiated liposarcomas which recurred exhibited dedifferentiated pleomorphic components resembling those in malignant fibrous histiocytoma. The prognosis was more favorable in patients with ordinary myxoid tumors than in those with well‐differentiated tumors. The overall relative five‐year survival rate was 63%.

The myxoid tumors of somatic soft tissues

Tumors and tumorous conditions of superficial and deep soft tissues may owe their naked-eye appearance and much of their bulk to the accumulation of mucopolysaccharide material or, on rare occasions, to edema. The so-called myxoid tumors may be chondroblastic, fibroblastic, lipoblastic, myoblastic, or neurogenic. Benign and malignant tumors may be encountered. Naked-eye and microscopic appearances are described. Pseudotumors such as bursae, ganglia, cutaneous mucinoses, fasciitis, and myxoid cysts may enter the differential diagnosis. The value of accurate documentation is stressed. Histochemistry can make a limited contribution to diagnosis. The entities described have been examined with regard to alcian blue staining with and without pretreatment with hyaluronidase. Alcian blue staining in the presence of increasing concentrations of magnesium chloride has been investigated and found to be of value in the identification of tumors of chondroblastic origin.

Malignant Fibrous Histiocytoma

A clinicopathologic study of 130 cases of malignant fibrous histiocytoma (MFH) of the soft tissues is reported. This malignant neoplasm principally of middle and late adults occurred most often in the proximal portions of the extremities (48%) including the thigh and buttocks (35%). MFH may be subclassified into common (storiform and pleomorphic), myxoid, xanthogranu‐lomatous, and giant cell types, the common type being accounted for 100 cases (77%) of the series. The prognosis was more favorable in patients with storiform and myxoid tumors than in patients with pleomorphic or other type tumors, the overall relative five‐year survival rate being 48%. The depth of the tumor also affected prognosis with a significantly lower survival rate in deeply situated tumors. The rate of local recurrence of the tumor was 48%. Because of incomplete informations, metastasis was confirmed in only 26 patients and was most frequently to the lung (73%). In addition, electron microscopic, histochemical and tissue culture findings in limited cases are presented, concerning the histogenesis of the MFH.

Myxoid tumours of soft tissue

Myxoid tumours of soft tissues can be classified into 3 groups: I. Those in which mucin is consistently found and frequently dominates the histological picture; II. Those in which mucin production is often minimal but is of diagnostic importance; III. Those in which mucin production is an inconstant feature or is of less diagnostic-importance than in the first two groups. The first group includes ganglia and related lesions, intramuscular myxoma, the myxoid variant of nodular fasciitis, plexiform myxoma, spindle cell lipoma, myxolipoma, benign lipoblastoma and benign lipoblastomasis. myxoid neurofibroma, the myxoid variant of dermatofibrosarcoma protuberans, myxoid liposarcoma, extraskeletal myxoid chondrosarcoma, the myxoid variant of malignant fibrous histiocytoma, chordoma of soft tissues, myxopapillary ependymoma of soft tissues, and mucin secreting carcinoma metastatic to soft tissues. Eight cases of plexiform myxoma will be briefly reviewed. Plexiform myxomas are small, nodular or multinodular, solitary, intradermal and subcutaneous tumours which are commonest in the second and third decades. They have usually been noticed for several years before medical treatment is sought, they generally measure between 1 and 2 cm in diameter, arise both on the trunk and extremities but are often located on the hands. There is little evidence to suggest a relationship of plexiform myxoma to neural tumours or pacinian corpuscles. Plexiform myxoma appears to be benign. Myxoid tumours of soft tissues can be classified into 3 groups: I. Those in which mucin is consistently found and frequently dominates the histological picture; II. Those in which mucin production is often minimal but is of diagnostic importance; III. Those in which mucin production is an inconstant feature or is of less diagnostic-importance than in the first two groups. The first group includes ganglia and related lesions, intramuscular myxoma, the myxoid variant of nodular fasciitis, plexiform myxoma, spindle cell lipoma, myxolipoma, benign lipoblastoma and benign lipoblastomasis. myxoid neurofibroma, the myxoid variant of dermatofibrosarcoma protuberans, myxoid liposarcoma, extraskeletal myxoid chondrosarcoma, the myxoid variant of malignant fibrous histiocytoma, chordoma of soft tissues, myxopapillary ependymoma of soft tissues, and mucin secreting carcinoma metastatic to soft tissues. Eight cases of plexiform myxoma will be briefly reviewed. Plexiform myxomas are small, nodular or multinodular, solitary, intradermal and subcutaneous tumours which are commonest in the second and third decades. They have usually been noticed for several years before medical treatment is sought, they generally measure between 1 and 2 cm in diameter, arise both on the trunk and extremities but are often located on the hands. There is little evidence to suggest a relationship of plexiform myxoma to neural tumours or pacinian corpuscles. Plexiform myxoma appears to be benign.

Myxofibrosarcoma: a pathologico-anatomical, microangiographic and angiographic correlative study of eight cases.

A correlated angiographic, microangiographic and histological study of eight myxofibrosarcomas is presented. Myxofibrosarcoma is a very recently described type of malignant soft tissue tumour characterized by a mucoid and nodular appearance, predominantly arising superficially in the extremities and trunk in elderly people. Microscopically, the lobulated and myxoid tumours in the present series showed a characteristic plexiform network of fine capillary-like vessels and occasional wide, sinusoidal, angulated vessels. On plain radiographs they were all dense and well demarcated. Angiographically the tumours appeared highly vascular, with irregular tumour vessels often arranged in a patchy or nodular fashion. All revealed signs of a rapid circulation. The microscopic and angiographic appearances were correlated, in two cases utilizing microangiography. In the presence of a superficially located tumour with high density on plain radiographs, marked vascularity, patchy or nodular opacities, and signs of rapid circulation on angiogram one should suspect this diagnosis.

MYXOFIBROSARCOMA

A series of 30 myxofibrosarcomas is described. These malignant soft tissue tumours are characterized by a mucoid and nodular appearance, a coarse plexiform capillary pattern, and they are mostly seen subcutaneously (26 out of 30) in the extremities (24 out of 30) and trunk (4 out of 30) of elderly people. Histochemical studies, comprising staining with Alcian blue and toluidine blue at different pH's with and without preceding digestion with testicular hyaluronidase and with the Scott technique, indicated the presence of hyaluronic acid but not sulphated glycosaminoglycans as chondroitinsulphates. Myxofibrosarcoma is believed to belong to the general category of fibroblastic and histiocytic malignant soft tissue tumours. The median diameter of the tumours was 7 cm. They were divided into 4 grades according to cellularity, cell atypia and mitotic activity. The grade III and IV tumours showed pronounced atypia, often with bi‐ and multinucleated giant tumour cells and occasionally with giant cells of Touton's type, suggesting a relationship to malignant fibroxanthoma. All of the patients were treated surgically and one received also pre‐ and post‐operative irradiation. None of the 2 grade I myxofibrosarcomas recurred, while 2 out of 7 grade II tumours, 6 out of 10 grade III tumours, and 7 out of 11 grade IV tumours recurred once and up to 9 times. Metastasis appeared in 7 out of 30 patients; grade I tumours were not seen in any of these cases. By the time of follow‐up after intervals ranging from 1 month up to 27 years, 14 patients had died; 6 of these had died post‐operatively or of intercurrent disease. The differential diagnosis between myxofibrosarcoma and other myxoid soft tissue tumours is discussed.

Histochemical characterization of mucosubstances in bone and soft tissue tumors

The present investigation endeavors to characterize the mucosubstance content of 170 myxoid and chondromatous tumors and chordomas by histochemical methods. The results obtained using the critical electrolyte concentration (CEC) method as introduced by Scott and co-workers23,24 were compared with those obtained by staining with alcian blue and toluidine blue at different pH's with and without pretreatment with bovine testicular hyaluronidase. Tissues known biochemically to contain different heteroglycans were used as controls: synovial fluid and cock's comb (hyaluronic acid) stained with alcian blue up to a MgCl2 concentration of 0.1 M; fetal cartilage (chondroitin 4- and 6-sulphate) pulposus with notochordal remnants (keratan sulphate) up 10 1.0 M. The staining reaction of intramuscular myxoma and myxoid liposarcoma corresponded to that of synovial fluid and cock's comb (containing hyaluronic acid). Benign chondromatous tumors (osteochondroma, enchondroma, extraskeletal chondroma, chondromatosis in bursae, synovia, and tendon) as well as well-differentiated chondrosarcomas had a similar staining reaction to that of adult cartilage (containing keratan sulphate). However, the intensity of the reaction was lower in these tumors than in the adult cartilage, indicating that the keratan sulphate content of the tumors is lower. Most of the moderately well-differentiated chondrosarcomas, the poorly differentiated chondrosarcomas, and pulmonary metastases of chondrosarcoma, as well as mesenchymal chondrosarcoma and extra-skeletal chondrosarcoma possessed the same staining properties as fetal cartilage, known to contain chondroitin 4- and 6-sulphate but not keratan sulphate. A few of the moderately well-differentiated chondrosarcomas stained up to a MgCl2 concentration of 1.0 M. Three cases of poorly differentiated chondrosarcomas stained with alcian blue up to 0.35-0.45 M in the lowest differentiated areas, indicating the presence of sulphated heteroglycans, as chondroitin 4- and 6-sulphate. Most chordomas possessed the same staining properties as fetal cartilage; however, a few chordomas stained in the same way as notochordal remnants of nucleus pulposus (containing keratan sulphate), which are thought to be the origin of these tumors. The results of staining of the tumors in the present series with the Scott technique corresponds well with toluidine blue and alcian blue at different pH's with and without pretreatment of the sections with testicular hyaluronidase. Since bone and soft tissue tumors may contain varying mucosubstances depending on the tissue of origin and on differentiation, histochemical investigation of the heteroglycan content of these tumors may be a valuable diagnostic aid.

Ultrastructural Findings of a Rare Myxoid Tumor in a Case of Scleroderma

Scleroderma is a skin disease of unknown cause. The systemic form frequently begins peripherally, producing atrophy of the underlying fat and a thickening of the dermis. Tumors associated with scleroderma are distinctly uncommon. Only one other similar case has been alluded to in the literature.This patient presented with tumors 4mm to 3cm in size over the fingers and toes. The tumors were tense to touch although readily depressable without pain. A large tumor was removed surgically from the right index finger. Hematoxylin and eosin staining of paraffin sections revealed a normal appearing epidermis with slight thickening of the papillary dermis. The reticular dermis was edematous and contained sparse amounts of collagen with some fibroblast-like cells which were spindle-shaped and stellate. Histochemical stains showed a large quantity of amorphous material that was PAS positive, diastase-resistant and alcian blue positive at pH 4.

Aortic embolism due to myxoid tumour associated with myocardial calcification.

Aortic embolism due to myxoid tumour associated with myocardial calcification.