Production of basement membrane laminin and type IV collagen by tumors of striated muscle: an immunohistochemical study of rhabdomyosarcomas of different histologic types and a benign vaginal rhabdomyoma

[Rhabdomyoma of the vagina. Case report and short literature review]

The differential diagnosis of vaginal polypoid masses should take rhabdomyoma into consideration even it is an extremely rare tumor. The present report describes a vaginal cystic mass located in the anterior wall of an asymptomatic, 38-year-old, Caucasian, nulliparous woman. Local excision and subsequent pathological examination were performed. The final diagnosis was vaginal rhabdomyoma. The literature is reviewed and differential diagnosis are discussed.

Localization of lymph capillaries and blood capillaries in human temporomandibular joint discs

The localization of lymph capillaries and blood capillaries in the human temporomandibular joint (TMJ) discs was examined immunohistologically with anti-human collagen IV antibody and anti-human von Willebrand factor in 26 human TMJ samples. The 16 internal derangement cases were then compared with the 10 normal control cases. The findings suggested that blood capillaries scarcely existed in all the fields of normal control TMJ discs (5/270, 1.9%) nor did lymph capillaries exist in the normal TMJ discs (0/270, 0%). New growth of blood capillaries had localized in all fields of the internal derangement discs specimens (113/378, 29.9%) and was concentrated in the lower area of the posterior part of the discs. The authors also observed a small distribution of lymph capillaries in all fields of this material (17/378, 4.5%). The new growth of lymph capillaries were always related to the blood capillary distribution and therefore their presence might be directly related to the capillary proliferation.

Immunohistochemical distribution of lymph capillaries and blood capillaries in the synovial membrane in cases of internal derangement of the temporomandibular joint

The distribution of lymph capillaries and blood capillaries in the synovial membrane was examined immunohistologically with anti-human collagen IV antibody and anti-human von Willebrand factor in 26 human temporomandibular joint (TMJ) samples comprising discs with adjoining synovial membrane from 10 control TMJs and from 16 TMJs with internal derangement. Three different distribution types were observed in the synovial membrane. In the control samples, the occurrence of blood capillaries and lymph capillaries was rare. In mildly hyperplastic synovitis, lymph capillaries were observed just beneath the surface of the synovial membrane, whereas blood capillaries occurred in a little deeper layer of the synovial membrane. In a severely hyperplastic synovitis, both lymph and blood capillaries were observed frequently. The present results suggest that the different distribution patterns of lymph capillaries and blood capillaries reflect the degree of synovitis but can not be attributed to specific clinical symptoms.

Local activity of matrix metalloproteinases in a case of botryoid sarcoma

The aim of the study was to assess the activities of the collagenases type IV (matrix metalloproteinase type 2 [MMP-2] and matrix metalloproteinase type 9 [MMP-9]), also known as gelatinases, and the local activity of interstitial collagenase (matrix metalloproteinase type I[MMP-1]) in tissue extracts from a case of the botryoid sarcoma, a rare and very malignant tumour of the female genital tract. Zymography revealed that botryoid sarcoma does not express the 92-kDa form of type IV collagenase activity in Triton extract and only weak activity in Heat extract when compared to values found in extracts from striated muscle and fibroma uteri. MMP-1 appeared in the latent form only in the Triton extract of botryoid sarcoma and its activity was lower than those found in the control tissues. These results indicate that the very rapid local invasion and systemic metastases associated with botryoid sarcoma do not depend on the activity of tumour-derived gelatinases.

Two cases of benign vaginal rhabdomyoma. Case reports

Two cases of benign vaginal rhabdomyoma, which occurred in women aged 38 and 54 years, are reported. The macroscopic and microscopic appearance is described. The literature on this rare tumour is reviewed and the differential diagnoses are discussed. Local excision is considered adequate treatment.

Extracellular matrix of small round cell tumors of childhood: an immunohistochemical study of 67 cases

Sixty-seven childhood tumors were studied immunohistochemically for the extracellular matrix element type IV collagen, laminin, and fibronectin. Tumors included Ewing's sarcoma, primitive neuroectodermal tumor, small cell osteosarcoma, neuroblastoma or ganglioneuroblastoma, rhabdomyosarcoma, and lymphoma. It was found that small cell osteosarcoma was often positive for fibronectin but not type IV collagen or laminin, a new observation. In the lymphomas, matrix proteins were rarely found. Ewing's sarcoma was variably positive for type IV collagen and laminin, but fibronectin was absent. Extracellular laminin and fibronectin were found in one of two cases of primitive neuroectodermal tumor. In neuroblastoma and ganglioneuroblastoma, the matrix components were rarely found. These results, discrepant with findings in cultured cells, may reflect the altered capacity of tumors to produce these proteins in vitro, which suggests that caution should be exercised in drawing conclusions regarding the nature or histogenesis of tumors from data obtained with cultured tumor cells. Embryonal rhabdomyosarcoma frequently contained all matrix elements in the extracellular space and in a dotlike pattern in the cytoplasm; alveolar rhabdomyosarcoma rarely contained these proteins and never exhibited the dotlike pattern. The frequent finding of matrix proteins in embryonal rhabdomyosarcoma but only rarely in alveolar rhabdomyosarcoma and the unique immunostaining pattern in embryonal rhabdomyosarcoma may prove to be a useful adjunct in the diagnosis of childhood tumors.

Carcinosarcoma of the oesophagus with rhabdomyoblastic differentiation

We report a case of oesophageal carcinosarcoma with prominent rhabdomyoblastic differentiation. Immunohistochemically, the rhabdomyblasts were mainly reactive to vimentin, cytokeratin, desmin, muscle-specific actin, myosin, and myoglobin, and were surrounded by laminin and type IV collagen-positive basement membranes. The tumour had dual differentiation, carcinomatous and sarcomatous, but also showed evident features of transition between the two components; suggesting a common origin. An epithelial-mesenchymal conversion could be the pathogenetic mechanism involved in the histogenesis of this lesion. The word carcinosarcoma, from a descriptive point of view, seems the most suitable to describe a tumour composed of both carcinomatous and true sarcomatous elements.

Expression of epithelial and extracellular matrix protein markers in meningiomas

In an attempt to characterize the dual mesenchymal and epithelial differentiating potential of meningiomas, cryostat sections from 50 meningiomas of diverse histological subtypes were examined immunohistochemically with a panel of markers for epithelial and mesenchymal differentiation. The overall positivities were: keratins 50%, epithelial membrane antigen 94%, human milk fat globules 38%, carcinoembryonic antigen 4% (secretory meningiomas only), desmoplakins 64%, collagen I 82%, procollagen I 96%, collagen III 74%, collagen IV 60%, laminin 54%, fibronectin 98% and vimentin 98%. Such production of keratins was not found in many previous immunohistochemical analyses of meningiomas with paraffin sections. The extracellular matrix proteins were present in a pericellular distribution suggestive of their being produced by the tumour cells. The potential of dual epithelial and mesenchymal differentiation in meningiomas was further examined in seven cases established on short-term cultures. Morphologically, subcultured tumour cells resembled fibroblasts and in five cases revealed similar epithelial and mesenchymal immunohistochemical profiles as for direct tumour immunostaining. In two cases, cells from the primary cultures revealed a fine skeleton of intercellular matrix proteins stainable by immunohistochemical methods, providing further proof that meningioma cells possess the capability to elaborate extracellular matrix proteins, a major mesenchymal function akin to that of fibroblasts.

Rhabdomyoma of the vagina

A case of vaginal rhabdomyoma in 35-year-old healthy woman is presented. The lesion, a pedunculated polyp measuring 1.2 cm in diameter, was located in the anterior wall of the vagina. This is an extremely rare entity that pursues a benign course. Light and immunohistochemical features are commented and selected literature briefly reviewed.

Differentiation dependent matrix formation (fibronectin and laminin) in an experimental murine rhabdomyosarcoma model

Cellular differentiation processes along with formation of extracellular matrix proteins were investigated in methylcholanthrene-induced murine rhabdomyosarcomata. We used primary tumours, allotransplants in nude mice, and the respective tumour recurrences generated by repeated incomplete surgical tumour removal. The expression of the differentiation markers desmin and myoglobin as well as the presence of fibronectin and laminin was ascertained by immunohistochemical methods. The question arises, whether or not correlations between the grade of cellular differentiation (desmin, myoglobin) and extracellular matrix formation (fibronectin, laminin) exist in tumours with striated muscle cell differentiation. The constant relations between cellular differentiation and matrix formation in original tumours also applied to allotransplants and tumour recurrences in which partially modulations of differentiation in comparison with original tumours could be recognized.

Alveolar soft part sarcoma. An immunohistochemical, cytologic and electron-microscopic study and a quantitative DNA analysis

The type, differentiation and histogenesis of the tumor cells of alveolar soft part sarcoma (ASPS) have been analyzed in a series of ten cases by a light-microscopic, ultrastructural, immunohistochemical and cytologic investigation and quantitative DNA analysis. Four tumors deviated from ordinary ASPS: three were wholly or partly of the so-called pleomorphic variant of ASPS and a fourth tumor showed calcifications of the psammoma body type. The ultrastructural findings and immunohistochemical demonstration of desmin supported the hypothesis of a rhabdomyomatous differentiation and gave no support to epithelial (negative immunoreactions for cytokeratins, epithelial membrane antigen, HMFG-1 and -2, tissue polypeptide antigen (TPA] or neuroectodermal (negative for S-100 protein, glial fibrillary acidic protein, neurofilaments) differentiation. The negative immunoreactions for vimentin and myoglobin and the positive reaction for neuron specific enolase (NSE) do not exclude a rhabdomyomatous differentiation since in rhabdomyosarcomas the undifferentiated rhabdomyoblasts generally contain vimentin and the differentiated tumor cells contain myoglobin and rhabdomyosarcoma has previously been reported as being positive for NSE. The production of external lamina material peripherally in the tumor cell nests and around vessels in the vascular septa was demonstrated both ultrastructurally and by immunohistochemistry using antibodies against collagen IV and laminin. The cytologic appearance in smears obtained by fine-needle aspiration from a case of the pleomorphic variant showed some resemblance to that of a carcinoma. The seven tumors with an ordinary cell appearance were found to show a diploid DNA-distribution at a quantitative analysis performed on paraffin sections, while the three tumors wholly or partly of the pleomorphic type showed an additional tetraploid peak.