Search PubMed⌕ Search

Biomedical subjects

T Mentzel

Publications and source records attributed to T Mentzel.

At least 55 records · Page 3Linked to original sources
PubMed1999

Intravascular ("intimal") epithelioid angiosarcoma: clinicopathological and immunohistochemical analysis of three cases.

Angiosarcomas are rare malignant mesenchymal tumours, characterized morphologically by anastomosing vascular channels lined by atypical and proliferative active endothelial cells. An epithelioid cytomorphology of tumour cells is often seen focally in angiosarcoma, whereas purely epithelioid angiosarcomas are rare. Although angiosarcomas show a vascular differentiation they are almost never confined to pre-existing blood vessels. We describe three cases of intravascular epithelioid angiosarcoma arising in the carotid artery of a 60-year-old man, in the infrarenal part of the abdominal aorta and both renal arteries of a 69-year-old woman, and in the abdominal aorta of a 68-year-old man. In all cases malignant tumour tissue was found incidentally after disobliteration of thrombosed vessels. Histologically, purely epithelioid angiosarcoma composed of solid sheets of epithelioid tumour cells was seen; immunohistochemistry confirmed the endothelial differentiation of neoplastic cells. The reported cases show that angiosarcoma can occasionally arise within a pre-existing vessel.

Aged↗
PubMed1999

Intraneural angiosarcoma and angiosarcoma arising in benign and malignant peripheral nerve sheath tumours: clinicopathological and immunohistochemical analysis of four cases.

AIMS: Angiosarcomatous differentiation represents the least common form of heterologous differentiation in malignant peripheral nerve sheath tumours (MPNST), and is seen most frequently in patients with neurofibromatosis type 1. More rarely, it has been reported in patients without stigmata of neurofibromatosis, or in benign nerve sheath tumours and peripheral nerves. This study was undertaken to confirm this rare association. METHODS AND RESULTS: Four cases of angiosarcoma arising in a peripheral nerve, in a long-standing schwannoma and in two MPNST are described. Immunohistochemical studies were performed on paraffin sections with the alkaline phosphatase-antialkaline phosphatase method. An intraneural high-grade epithelioid angiosarcoma arose in the left posterior tibial nerve of a 78-year-old man, a well to moderately differentiated angiosarcoma was seen in an ancient schwannoma of the lateral neck in a 73-year-old women, and an angiosarcoma of varying grades of differentiation developed in a recurrent MPNST in the thigh of 38-year-old man. In addition a high-grade MPNST in the axillary region of a 30-year-old man showed foci of heterologous high-grade angiosarcomatous differentiation. The neural and endothelial lines of differentiation were confirmed in each case by positive immunohistochemical staining for neural and endothelial markers, respectively. In all cases tested, the neural differentiated cells stained immunohistochemically positive for antibodies against vascular endothelial growth factor. CONCLUSIONS: This study confirms the rare association of angiosarcoma arising in peripheral nerves, as well as in benign and malignant peripheral nerve sheath tumours.

Adult↗
PubMed1999

[Fibrolipomatous hamartoma of the nerve--a rare etiology of macrodactyly. A case report].

Fibrolipomatous hamartoma of nerve is a rare, tumor-like fibro-fatty growth arising from the epi- and perineurium. It mainly affects peripheral nerves and the median nerve in particular. An association with Klippel-Trenaunay syndrome and macrodactyly has been described. We present a 30-year-old patient, in whom the diagnosis of Klippel-Trenaunay syndrome had been made at the age of two, based on macrodactyly of the right hand. Because of increasing functional limitation and pain, the patient was referred to our department, after angiographic exclusion of Klippel-Trenaunay syndrome, for operative reduction of the tumor. Histologic examination revealed a fibrolipomatous hamartoma of the nerve. Further treatment consisted of surgical tumor reduction, which resulted in satisfactory recovery of function in the right hand. After eight months follow-up, the patient was able to perform all normal daily activities, and there was no evidence of recurrence of the lesion. Diagnostic evaluation of macrodactyly is necessary, since there may be an underlying cause such as fibrolipomatous hamartoma of a nerve, which if corrected early by surgical excision may prevent long-term disability.

Adult↗
PubMed1999

Hobnail hemangioma ("targetoid hemosiderotic hemangioma"): clinicopathologic and immunohistochemical analysis of 62 cases.

Hobnail hemangioma, also known as "targetoid hemosiderotic hemangioma", represents a distinctive, benign vascular tumor, characterized histologically by a biphasic growth pattern of dilated vascular structures in the superficial dermis lined by prominent hobnail endothelial cells, and collagen dissecting, rather narrow neoplastic vessels in deeper parts of the lesion. We analyzed the clinicopathologic and immunohistochemical features in a series of 62 cases. Patient age range was 6-72 years (median: 32 years); 34 patients were male and 25 female. Clinically, a broad variation of diagnoses ranging from hemangioma to dermal melanocytic nevus and fibrous histiocytoma was suggested. Nineteen tumors arose in the lower and 13 in the upper extremities, 12 on the back, 8 in the buttock and hip region, and one case on the chest wall. Follow-up information on 35 patients (range from 1 to 4 years; mean: 1.5 years) revealed no local recurrence nor systemic metastasis. All neoplasms were located in the dermis and showed a broad morphologic spectrum in dependence of the age of the lesions. In addition to lesions resembling cavernous lymphangioma or lymphangioma circumscriptum, neoplasms were seen with morphologic features reminiscent to retiform hemangioendothelioma, progressive lymphangioma and so-called Dabska's tumor. Immunohistochemistry performed in 28 cases showed positive staining of tumor cells for CD31 in all cases tested, whereas only 3 out of 28 cases stained completely positive for CD34. In addition 4 out of 8 cases stained positively for vascular endothelial growth factor receptor-3 (VEGFR-3). Neoplastic endothelial cells were surrounded by actin-positive pericytes in only 7 out of 27 cases tested. Hobnail hemangioma occurs more frequently in male patients and arises commonly in the extremities and the trunk. Histologic and immunohistochemcial features suggest a lymphatic line of differentiation for this distinctive vascular neoplasm.

Adolescent↗
PubMed1998

[Primary primitive neuroectodermal tumor of the urinary bladder. Clinicopathologic case report and differential small cell tumor diagnosis of this site].

We report a rare case of primary primitive neuroectodermal tumour of the bladder in an adult. A huge tumour with extensions into pelvic and retroperitoneal tissue was found radiologically in a 62-year-old man. The patient did not complain about remarkable clinical symptoms until 4 days before admission to hospital. Histology of diagnostic transurethral tumour resection showed a small round-cell tumour with focal necrosis and scattered Homer-Wright rosettes. Immunohistochemical analysis revealed that tumour cells stained positively with 013, a monoclonal antibody which recognizes the membrane glycoprotein p30/32MIC2. Focally, tumour cells stained positively for vimentin, NSE, S-100 protein and synaptophysin. The patient died 3 weeks later because of fulminant pulmonary embolism and autopsy revealed a huge, partly exophytic but mainly endophytic tumour of the bladder with extensions into the rectum and retroperitoneal tissue. The differential diagnosis of small round-cell tumours in this location is discussed.

Adult↗
PubMed1998

[Myofibroblastic tumors. Brief review of clinical aspects, diagnosis and differential diagnosis].

This review summarizes myofibroblastic tumours that have been characterized in the last years. These lesions include: fibromatoses in adults and infants (infantile digital fibromatosis and infantile myofibromatosis); myofibroma of adults, an almost exclusively solitary lesion in the skin which is characterized morphologically as a biphasic lesion composed of spindle-shaped eosinophilic tumour cells and more primitive mesenchymal tumour cells associated with a haemangiopericytoma-like vasculature; dermatomyofibroma (plaque-like dermal fibromatosis), a band-like myofibroblastic proliferation in young female patients, which is mainly located in the periaxillar region and in which distinction from more aggressive, plaque-like variant of dermatofibrosarcoma protuberans is mandatory; myofibroblastoma of the breast, a well-circumscribed lesion composed of spindle shaped, desmin-positive tumour cells, which is seen mainly in elderly male patients and has to be distinguished from other spindle cell lesions of the breast; angiomyofibroblastoma, a well-circumscribed myofibroblastic neoplasm of the vulva and vagina composed of avoid to round myoid tumour cells with scattered multinucleated cells, which forms a continuous morphological spectrum with the clinically more aggressive angiomyxoma in this location; intranodal myofibroblastoma, a distinctive proliferation of myofibroblastic cells associated with so-called amianthoid fibres, which is seen most commonly in inguinal lymph nodes; myofibroblastoma/myofibroblastic tumour of soft tissues, a variably well-circumscribed myofibroblastic lesion which lacks atypia and is composed of actin and/or desmin positive tumour cells, and poorly delineated sarcomas with myofibroblastic differentiation (myofibrosarcoma).

Adult↗
PubMed1998

Cutaneous angiosarcoma of the face: clinicopathologic and immunohistochemical study of a case resembling rosacea clinically.

An unusual cutaneous angiosarcoma resembling rosacea clinically is described. A 66-year-old man presented with a red discoloration and a diffuse swelling on his nose over a 2-year period that was diagnosed as rosacea. Despite antiinflammatory treatment, the infiltration increased and, after repeated skin biopsies, the diagnosis of a well-differentiated cutaneous angiosarcoma associated with a prominent inflammatory infiltrate was considered. The neoplasm was treated by surgery. The described case emphasizes that diffuse swelling and rosacea-like clinical features should be added to the variably clinical features of cutaneous angiosarcoma.

Aged↗
PubMed1998

Primary liposarcoma of the skin: a rare neoplasm with unusual high grade features.

Liposarcoma is the most common soft tissue sarcoma in adults. It presents in three main forms: well-differentiated liposarcoma (which includes adipocytic, sclerosing, inflammatory, spindle cell, and dedifferentiated subtypes), myxoid/round cell liposarcoma, and pleomorphic liposarcoma. Anatomic distribution depends largely on histologic subtype, but the deep soft tissue of the extremities and the retroperitoneum are most frequently affected. Whereas it is accepted that liposarcoma rarely occurs in the subcutaneous soft tissue, the dermis seems to represent an exceedingly rare site of occurrence. The clinicopathologic features of a series of seven primary cutaneous liposarcomas (two atypical lipomatous tumors/well-differentiated liposarcomas, one myxoid/round cell liposarcoma, and four pleomorphic liposarcomas) are analyzed here. Clinically, all of the patients were adults (four men, three women) with a median age of 72 years, and four of seven cases arose on the scalp. Local recurrences occurred in two patients, but no distant metastases or disease-related deaths have been observed. Although follow-up is relatively short, it appears that, exceptionally, liposarcoma occurs primarily in the skin and, despite an apparent tendency to show high-grade morphologic features, it seems to exhibit relatively indolent clinical behavior in this location.

Adipose Tissue↗
PubMed1998

Fibrosarcomatous ("high-grade") dermatofibrosarcoma protuberans: clinicopathologic and immunohistochemical study of a series of 41 cases with emphasis on prognostic significance.

The fibrosarcomatous variant of dermatofibrosarcoma protuberans (FS-DFSP) represents an uncommon form of DFSP, in which the prognostic influence of the fibrosarcomatous component is still debated. We analyzed the clinicopathologic and immunohistochemical features in a series of 41 patients. Patient age ranged from 8 to 87 years (median, 48 years), and 19 patients were female. Twenty five lesions were seen on the trunk, 6 on the upper limbs, and 4 on the lower limbs, and five neoplasms were located in the head/neck region; in one case, exact anatomic site was unknown. Twenty seven tumors involved purely dermal and subcutaneous tissues, in 10 cases, deeper structures were also involved, 1 case arose in the breast, and, in 3 cases, it was impossible to define exact depth of the lesion. Preoperative duration ranged from 1 month to 60 years (median, 3 years). Twenty six tumors were excised locally with clear margins, 7 were treated by wide excision, 3 by incomplete excision, and, in 4 patients, the lesion was shelled out. In one case, exact treatment was unknown. In addition, radiotherapy was administered in three cases and chemotherapy in one case. Histologically, the lesions showed areas of typical, low-grade DFSP adjacent to fibrosarcomatous areas. In four cases, a previously ordinary DFSP recurred as pure fibrosarcoma, in two cases, local recurrence of FS-DFSP showed features of ordinary DFSP. Fibrosarcomatous change was more common in the primary (de novo) lesions than in recurrent lesions (3.6:1). Proportion of fibrosarcoma varied between < 30% in 6 cases to > 70% of tumor tissue in 21 cases. An abrupt transition between both components was seen in 19 cases. The fibrosarcomatous component showed focal necrosis in seven cases and showed a higher mitotic rate in comparison with ordinary DFSP areas (mean, 13.4 versus 2.3 mitoses in 10 high-power fields). Additional histologic features included progression to pleomorphic sarcoma in 2 recurrent cases, melanin-pigmented cells (Bednar FS-DFSP) in 1 case, focal myxoid change in 13 cases, plaque or keloidlike hyalinization in 3 cases, and myoid bundles and nodules in 9 cases. Immunohistochemically, tumor cells in DFSP areas stained positively for CD34, whereas, in FS-DFSP areas, only 15 out 33 cases were positive for CD34. Follow-up in 34 of 41 patients (mean, 90 months; median, 36 months) revealed local recurrence in 20 patients (58%) (recurrence occurred in 5 patients on two or more occasions). Metastases (5 lung, 1 bone, and 1 soft tissue) were seen in 5 patients (14.7%), and 2 patients have died of tumor to date (5.8%). Necrosis, high mitotic rate (> 10 mitoses per 10 high-power fields), and presence of pleomorphic areas in FS-DFSP tended to be related with poor clinical outcome, but no statistically significant association was detected. Fibrosarcomatous change in DFSP represents a form of tumor progression in DFSP and is associated with a significantly more aggressive clinical course than in ordinary DFSP, indicating a possible need for treatment intensification in such cases.

Actins↗
PubMed1998

Atypical or worrisome features in cellular neurothekeoma: a study of 10 cases.

Cellular neurothekeoma is a recently characterized benign cutaneous neoplasm arising usually on the upper trunk or head and neck of children or young adults. Typical histology is that of a lobulated dermal tumor composed of spindle and epithelioid cells, arranged in fascicles and nests, lacking immunoreactivity for S-100 protein, but usually being NK1/C3 positive. We present 10 new cases of cellular neurothekeoma with atypical histologic features that have not been described previously and that suggested the possibility of malignancy. The age range of affected patients was 1 to 44 years (median, 20.5 years); sites included the head and neck (three cases), the upper limbs (two cases), the lower limbs (two cases), and the trunk (two cases). Atypical findings in individual cases included large size (up to 6 cm), deep penetration (extending into skeletal muscle or subcutaneous fat, or both), diffusely infiltrative borders, vascular invasion, high mitotic rate, and marked cytologic pleomorphism. Clinical follow-up was available in 7 of 10 cases. Although the atypical features raised concern about the biologic potential of these lesions, preliminary follow-up (1-5 years) has shown no recurrence and suggests that complete surgical excision of these lesions is curative. These new data expand the morphologic spectrum of cellular neurothekeoma.

Adolescent↗
PubMed1998

Low-grade myofibroblastic sarcoma: analysis of 18 cases in the spectrum of myofibroblastic tumors.

The clinicopathologic, immunohistochemical, and ultrastructural features of a seemingly distinctive low-grade spindle cell sarcoma showing myofibroblastic differentiation have been analyzed in a series of 18 patients. The age range of the patients (7 women and 11 men) was 19-72 years (median: 42 years). A painless, enlarging mass was the most common clinical presentation. Five tumors arose in the oral cavity (including four lesions in the tongue), four in the lower extremities and three in the upper extremities, four cases in the abdominal/pelvic cavity, and two on the trunk. Eight soft-tissue cases involved skeletal muscle, three cases were located in perifascial tissues, and two arose in subcutaneous tissue. Tumor size ranged from 1.4 to 17 cm (median: 4 cm); in six cases (of which four were abdominal/pelvic) the lesion was larger than 5 cm. All patients were treated surgically, and four received additional adjunctive therapy. Histologically, most cases were cellular lesions showing a diffusely infiltrative pattern, and were composed of spindle-shaped tumor cells arranged mainly in fascicles. Tumor cells had poorly defined, palely eosinophilic cytoplasm and fusiform nuclei, which were either tapering and wavy or plumper and vesicular with indentations and small inconspicuous nucleoli. Tumor cells were set in a collagenous matrix often with prominent hyalinization. Mild nuclear atypia was noted in 16 cases; in the other 2 cases, and in the metastases of one other lesion, a greater degree of nuclear atypia was seen. In all but one case, the mitotic rate ranged from 1 to 6 mitoses in 10 HPFs (mean: 2/10 HPFs); in a single case, there were more than 20 mitoses in 10 HPFs. Immunohistochemically, all cases stained positively for at least one myogenic marker; 12 cases were positive for desmin, 11 for alpha-smooth muscle actin, and 6 for muscle actin (HHF35). Seven neoplasms were desmin positive/ alpha-smooth-muscle actin negative, and five cases were desmin negative/alpha-smooth-muscle actin positive emphasizing the variable immunophenotype of myofibroblastic lesions. In addition, 7 of 10 tumors stained at least focally positive for fibronectin. Ultrastructural examination in five cases showed characteristic features of myofibroblasts. Follow-up in 11 patients (median: 29 months) revealed local recurrence in 2 cases, and multiple distant soft-tissue, intraosseous, and pulmonary metastases in one other patient. Low-grade myofibroblastic sarcoma seems to represent a distinct entity in the spectrum of low-grade myofibroblastic neoplasms and is distinguishable from fibromatosis, myofibromatosis, solitary fibrous tumor, fibrosarcoma, and leiomyosarcoma.

Actins↗
PubMed1998

[Hemangioendotheliomas--evolution of a concept of a heterogeneous group of vascular neoplasms].

The term haemangioendothelioma has been used in the past for a number of vascular lesions, which vary not only by their morphological features, but more importantly, also by their biological behavior. In the recent WHO-classification of mesenchymal tumours haemangioendotheliomas have been defined as vascular tumours of "intermediate" or "borderline" malignancy, and spindle cell haemangioendothelioma (SHE), epithelioid haemangioendothelioma (EHE), and rare malignant endovascular papillary angioendothelioma (Dabska's tumour) were included in this category. To this list might be added the more recently delineated kaposiform (KHE), retiform (RHE), polymorphous (PHE), and composite haemangioendothelioma (CHE). Although very popular, the concept of "borderline" or "intermediate" malignancy encompasses a wide variety of clinical situations, prognosis, and biological behavior. Therefore uncritical use of the term haemangioendothelioma represents a potential source of confusion to patients and oncologists, and it should not be used without further clarification. SHE was originally described as low-grade angiosarcoma, however, the study of large series with expanded follow-up information clarified that these lesions are often multicentric in one anatomic region, whereas true recurrences are rather rare, and systemic metastases and tumour progression do not occur. Therefore redesignation of these lesions as spindle cell haemangioma has been proposed. EHE of skin and soft tissues represents a distinctive vascular neoplasm characterized by nests and cords of epithelioid endothelial tumour cells with characteristic cytoplasmic vacuoles, which are set in a myxohyaline matrix. The reported rates of systemic metastases (20-30%), and tumour related death of patients (13-17%) in EHE, and the occurrence of multicentric EHE argue against the classification of EHE as a low-grade or "borderline" malignant neoplasm; EHE should be better regarded as a clearly malignant vascular tumour (G2). Although it seems that KHE is associated with a high mortality rate, the deaths are almost always related to locally invasive effects or as result of bleeding and consumption coagulopathy. So far no metastasizing case of KHE has been reported, and it seems that the prognosis in KHE is mainly related to size, anatomical site and depth of the lesion. KHE should be classified as a locally aggressive, non-metastasizing vascular tumour. The remaining entities (RHE, Dabska's tumour, PHE, and CHE) are characterized by an infiltrative growth, a high rate of (often repeated) local recurrences, and a definitive risk of metastases. Therefore these lesions fulfil criteria for low-grade malignant vascular neoplasms.

Diagnosis, Differential↗
PubMed1998

[Cutaneous neural neoplasms--an update].

Until recently, benign cutaneous neural tumours which do not fulfill criteria for either neurofibroma or schwannoma often were lumped into the broad category of benign peripheral nerve sheath tumours (PNST). However, during the last years a number of new entities of neural tumours has been described, and advances in immunohistochemistry and electronmicroscopy have helped us better to understand the cytological differentiation in these neoplasms. The knowledge of these distinctive neoplasms is necessary in order to avoid diagnostic pitfalls and misdiagnosis of more aggressive neoplasms. These distinctive lesions include: Neurothekeoma, which can be divided into classical myxoid and cellular types showing characteristic histological and immunohistochemical features. Typical neurothekeoma (nerve sheath myxoma) is a lobular or nodular dermal neoplasm composed of plump spindled or stellated S-100 positive tumour cells set in a myxoid stroma. In contrast cellular neurothekeoma is characterized as an ill-defined dermal neoplasm composed of concentric nests and fascicles of spindle-shaped and epitheloid tumour cells, which are S-100 negative but stain positively for NKIC3. The evidence of intermediate forms of neurothekeoma showing features of ordinary, hypocellular neurothekeoma and cellular neurothekeoma, as well as ultrastructural studies emphasize, that both variants represent a spectrum of neurothekeoma. Solitary circumscribed neuroma ("palisaded encapsulated neuroma") manifests mainly as a skin-colored or pink papule or nodule, and is most often located on the face. Histologically, solitary circumscribed neuroma is a well-circumscribed round or ovoid dermal neoplasm composed of interwoven fascicles of schwann cells, which stain positively for S-100 protein, and numerous neurofilament positive axons surrounded partly by fibroblasts and EMA-positive perineurial cells. Perineurioma is a rare well-circumscribed neoplasm which occurs mainly in subcutaneous tissue and only rarely in the dermis and in deep soft tissue. Perineurioma is composed of elongated bipolar spindle-shaped tumour cells which are arranged in a storiform, linear or lamellated growth pattern. The tumour cells stain positively for vimentin and EMA, and for CD34 in a number of cases, but lack positivity for S-100 protein, neurofilament and desmoplakin. In addition unusual forms of schwannoma including cellular schwannoma, solitary plexiform schwannoma, and melanocytic schwannoma are briefly discussed.

Humans↗
PubMed1997

Molecular abnormalities of the p53 pathway in dedifferentiated liposarcoma.

Dedifferentiated liposarcoma represents a distinct subtype of liposarcoma and is characterized by the presence of abrupt transition from well-differentiated liposarcoma to high-grade pleomorphic sarcoma (mostly MFH-like). A key role for p53 in tumour progression of this subset of liposarcomas has been suggested on the basis of p53 immunopositivity. A series of 14 dedifferentiated liposarcomas has been investigated by analysing the p53 gene and protein together with the p53-related molecules p21Waf1 and mdm2, to verify whether the p53 pathway is involved in the development and progression of this tumour type. The results indicate that the p53 gene is rarely involved in dedifferentiated liposarcoma (7 per cent of cases analysed) and that low percentages of p53 immunopositivity are still compatible with integrity of the p53 gene. This concept is also supported by the observed preservation of p21Waf1 immunoreactivity in all but the p53-mutated cases. By contrast, mdm2 overexpression emerges as the most frequent abnormality in dedifferentiated liposarcoma (57 and 78 per cent of cases in well-differentiated and high-grade areas, respectively).

Cell Differentiation↗
PubMed1997

[Intramural hemangioma of the portal vein].

Capillary hemangiomas occur rather ubiquitously, but extremely rare within the wall of blood vessels. For this reason the authors report on a small capillary hemangioma of sinusoidal type. It has been observed fortuitously within the wall of the portal vein at autopsy of a 79-year-old woman. Based on site and structural characteristics the benign neoplasia is supposed to have developed from a local malformation, probably an abortive liver anlage.

Aged↗
PubMed1997

[Retiform hemangioendothelioma. Clinico-pathologic case report and discussion of the group of low malignancy vascular tumors].

We report a locally recurrent retiform haemangioendothelioma (RHE) on the right great toe in a 40-year-old woman. There was a secondary soft tissue lesion on her right lower leg. Histologically, primary lesion, local recurrence and the secondary soft tissue lesion (soft tissue metastasis?) showed identical features. Long, arborizing, neoplastic blood vessels were lined by CD31 and factor VIII-positive, monomorphic endothelial tumour cells; focally solid tumour areas, papillae and a prominent inflammatory infiltrate consisting of mature B and T lymphocytes were noted. The concept and the group of low-grade malignant vascular neoplasms is discussed, with special emphasis on inclusion of RHE in this category.

Adult↗