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T Mentzel

Publications and source records attributed to T Mentzel.

At least 73 records · Page 4Linked to original sources
PubMed1997

Solitary fibrous tumour: clinicopathological, immunohistochemical, and ultrastructural analysis of 12 cases arising in soft tissues, nasal cavity and nasopharynx, urinary bladder and prostate.

The clinicopathological features of 12 extraserosal solitary fibrous tumours (SFT) are described. The age of the patients ranged from 18 to 72 years (mean: 48.2 years; median: 54 years); 5 were female patients. Seven lesions arose in soft tissue (5 in perifascial, and 1 each in subcutaneous and intramuscular tissues). They were situated in the groin (2 cases) and the neck, right buttock, left scapula, upper arm, and anterior abdominal wall (1 case each). One polypoid lesion was seen in in the nasal cavity and 1 in the nasopharynx; 2 neoplasms arose in the urinary bladder and 1 was located in the prostate and periprostatic tissue. Nine lesions were excised; in 1 patient wide excision was performed and in 2 patients, transurethral resection. Limited follow-up of 3 cases revealed a benign clinical course. The size of the neoplasms ranged from 1.7 cm to 20.0 cm (mean: 5.4 cm; median: 3.5 cm). Histologically, the neoplasms were well circumscribed and composed of cytologically bland spindle cells arranged without an obvious pattern; focally storiform or fascicular growth patterns were seen. Tumour cells were separated by thick bands of collagen demonstrating foci of keloid-like hyalinization. Prominent vascularity showing a haemangiopericytoma-like vascular pattern and vessels with thick, hyalinized vessel walls were seen in all cases. Increased mitotic activity was noted in 2 soft tissue cases (4-6 mitoses in 10 high-power fields); the other cases showed fewer than 2 mitotic figures in 10 highpower fields. Immunohistochemically, all cases tested stained positively for vimentin, CD34 and CD99, and 2 cases showed focal myofibroblastic differentiation. Two cases examined ultrastructurally showed a fibroblastic phenotype; focally pinocytic vesicles and microfilaments were identified. SFT represents a distinct neoplasm that should be included in the differential diagnosis of spindle-cell neoplasms in soft tissue, nasal cavity and nasopharynx, urinary bladder, and prostate. Strict diagnostic criteria are necessary to avoid overdiagnosis or confusion with more aggressive neoplasms in these locations.

Adolescent↗
PubMed1997

Solitary fibrous tumor of urinary bladder: report of two cases.

The clinical and pathologic features of two cases of solitary fibrous tumor arising from urinary bladder wall are described. To our knowledge, solitary fibrous tumors have not been previously reported at this site. Both tumors showed typical histologic features of solitary fibrous tumor, were CD34 immunostain positive and pursued a benign clinical course on short term follow-up.

Diagnosis, Differential↗
PubMed1997

Dedifferentiated myxoid liposarcoma: a clinicopathological study suggesting a closer relationship between myxoid and well-differentiated liposarcoma.

Myxoid/round cell liposarcoma is arguably the commonest type of liposarcoma occurring in the extremities and may show gradual progression from low-grade, pure myxoid liposarcoma to high-grade round cell liposarcoma. Rarely myxoid/round cell liposarcoma is associated with areas of well-differentiated or pleomorphic liposarcoma (mixed liposarcoma). We describe the clinicopathological features of three unusual myxoid/round cell liposarcomas which showed morphological features of de novo dedifferentiation. All patients were male and were aged 66, 70 and 76 years, respectively. One lesion each arose in the retroperitoneum, inguinal region and peritoneal cavity. Histologically, in one case the myxoid/round cell component was juxtaposed to a high-grade non-lipogenic component resembling non-pleomorphic storiform 'malignant fibrous histiocytoma' ('MFH'), one case showed a combination of myxoid liposarcoma and a high-grade myxofibrosarcoma-like component (so-called myxoid 'MFH'), and in the third case, a well-differentiated myxoid liposarcoma with a discontinuous micronodular pattern of dedifferentiation was seen. Follow-up information of 30, 28 and 26 months revealed two recurrences each in two patients. These patients died of postoperative pulmonary embolism and abdominal haemorrhage, respectively; systemic metastases were not noted. These cases demonstrate that myxoid/round cell liposarcoma can show, albeit very rarely, histological features of dedifferentiation. Cases like these, combined with the occurrence of mixed-type liposarcoma (well-differentiated/myxoid liposarcoma) and the vicinity of chromosomal regions involved by specific karyotypic aberrations in these tumours, suggest that myxoid/round cell liposarcoma and well-differentiated liposarcoma (including its dedifferentiated variant) are more closely related in biological terms than is generally believed.

Abdominal Neoplasms↗
PubMed1997

Kaposiform hemangioendothelioma in adults. Clinicopathologic and immunohistochemical analysis of three cases.

Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm that previously has been described only in children. We report three cases occurring in adults. The patients, two men and one woman, were aged 64, 55, and 48 years, respectively. Lesions arose on the chest wall, the lateral aspect of the neck, and in the groin and buttock, and each was situated in superficial soft tissue. Tumor size ranged from 0.9 to 7 cm. Histologically, in all cases a lobular or nodular growth pattern of densely packed spindle-shaped tumor cells closely associated with small slitlike and sievelike blood vessels was seen. Within one lesion, small nodules of plumper, epithelioid tumor cells were identified. Well-formed capillaries frequently containing fibrin thrombi were observed mainly in the periphery of tumor nodules. Areas of hemorrhage and hemosiderin deposits were observed in two cases. Associated lymphangiomatosis composed of diffusely infiltrating lymphatic spaces of the dermis and subcutis was present in one case. Nuclear atypia was minimal in all cases, and mitotic figures were rare in two cases; in one case up to 6 mitoses in 10 high-power fields were noted focally. Immunohistochemically, well-formed capillaries stained positively for all the vascular markers used; however, endothelial cells lining the small slitlike and sievelike vascular spaces did not stain for von Willebrand factor. At least focally, actin-positive pericytes were seen. Neoplastic spindled cells stained only focally for CD34 and CD31. Two lesions were excised with clear margins; in one case only repeated biopsies were done. Follow-up information between 14 and 28 months revealed no sign of recurrence or metastasis. In adults, the differential diagnosis of KHE comprises especially Kaposi's sarcoma and spindle cell hemangioendothelioma; further differential diagnoses include tufted hemangioma and cellular capillary hemangioma, which occur rarely in adults.

Actins↗
PubMed1997

Epithelioid hemangioendothelioma of skin and soft tissues: clinicopathologic and immunohistochemical study of 30 cases.

Epithelioid hemangioendothelioma of soft tissues (EHE) represents a distinct entity with an unpredictable clinical course. We analyzed the clinicopathologic and immunohistochemical features in a series of 30 patients. Patient age range was 16-74 years (median 50); 18 of 30 patients were female. Eight tumors arose in the lower and two in the upper extremities, seven on the trunk, five each in the head/ neck and anogenital regions, two in the mediastinum, and one in the abdomen. Seventeen neoplasms were located in deep soft tissues, nine were subcutaneous or perifascial, and four were dermal; size ranged from 0.4 to 10 cm; in 11 cases the tumor was > 5 cm. Tumors with an infiltrative growth pattern were more common than entirely circumscribed lesions. The tumors were composed histologically of short strands, cords, or small clusters of epithelioid, round, to slightly spindled endothelial cells that formed at least focally, intracellular lumina and were set in a frequently myxohyaline stroma. Thirteen of 30 lesions showed angiocentric growth, which was occlusive in many cases. Immunohistochemically, all cases tested were positive for at least one endothelial marker (CD31, CD34, factor VIII, Ulex europaeus), six of 23 (26%) were positive for cytokeratin, and five of 11 (45%) were positive for alpha-smooth muscle actin. Median follow-up of 36 months (range 2-96) in 24 cases showed local recurrence in three cases and systemic metastases in five cases (21%); four patients (17%) died of tumor. Although more aggressive histologic features (striking nuclear atypia in eight cases, numerous spindled cells in 10, more than two mitoses per 10 high-power fields in nine, and small, more solid angiosarcomalike foci in four cases) tended to be related to poor clinical outcome, there was no clear correlation. Two metastasizing cases showed no histologically atypical features whatever. We suggest that EHE of soft tissue is better regarded as a fully malignant, rather than borderline, vascular neoplasm, albeit the prognosis is better than in conventional angiosarcoma.

Adolescent↗
PubMed1997

Ancient hematoma: a unifying concept for a post-traumatic lesion mimicking an aggressive soft tissue neoplasm.

We describe the clinicopathologic features of four cases of ancient hematoma occurring in the tensor fascia lata and perifascial tissue that clinically and radiologically mimicked aggressive soft tissue neoplasms. The lesions arose in three men and one woman, aged between 31 and 61 years. In three cases, an injury to the affected site had been noted 18 months, 19 years, and 20 years beforehand, respectively. At presentation, these deep-seated and enlarging lesions were highly suggestive of soft tissue sarcomas. Three lesions were treated by excision of an intramuscular or perifascial mass; in one case, repeated incomplete excisions were performed. Grossly, in three cases a well-circumscribed, fusiform mass with a soft cystic center and a fibrous pseudocapsule was described. Histologically, blood clot, fibrin, and predominant amorphous debris were seen in the central cavities; in three cases, the fibrous pseudocapsule contained clumped, eosinophilic, amorphous debris surrounded by a prominent xanthogranulomatous inflammatory infiltrate with numerous, multinucleated, foreign body-type, giant cells. Additionally, cholesterol clefts, areas of hemorrhage and dystrophic calcification, hemosiderin deposits, and cellular scar tissue were seen. Follow-up information revealed no evidence of recurrence or secondary infection in the three cases treated by local or wide excision; in the case in which incomplete excision was performed, continuous symptomatic growth was noted. Pathologic features of ancient hematomas are similar, if not identical, to those hematomas described previously as calcific myonecrosis, chronic expanding hematoma or posttraumatic cyst of soft tissues; we propose instead the term ancient hematoma. The reason for the commonly very long delay between the initiating trauma and presentation is uncertain.

Adult↗
PubMed1997

Schwannomas of the sinonasal tract and nasopharynx.

Approximately 45% of benign peripheral nerve sheath tumors occur in the head and neck region. Of these, schwannomas (neurilemomas) arising from the nasal cavity and paranasal sinuses account for less than 4%. Pathologic features of this subset are not well documented. We report a series of five cases of sinonasal schwannoma and one in the nasopharynx. The male-to-female ratio was equal, and the age at presentation ranged from 38 to 65 years of age (median, 52 yr). Four of the lesions were located within the nasal cavity, one arose from the maxillary sinus, and one originated in the nasopharynx, with extension into the Eustachian tube. Two cases showed local bony destruction, with intracranial extension. Presenting clinical symptoms included nasal obstruction, epistaxis, rhinorrhea, anosmia, facial swelling, headache, and serous otitis media; the two cases with intracranial spread also presented with visual disturbances. All of the six cases were treated by surgical excision. Clinical follow-up in five cases ranged from 6 to 48 months (median, 27 mo). Histologically, all of the lesions shared many cytomorphologic features common to schwannomas arising at other sites, and all of the six cases showed strong, diffuse immunoreactivity for S-100 protein. Four cases showed features of the cellular variant, and one showed focal granular cell change. An unusual and previously poorly documented histologic feature, distinct from schwannomas arising at most other anatomic sites, was a lack of encapsulation, which, when combined with hypercellularity, often raised suspicion of malignancy. Because none of the cases in this series has shown either local recurrence or postoperative metastasis to date, lack of encapsulation and locally destructive growth in an otherwise histologically typical schwannoma arising at this site should not suggest malignant potential.

Adult↗
PubMed1997

Molecular aberrations of the G1-S checkpoint in myxoid and round cell liposarcoma.

Myxoid and round cell liposarcoma represents a morphological spectrum in which tumor progression from low-grade myxoid to high-grade round cell areas is frequently observed. A distinctive t(12;16)(q13;p11) reciprocal translocation rearranges the CHOP gene localized to 12q13 in most cases. Data concerning the occurrence of cell cycle aberrations in this subset of mesenchymal malignancies are very limited. Therefore, we analyzed a histologically homogeneous series of 21 cases of myxoid and round cell liposarcoma. The p53 pathway was studied by investigating the TP53 gene and protein, mdm2 protein, and p21Waf1 protein. The Rb-cyclin D pathway was analyzed by studying the pRb protein, the p16MTS1 gene, cyclin D1, cyclin D3, p27Kip1, cdk4, and cdk6 proteins. In contrast with the rare involvement of the TP53 gene in well differentiated liposarcoma, aberrations of the TP53 gene were observed in approximately 30% of cases of myxoid and round cell liposarcoma. Notably, mdm2 overexpression was seen in 56% of cases and correlated with histological grade, therefore indicating a possible role in tumor progression. Abnormalities involving the Rb-cyclin D pathway were observed in more than 90% of cases. pRb loss was present in one-third of cases and, at variance with that observed in other subsets of sarcoma, overexpression of cyclin Ds represented a rare event. Interestingly, upregulation of either cdk4 or cdk6 was demonstrated in 85% of cases.

Chromosome Aberrations↗
PubMed1996

[Tufted hemangioma. Clinicopathologic and immunohistologic analysis of 5 cases of a distinct entity within the spectrum of capillary hemangioma].

Two female and three male patients with acquired "tufted angioma" are presented. The age of these patients ranged from 10 to 62 years. Two lesions were sited in the head and neck region, two in the upper extremities, and one on the trunk. Clinically, the angiomatous lesions appeared as elevated plaques, flat lesions with papular and macular areas, or erythematous plaques with small nodules. In four cases a biopsy was done, and in one case the tumour was excised. Histologically, the neoplasms were characterized by irregularly distributed vascular tufts in the dermis, and, in one case, in the upper subcutis. The vascular tufts were composed of plump endothelial cells and spindle-shaped pericytes surrounded by crescent-shaped vascular spaces. The positive staining for CD 31 and for CD 34 and alpha-smooth muscle actin, and the negative staining of endothelial cells for factor VIII underline both the existence of two cellular components in tufted angioma and the immaturity of endothelial cells. Evidence of regular mitotic figures in two cases and increased proliferative activity in three out of four cases tested, emphasize the neoplastic nature of slowly growing tufted angioma. Benign tufted angioma is a distinct entity in the spectrum of capillary haemangiomas and must be distinguished from other vascular neoplasms.

Actins↗
PubMed1996

[Low malignancy myxofibrosarcoma versus low malignancy fibromyxoid sarcoma. Distinct entities with similar names but different clinical course].

Low-grade myxofibrosarcoma (MFS) and low-grade fibromyxoid sarcoma (FMS) are two distinct entities in the spectrum of myxoid mesenchymal sarcomas with fibroblastic differentiation. Low-grade MFS is seen often in the extremities of elderly patients, subcutaneously more frequent than in deep soft tissues, whereas the majority of cases of low-grade FMS occur in young to middle-aged adults, commonly in deep soft tissues of the shoulder region, the extremities and the trunk. Histologically, low-grade MFS shows a multinodular growth pattern and is composed of round or polygonal tumour cells mixed with elongated, curvilinear, thin-walled blood vessels in a myxoid matrix. The tumour cell nuclei in low-grade MFS display at least moderate nuclear pleomorphism and hyperchromasia. Low-grade FMS, however, is composed of bland fusiform tumour cells arranged in a whorled or swirling pattern, or occasionally more linear, and set characteristically in an alternating fibrous and myxoid stroma. Low-grade MFS recurs frequently but has a very low metastatic potential, whereas low-grade FMS is characterised by an indolent but ultimately malignant clinical course with metastases in more than half of the cases, which underlines the importance of distinguishing between the two entities.

Adult↗
PubMed1996

[CD34 detection--an immunohistochemical contribution to differential diagnosis of soft tissue tumors].

CD34 is a myeloid progenitor cel antigen and present in endothelial cells and almost all vascular lesions. Additionally, CD34 has been described in numerous fibroblast-like cells and different mesenchymal tumours. The immunohistochemical evidence of CD34, however, may be of importance in the differential diagnosis of benign and malignant soft tissue lesions, if clinicopathological features and other immunohistochemical markers are regarded properly. We studied the CD34 immunopositivity of solitary fibrous tumour at different sites (11 out of 11 tumours tested stained positive), dermatofibrosarcoma protuberans (15 out of 18 stained positive), and gastrointestinal stromal tumour (15 out of 15 stained positive), and discuss the significance of these results in differential diagnosis to morphologically comparable soft tissue lesions.

Adolescent↗
PubMed1996

[Infantile rhabdomyofibrosarcoma. An aggressive tumor in the spectrum of spindle cell tumors in childhood].

We report a case of an intrathoracic, extrapleural, infantile rhabdomyofibrosarcoma in a 4-year-old boy. Histologically, the primary lesion showed extensive hyalinization and stroma sclerosis and was composed of relatively uniform spindle-shaped, at least focally rather polygonal tumour cells with scattered intracytoplasmatic globoid inclusions. Although chemo- and radiotherapy was given postoperatively, local recurrences and metastases in the lung and thymus have developed; the patient died of tumour disease 3 years later. Recurrences and metastases showed features of tumour progression with higher cellularity and increased mitotic activity. Immunohistochemically, the tumour cells stained strongly positive for vimentin, desmin, and muscle-specific actin, and at least focally for MyoD1; the tumour did not stain for alpha-smooth muscle actin, neural and epithelial markers, or CD34 and CD31. The differential diagnosis of these aggressive tumours in the spectrum of spindle-cell lesions in early childhood is discussed.

Biomarkers, Tumor↗
PubMed1996

Photodynamic therapy on the normal rabbit larynx with phthalocyanine and 5-aminolaevulinic acid induced protoporphyrin IX photosensitisation.

Photodynamic therapy (PDT) is a promising technique for the treatment of small tumours in organs where it is essential to minimise damage to immediately adjacent normal tissue as PDT damage to many tissues heals by regeneration rather than scarring. As preservation of function is one of the main aims of treating laryngeal tumours, this project studied the effects of PDT on the normal rabbit larynx with two photosensitisers, endogenous protoporphyrin IX (PPIX) induced by the administration of 5-aminolaevulinic acid (ALA) and disulphonated aluminium phthalocyanine (AIS2Pc). The main aims of the study were to examine the distribution of protoporphyrin IX and AIS2Pc by fluorescence microscopy in the different regions of the larnyx and to assess the nature and subsequent healing of PDT damage. Peak levels of PPIX were found 0.5-4 h after administration of ALA (depending on dose) with highest levels in the epithelium of the mucosa. With 100 mg kg-1, PDT necrosis was limited to the mucosa, whereas with 200 mg kg-1 necrosis extended to the muscle. With 1 mg kg-1 AIS2Pc, 1 h after administration, the drug was mainly in the submucosa and muscle, whereas after 24 h, it was predominantly in the mucosa. PDT at 1 h caused deep necrosis whereas at 24 h it was limited to the mucosa. All mucosal necrosis healed by regeneration whereas deeper effects left some fibrosis. No damage to cartilage was seen in any of the animals studied. The results of this study have shown that both photosensitisers are suitable for treating mucosal lesions of the larynx, but that for both it is important to optimise the drug dose and time interval between drug and light to avoid unacceptable changes in normal areas.

Aminolevulinic Acid↗
PubMed1996

Myxofibrosarcoma. Clinicopathologic analysis of 75 cases with emphasis on the low-grade variant.

Myxofibrosarcoma is one of the most common sarcomas in the extremities of elderly patients. We analysed the clinicopathologic features in a series of 75 patients. All patients were adults (range, 22-91 years; median, 66 years) with an approximately equal incidence in men and women. Thirty-five tumors arose in the lower and 25 in the upper extremities, nine on the trunk, two each in the retroperitoneum and the head and neck region, and one each in the pelvis and penis. Forty-eight cases (69.5%) were located in dermal or subcutaneous tissues. Distinctive histologic features included the following: a commonly nodular growth pattern; a myxoid matrix containing elongated, curvilinear capillaries; and fusiform, round or stellate tumor cells with indistinct cell margins, slightly eosinophilic cytoplasm, and hyperchromatic atypical nuclei. These lesions varied from a hypocellular, mainly myxoid, and purely spindle-cell appearance (low-grade neoplasms) to high-grade, pleomorphic (malignant fibrous histiocytoma-like) lesions with multinucleated giant cells, high mitotic activity, and areas of necrosis. Immunohistochemistry in 44 cases revealed only vimentin and occasional actin positivity. Ultrastructurally, tumor cells had a fibroblastic phenotype. DNA flow cytometry and proliferation analysis showed an association between aneuploidy and histologic grade. An average follow-up of 45 months (range, 5-300 months) in 60 cases has revealed local recurrence in 33 cases (54%). Thirteen patients developed metastases, and 13 tumor-related deaths occurred. A short interval to first local recurrence was associated with poor clinical outcome. The rate of local recurrence was independent of histologic grade, but only intermediate and high-grade neoplasms metastasized. The depth of the primary lesion did not influence the incidence of local recurrence. However, in deep-seated neoplasms, the incidence of metastases was higher and the percentage of tumor-related deaths was twice as high as in superficially located lesions, reflecting the fact that deep-seated lesions tended to be higher-grade, larger tumors. Myxofibrosarcoma tends to become progressively higher grade in recurrences, as demonstrated in five cases in our series. The poorly recognized low-grade myxofibrosarcoma is emphasized, as proper diagnosis and treatment and scrupulous follow-up are mandatory to avoid local recurrence and gradual tumor progression to a higher-grade neoplasm that may then metastasize.

Adult↗
PubMed1995

Lipomatous tumours of soft tissues: an update.

This review summarizes the clinicopathological features of recently characterized variants of lipomatous tumours of soft tissue, attempts to deal with some difficult conceptual issues relating to adipocytic neoplasms and aims to provide an update on cytogenetic aspects of fatty tumours. Myolipoma is a rare benign neoplasm, occurring most frequently in adults in the deep soft tissue of the abdomen or retroperitoneum, and is composed of irregularly admixed mature adipose and smooth muscle tissues. Chondroid lipoma represents an unusual benign lesion occurring mainly in adult females subcutaneously or in deep soft tissue; it is easily mistaken for myxoid liposarcoma or extraskeletal myxoid chondrosarcoma. Spindle-cell liposarcoma is a variant of well-differentiated liposarcoma quite commonly found in subcutaneous tissue of the shoulder region and upper limbs and is composed of relatively bland-appearing spindle cells mixed with a well-differentiated liposarcomatous component. Recently there has been considerable debate about classification of lipomatous tumours. The term atypical lipoma was proposed for a group of well-differentiated non-metastasizing liposarcomas arising in surgically amenable soft tissues and for deep-seated atypical adipocytic neoplasms that show variation in adipocytic size and atypical stromal cells but lack lipoblasts. However, these neoplasms recur repeatedly and may dedifferentiate and thereby acquire metastatic potential. We use the diagnosis atypical lipoma with caution and propose to use the terms well-differentiated liposarcoma and atypical lipoma interchangeably. The relationship between myxoid and round-cell liposarcoma, which constitutes the morphological spectrum of a single entity, has been clarified but there remain considerable problems in defining likely clinical behaviour. The recent advances in cytogenetic characterization and classification of lipomatous tumours, which is already proving to be of diagnostic importance, are reviewed, and the genetic importance of the distinct chromosomal translocation in myxoid/round cell liposarcoma is briefly discussed.

Adult↗
PubMed1995

[Ectopic hamartomatous thymoma. Case report with special reference to differential diagnosis].

We report the case of an ectopic hamartomatous thymoma in a 56-year-old male patient. The lesion arose subcutaneously in the supraclavicular region. Histologically, the well-circumscribed but unencapsulated tumour was composed of uniform fusiform tumour cells. In addition, mature fatty tissue, scattered T-lymphocytes, and an epithelial and a myoepithelial tumour cell component were found. The epithelial differentiation of the spindle cell tumour component was confirmed immunohistochemically and by electron microscopy. Ectopic hamartomatous thymoma has to be distinguished from ectopic cervical thymoma, thymolipoma, ectopic salivary tissue, teratoma, peripheral nerve sheath tumours, malignant epithelial tumours with thymus-like differentiation, biphasic synovial sarcoma, and skin adnexal tumours.

Biomarkers, Tumor↗