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Biomedical subjects

B G Zelger

Publications and source records attributed to B G Zelger.

34 records · Page 2Linked to original sources
PubMed1997

Non-Hodgkin lymphoma with exclusive involvement of the heart and the gastrointestinal tract.

An extranodal high-grade B-cell lymphoma, centroblastic type, with exclusive involvement of the heart, stomach and small bowel was detected at post-mortem examination following the death of an 80-year-old man. Autopsy revealed massive cardiomegaly with a total heart weight of 1800 g owing to an intramyocardial tumour involving the right ventricle, and multiple mucosal tumour plaques and nodules in the stomach and small bowel. The case highlights the difficulties of diagnosing cardiac lymphoma clinically even in the presence of a large tumour mass.

Aged↗
PubMed1997

Ovarian Sertoli-Leydig cell tumor: a SRY gene-independent pathway of pseudomale gonadal differentiation.

Sertoli-Leydig cell tumors (SLCT) are rare sex-cord stromal tumors of the ovary composed of undifferentiated gonadal stromal cells, Leydig cells (LC), and Sertoli cells (SC), with the latter forming structures resembling fetal testicular tubules. The histogenetic basis of morphological male differentiation patterns in females is controversial. Here, we report a SLCT with intermediate differentiation in a 23-year-old woman investigated by light microscopy, immunohistochemistry for intermediate filaments, and sex steroid hormone receptors (SSHR), as well as by polymerase chain reaction (PCR) for the presence of the sex-determining region Y gene (SRY). Our investigation shows that the SCs of SLCT express progesterone and androgen receptors as well as cytokeratins and vimentin. By PCR, SLCT-derived genomic DNA lacked the SRY gene, indicating that the SLCT results from a SRY gene-independent pathway of pseudomale gonadal differentiation. The expression of progesterone receptors (PRs) in the SCs of the SLCT is in contrast to their absence in testicular SCs, but in line with their presence in ovarian granulosa and surface epithelial cells. Thus, our results provide strong evidence for a close histogenetic relationship between the SLCT and the female gonocyte-supporting cell, the granulosa cell (GC).

Adult↗
PubMed1997

Sclerotic lipoma: lipomas simulating sclerotic fibroma.

AIMS: We report a series of five unusual subcutaneous lipomas characterized by prominent stromal sclerosis in a storiform arrangement. METHODS AND RESULTS: All lesions occurred in young male adults (23.0 +/- 9.5 years), three lesions were on the scalp and two on the hands. Clinically, lipoma, chondroma or some form of cyst were suspected. In contrast to sclerotic fibroma ('circumscribed storiform collagenoma') a variable number of adipocytes were interspersed within the fibrosclerotic background. These cells also showed immunoreactivity for S100 protein as well as intracytoplasmic lipid deposits ultrastructurally. None of the lesions recurred within a follow-up period of between 0.5 and 9 years. CONCLUSIONS: Our series suggests that sclerotic lipomas should be classified with fibro- and myxolipomas, angiolipomas, spindle cell and pleomorphic lipomas, as an additional characteristic subtype of lipoma. Sclerotic lipomas are often misdiagnosed as a sclerotic fibroma, but are essentially fatty tumours and are, at least in our small series, not associated with Cowden's disease.

Adolescent↗
PubMed1997

Granular cell dermatofibroma.

AIMS: To describe a series of five granular cell dermatofibromas as an unusual and rare manifestation of fibrohistiocytic tissue response. METHODS AND RESULTS: Five granular cell dermatofibromas were collected out of 136 tumours filed as granular cell tumours. Clinically, all lesions occurred on the shoulder or back of middle-aged adults (two women, three men), mostly with the clinical diagnosis of a fibrohistiocytic lesion. Histology revealed well-circumscribed, dermal to subcutaneous lesions dominated by periodic acid-Schiff (PAS) positive, granular cells. Acanthosis above, as well as storiform arrangement of spindle cells, sclerotic collagen and some interspersed lymphohistiocytic infiltrate at the periphery of the lesion, indicated the fibrohistiocytic origin. Lesions showed prominent reactivity with NK1C3 (CD57), as well as for macrophage markers KiM1p and KP1 (CD68). In contrast to classic Schwannian/neurogenic granular cell tumours, granular cell dermatofibromas were S100 protein negative, but showed variable reactivity for factor XIIIa (10-50%) in 4/5, for smooth muscle specific actin (10-50%) in 2/5 and with E9 (10-30%) in 3/5 lesions. Electron microscopy in one case revealed large pools of phago-lysosomes and variably sized glycogen granules in granular cells. CONCLUSION: Our series delineates granular cell dermatofibroma as a distinct clinicopathological variant of fibrohistiocytic tissue response which needs to be distinguished from other tumours with granular cell features.

Adult↗
PubMed1997

Clear cell dermatofibroma.

This series presents six cases of a rare variant of dermatofibroma, characterized by marked clear cell change. All lesions occurred on the lower extremities of middle-aged adults (four women, two men), mostly with the clinical diagnosis of fibrohistiocytic lesion. Histological examination revealed well circumscribed, faintly stained dermal to subcutaneous lesions which were due to the overwhelming presence of clear cells (> 90%), some with prominent PAS-positive cytoplasmic granulation. Overlying epidermal hyperplasia as well as storiform arrangement of spindle cells, sclerotic collagen and some interspersed lympho-histiocytic infiltrate at the periphery of the lesion indicated the fibrohistiocytic origin. Individual histopathological peculiarities included: bizarre giant cells in two cases, perifollicular arrangement and haemangiopericytoma-like features with iron deposition in one case each. Immunohistochemically three of four lesions showed moderate reactivity for factor XIIIa and two of four with an anti-metallothionen marker E9, but were otherwise negative with a broad panel of markers. Electronmicroscopy in two cases revealed large pools of glycogen beside focal, prominent endoplasmic reticulum and lysosomes in some granular cells, but only optically translucent cells in cases of clear cells. Recognition of clear cell dermatofibroma is important as the differential diagnosis includes some entities with more serious outcome/considerations such as metastases of renal cell carcinoma, xanthogranulomatous reactions, balloon cell naevus/melanoma and clear cell sarcoma.

Adult↗
PubMed1997

Prominent myofibroblastic differentiation. A pitfall in the diagnosis of dermatofibroma.

Myofibroblastic differentiation occurs in 10-20% of all dermatofibromas, affecting < 25% of cells. We report on a series of 36 dermatofibromas collected from > 1,500 fibrohistiocytic lesions (2%), with more prominent (> 25%) myofibroblastic differentiation characterized by markedly slender and elongated spindle cells positive for smooth muscle markers. While most of the lesions did not otherwise differ from ordinary dermatofibromas, three cases (0.2%) from the neck-shoulder region of male adults showed extensive myofibroblastic features (> 90%). Clinically, these three lesions measured approximately 1 cm and had a firm consistency, with the differential diagnosis of some fibrohistiocytic tissue response. Histologically, densely packed cells and prominent, partially nodular, stromal sclerosis with focal palisading of nuclei indicate some overlap with other rare variants of fibrohistiocytic tissue response, such as cellular benign and palisading cutaneous fibrous histiocytoma. Yet, these features together with focal whorled nesting of more epithelioid cells (one case) also caused considerable diagnostic problems to exclude other myofibroblastic as well as (malignant) spindle cell lesions such as (palisaded) myofibroblastoma, dermatofibrosarcoma protuberans, and neurothekeoma. Immunohistochemically, all lesions were markedly (> 90%) labeled for smooth muscle markers (HHF35, anti-SMA) and with NK1C3 (CD57), while a broad panel for other spindle cell tumors, such as pan-keratin, S100 protein, EMA, desmin, CD34, CD31, and KiM1p, were negative. Electron microscopy of two cases revealed prominent endoplasmic reticulum and Golgi complex, numerous intermediate filaments, attachment plaques, and focal basal lamina formation. No recurrence was seen during a follow-up of 9 (two cases) and two years, respectively.

Actin Cytoskeleton↗
PubMed1997

Verocay body--prominent cutaneous schwannoma.

We report on eight cases of a distinct variant of cutaneous schwannoma characterized by prominent Verocay body formation (75-100% of the tumor bulk) that may cause considerable diagnostic difficulties. Like ordinary cutaneous schwannomas, these lesions preferred the head and neck region of young adults without sexual predilection and were clinically interpreted as cyst, basal cell carcinoma, or nevus. Histological examination revealed well-circumscribed nodules. Three of them consisted exclusively of nodular or ribbon-like Verocay bodies. A variable admixture of Antoni A or B type of differentiation (< 25%) was seen in five other cases. The following patterns were seen: fascicular spindle-shaped, onion-like epithelioid, myxoid-hypocellular, and degenerated ("ancient") with prominent fibrosis/hyalinosis and occasional bizarre giant cells. Immunohistochemically, the lesions were positive for S-100 protein (and vimentin) but negative for a broad panel of neurogenic and intermediate filament markers. The capsule showed focal labeling for EMA and--when it was markedly thickened--also for SMA. Labeling with E9, an anti-metallothionein marker indicative of cell activity, was negative, underscoring the slow growth potential of these lesions. No recurrence was seen in the six patients with follow-up information. The differential diagnosis includes other lesions with prominent palisading. (Amianthoid) myofibroblastoma and palisading leiomyoma are consistently positive for SMA and desmin, respectively. Palisading cutaneous fibrous histiocytoma and myofibroblastic dermatofibroma are variably positive for Factor XIIIa, SMA, and E9 and/or NK1C3 (CD57). Palisaded encapsulated neuromas are primarilly differentiated by the presence of nerve fibers with myelin sheaths.

Adolescent↗
PubMed1997

Dermal and subcutaneous variants of plexiform fibrohistiocytic tumor.

We report five cases of plexiform fibrohistiocytic tumors, three classic subcutaneous lesions and two dermal ones. Both variants had similar profiles and were clinically indistinguishable. The lesions affected the trunk more than the upper extremities and were found in children and young adults (18.4 +/- 12.8 years). They showed a marked female predominance (4:1, including both dermal variants). Clinically, they were skin-colored, hard nodules of 1-2-cm diameter that resulted in such differential diagnoses as fibroma, histiocytoma, pilomatricoma, or cyst. Interestingly, one subcutaneous case with a painful "worms in the sack" presentation was thought to represent a plexiform neurofibroma. Histology revealed well-circumscribed dermal or subcutaneous plexiform lesions with a characteristic biphasic appearance. Most of the tumor bulk consisted of spindle-shaped to stellate myofibroblasts with a variable admixture of collagen or loosening of stroma. In the center of the plexiform strands and nodules, a few osteoclast-like giant cells as well as epithelioid mononuclear cells (< 10%) were found. Myofibroblasts were positive with HHF35 and for smooth muscle actin in three of five cases. Osteoclast-like giant cells were positive with KP1 in all five cases. Both types of cells stained with the macrophage marker Ki-M1p. A broad panel of other markers was negative. This series expands the spectrum of plexiform fibrohistiocytic tumor, but it also broadens the differential diagnosis of (dermal) plexiform lesions, which at present includes spindle cell nevi, schwannomas, neurofibromas, granular cell tumors, nerve sheath myxomas (neurothekeomas), spindle cell lipomas, and tufted angiomas.

Adult↗
PubMed1997

Malignant melanomas simulating various types of soft tissue tumors.

BACKGROUND: Primary malignant melanomas, recurrences, and metastases thereof can present with a wide variety of clinicopathologic aspects. OBJECTIVE: The present series describes eight primary malignant melanomas and/or 10 local recurrences/metastases (from eight patients) misdiagnosed as various types of soft tissue tumors: two dermatofibrosarcoma protuberans, two atypical fibroxanthomas, two storiform-pleomorphic malignant fibrous histiocytomas, one myxofibrosarcoma ("myxoid malignant fibrous histiocytoma"), two malignant hemangiopericytomas, and nine malignant schwannomas. METHODS: In three cases correct diagnosis was established by clinicopathologic correlation during follow-up; all the others were only discovered during a retrospective work-up of all soft tissue tumors diagnosed at the Dermatohistopathological Laboratory of the Department of Dermatology, University of Innsbruck. RESULTS: Helpful clues derived from subtle intraepidermal, irregular spread of melanocytes, focal nested arrangement of tumor cells, sparse melanin deposition, neurotropism, and prominent peripheral lymphohistiocytic response, partially forming lymph follicles. Besides clinicopathologic correlation, histology of serial sections as well as immunohistochemistry (S100 protein more important than NK1/C3; HMB45 without benefit) and electron microscopy (melanosomes) proved helpful for definitive diagnosis. In contrast to the general assumption that spindle cell/desmoplastic malignant melanomas have an unequivocal bad prognosis, our series, as well as evidence from the literature, document a better prognosis than that of other types with comparable tumor thickness (70% vs 50% 5-year survival). Moreover, labeling with E9, an antimetallothionein marker, confirmed its usefulness for prognosis being strongly positive in primary lesions followed by rapid progression, but mostly negative in those without. CONCLUSION: These cases document that malignant melanoma may mimic various types of soft tissue tumors; correct interpretation is important as prognosis and therapeutic management differ considerably between these entities.

Aged↗
PubMed1997

Cutaneous epithelioid hemangioendothelioma, epithelioid cell histiocytoma and Spitz nevus. Three separate epithelioid tumors in one patient.

We report the unusual history of a young lady who, over a period of 9 years, developed 3 epithelioid neoplasms of different histiogenetic origin: a cutaneous epithelioid hemangioendothelioma, an epithelioid cell histiocytoma, and a Spitz nevus. To the best of our knowledge, such an unusual combination of neoplasms has not been reported previously and raises the question of an underlying "epithelioid" reaction pattern responsible for the epithelioid appearance in all 3 tumors; the likelihood of such a combination of tumors occurring in a single patient would be less than 1 in 1 billion.

Adult↗
PubMed1996

Aneurysmal and haemangiopericytoma-like fibrous histiocytoma.

AIM: To describe the clinicopathological features of 33 aneurysmal fibrous histiocytomas (AFH), including five cases with a haemangiopericytoma-like pattern. METHODS: Thirty three cases of AFH were studied by using routine histology and immunohistochemistry for factor XIIIa, the "cell activity marker" E9 (anti-metallothionein), NK1C3 (CD57), smooth muscle actin (SMA), factor VIII, ulex europaeus agglutinin, JC70A (CD31), and QBEND10 (CD34). The time dependent variation in histopathological features was evaluated by statistical methods (Pearson chi 2, likelihood ratio chi 2). RESULTS: Of the AFHs, 29 of 33 occurred on the extremities of adults (age range 30 to 50 years), six of which were associated with rapid growth, probably caused by trauma, and pain. Twenty one lesions were thought to be vascular and/or melanocytic lesions, including two melanomas, because of a bluish-black and/or cystic appearance. Histologically, large areas of haemorrhage, up to 50% of the tumour bulk, lacking an endothelial lining were seen in otherwise typical fibrous histiocytomas. Five cases resembled nodular stages of Kaposi's sarcoma. Variable haemosiderin deposition in histiocytes (18/33) and giant cells (11/33) was suggestive of haemosiderotic histiocytoma. A haemangiopericytoma-like pattern was seen in five otherwise indistinguishable cases. On immunohistochemistry, variable reactivity was seen for factor XIIIa (18/30), with E9 (18/30), NK1C3 (19/30), and for SMA (14/30), but labelling for vascular markers was not detected. Early lesions without iron deposition were factor XIIIa positive; late lesions with iron deposition were factor XIIIa negative. Labelling for SMA correlated with prominent sclerosis. CONCLUSION: AFHs, including a haemangiopericytoma-like variant, have a characteristic time dependent histological and immunophenotypic profile, clearly different from nodular type Kaposi's sarcoma.

Adult↗
PubMed1995

Monophasic cellular variant of infantile myofibromatosis. An unusual histopathologic pattern in two siblings.

Infantile myofibromatosis (IMF) is a distinct clinicopathologic entity characterized by solitary or multicentric tumors present at birth or in early infancy with a typical biphasic (central hemangiopericytoma-like, peripheral leiomyoma-like) histologic pattern. We present a case of IMF in two siblings with onset of disease in late childhood. Histology of the primary as well as several later tumors was characterized by a monophasic cellular appearance with a prominence of tiny capillaries initially suggesting an unusual vascular tumor. Diagnosis was established by the development of more characteristic biphasic lesions during the course of disease. Immunocytochemistry (Ulex, factor VIII, JC/70A [CD31], PAL-E, BMA120, EN4, QBEnd10 [CD34], SMS actin) and ultrastructural studies showed no (marked) differences between different types of IMF. The monophasic cellular pattern should be recognized as an unusual histologic manifestation of IMF, in particular in patients outside the classical setting or presentation.

Actins↗
PubMed1995

Solitary giant xanthogranuloma and benign cephalic histiocytosis--variants of juvenile xanthogranuloma.

Sequential biopsies taken from a patient with a solitary giant xanthogranuloma, an exaggerated macronodular (> 5 cm in diameter) variant of juvenile xanthogranuloma, and from a patient with benign cephalic histiocytosis, revealed a characteristic time sequence of histopathological findings. Early stages of the diseases showed a monomorphous infiltrate of mononuclear vacuolated histiocytes positive for KiM1p, HAM56 and factor XIIIa and were characterized by clusters of comma-shaped bodies. This was followed by a polymorphous mixture of various mononuclear and multinucleate histiocytes additionally labelling with KP1 (CD68) and, in occasional cells, for the adherence of peanut agglutinin. A variety of ultrastructural changes were found, including dense and regularly laminated bodies or lipid droplets. Our findings indicate that both entities are variants of a xanthogranulomatous reaction.

Antibodies↗
PubMed1995

Atrophic variants of dermatofibroma and dermatofibrosarcoma protuberans.

Dermal atrophy of more than 50% of the locoregional dermis may be the predominant histopathological feature in dermatofibroma and dermatofibrosarcoma protuberans. This may cause diagnostic difficulties. In the present study 26 cases of atrophic dermatofibroma were compared with three cases of atrophic dermatofibrosarcoma protuberans. Clinically, both conditions mostly occurred on the (upper) trunk of females. While atrophic dermatofibroma usually presented as a reddish, umbilicated lesion (0.5-1cm), often suspected to be a basal cell carcinoma, atrophic dermatofibrosarcoma protuberans showed irregularly arranged tan-brown plaques (3-6 cm). Histologically, atrophic dermatofibroma showed a regular silhouette with a smooth nodular (9/26) or scalloped lower margin with an intervening lace-like pattern of superficial fatty tissue infiltration (17/26) and variable sclerosis: atrophic dermatofibrosarcoma protuberans showed a deep, irregular infiltration of fatty tissue in a lacelike/honeycomb and/ or multilayered pattern, but no sclerosis. Immunohistochemically, atrophic dermatofibroma was mostly negative with QBEnd 10 (CD34;24/26), variably positive for factor XIIIa (20/26) and metallothionein (11/26). Labelling for factor XIIIa and metallothionein was usually seen in 'early' (metabolically active) lesions, while 'late' sclerotic ones were negative. In contrast to atrophic dermatofibroma all three atrophic dermatofibrosarcoma protuberans showed a consistently uniform profile: CD34 positive, factor XIIIa and metallothionein negative. Our study delineates atrophic dermatofibroma and atrophic dermatofibrosarcoma protuberans as distinct entities clearly distinguishable from each other by clinicopathologic criteria.

Adult↗
PubMed1995

Dermal spindle cell lipoma: plexiform and nodular variants.

We report on eleven cases of a distinctive dermal spindle cell lipoma characterized by a mixture of mature adipocytes and spindle-shaped cells in a fibromucinous background. Six lesions showed a moderately well circumscribed plexiform pattern, five a well demarcated nodular pattern with compression of surrounding connective tissue and prominent stromal fibrosis. Clinically, the plexiform type mostly occurred in the thigh-groin-buttock area and the nodular type in the head-neck or acral location. While plexiform lesions were predominantly seen in middle-aged females, nodular types occurred in young adults of either sex. No recurrence was seen in five patients with follow-up. The tumour cells were vimentin positive and a thin cytomplasmic rim of S-100 protein positivity was seen in mature adipocytes. Ultrastructural studies revealed lipoblastic differentiation of spindle-shaped cells with lipid droplets and basal lamina formation. Dermal spindle cell lipomas seem to be the dermal counterpart of the most subcutaneously located spindle cell lipoma.

Adipocytes↗