PubMed Health⌕ Search

Biomedical subjects

C Schmoeckel

Publications and source records attributed to C Schmoeckel.

At least 19 recordsLinked to original sources
PubMed1992

Myoepithelial differentiation in benign sweat gland tumors. Demonstrated by a monoclonal antibody to alpha-smooth muscle actin.

One hundred and two cases of benign sweat gland tumors of the skin were studied for the presence of myoepithelial cells specifically identified by a monoclonal antibody to alpha-smooth muscle actin on paraffin-embedded tissues. The monoclonal antibody gave a positive result in 12 of 12 cases of cylindroma, 14 of 16 cases of spiradenoma, 2 of 2 cases of apocrine tubular adenoma (papillary eccrine adenoma), 5 of 5 cases of apocrine hidrocystoma, 5 of 5 cases of hidradenoma papilliferum, and in 10 of 10 cases of syringocystadenoma papilliferum. Rare myoepithelial cells were detected in only 1 of 10 cases of mixed tumor, apocrine type. There was no immunoreactivity for alpha-smooth muscle actin in eccrine hidrocystoma (2 cases), mixed tumor of eccrine type (2 cases), syringoma (7 cases), hidroacanthoma simplex (1 case), eccrine poroma (14 cases), clear cell hidradenoma (15 cases), and in 1 case of eccrine syringofibroadenoma. Our data support the concept that myoepithelial cells are seen in most sweat gland tumors considered to differentiate toward the secretory coil of the normal sweat gland. In contrast, myoepithelial cells are absent in tumors showing differentiation toward the excretory (ductal) component of the gland.

Actins↗
PubMed1992

[Lichen ruber hypertrophicus with verrucous carcinoma].

A 51-year-old patient presented with aggregated papules and with a central, partly erosive plaque on the left lower leg. Histological examination revealed hypertrophic lichen planus peripherally and a verrucous carcinoma within the centre. The lesion was removed surgically. Shortly after wards an atrophic lichen planus developed exclusively within the skin graft, which was effectively treated with topical steroid cream. The patient remained disease-free for 2 years. The literature relating to malignant transformation of cutaneous lichen planus was reviewed. In most cases, as in the present one, the hypertrophic form of lichen planus and the verrucous type of carcinoma (Ackerman) are reported. Recent investigations have revealed human papilloma virus types 6 and 11 within such lesions.

Carcinoma, Papillary↗
PubMed1991

Inflammatory cellular infiltrates in melanocytic nevi.

We examined 1,054 melanocytic nevi [137 (13%) simple lentigines, 158 (15%) junctional nevi, 337 (32%) compound nevi, and 422 (40%) dermal nevi] for the presence of lymphohistiocytic infiltrates. The following criteria were evaluated: age and sex of the patient, location, histological type, horizontal and vertical diameter, increase of melanocytes in the basal layer of the epidermis, increase of melanophages in the papillary dermis, melanin content of keratinocytes, and melanin content of nevus cells. Lymphohistiocytic infiltrates were measured semiquantitatively; their presence within the center, in the lateral margins, or both was also determined. The results were analyzed statistically by means of chi-square tests and univariate and multivariate analyses. We found that 824 lesions (78%) were associated with a lymphohistiocytic infiltrate; whereas 230 (22%) were not. This infiltrate was weak in 273 cases (33%), moderate in 411 cases (50%), pronounced in 130 cases (16%), and very strong in 10 cases (1%). Multivariate analyses revealed that the only criteria associated with the presence of lymphohistiocytic infiltrates were the increase of melanocytes in the basal layer and the vertical thickness in compound nevi. All other parameters were statistically insignificant. We conclude that melanocytic nevi with a junctional hyperplasia of melanocytes--i.e., mostly early stages such as simple lentigines, junctional nevi, and superficial compound nevi--are often associated with a moderate to pronounced cellular stromal reaction. Their presence may reflect the appearance of antigens on proliferating melanocytes. It may also represent a stromal reaction to necrotic tumor cells and keratinocytes within the dermoepidermal junction. These findings rule out any relationship to an increase of melanin pigment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Ultrastructural discrimination between malignant melanomas and benign nevocytic nevi using high-resolution image and multivariate analyses.

Prompted by the well-known difficulties of reliable and objective histologic differentiation between initial malignant melanoma (MM) and benign nevocytic nevi (NN), ultrastructural high-resolution image and multivariate analyses were evaluated for their diagnostic efficiency. Thirty-seven different features describing morphometry (area, circumference, and shape factor), amount of heterochromatin and euchromatin, chromatin homogeneity, and presence of smaller dark chromatin aggregations were determined by a MICROVAX 3500 computer in each of 1840 intraepidermal melanocytic nuclei of 17 MM and 20 NN. A strategy for the classification of cases based on the identification of markedly atypical melanocytic cells (MACS) was developed. MACS, selected in multivariate analysis with a linear combination of the eight most important features for cell classification, were found in 39.4% of the melanoma cells, but only in 0.3% of nevocytic nevus cells. The presence of MACS allowed a clear differentiation between MM and NN. All cases of MM had more than four MACS, whereas 17 cases of nevocytic nevi were MACS negative, and in each of the remaining three cases only one MAC was present. The percentage of MACS detected within intraepidermal parts of MM by using computerized high-resolution image analysis was found to be a highly efficient diagnostic marker. The new classification strategy has the potential of saving considerable time in subsequent studies, because preselected sampling and the calculation of only a few criteria have proven sufficient for correct classification of malignant melanomas.

Chromatin↗
PubMed1990

Identification of basement membrane components in eosinophilic globules in a case of Spitz's nevus.

A case of Spitz's nevus with eosinophilic globules was examined using antibodies for several components of the basement membrane. Aggregated tumor cells revealed the same characteristics as normal nevocytic nevi, that is, they were surrounded by laminin and type-IV collagen, whereas type-VII collagen was absent. All of these components of basement membranes, including type-VII collagen, were also found in eosinophilic globules, which were densely stained by these antibodies. It is assumed that these eosinophilic globules are essentially composed of basement membrane components, which are probably synthesized by epidermal and possibly also by melanocytic tumor cells.

Basement Membrane↗
PubMed1990

[Encapsulated neuroma of the skin. A clinical, histologic and immunohistologic study].

Encapsulated neuroma of the skin is a little known, though not especially rare, benign tumour of the peripheral nerve system. It is often wrongly diagnosed on the basis of both clinical and histological investigation. We have subjected 24 encapsulated neuromas to clinical, histological, and immunohistological study. Clinically, they presented as solitary, skin-coloured small nodules, usually located on the face in middle-aged adults. Histologically, encapsulated neuromas are well-circumscribed dermal tumours. They are composed of interlacing fascicles of Schwann cells (S-100 protein +) and numerous tiny axons (S-100 protein +, neurofilament +). Most reveal at least partial encapsulation with perineurial differentiation (EMA +, vimentin +). Encapsulated neuromas can be differentiated from other tumours of the peripheral nerve system and from leiomyoma by their distinctive histological and immunohistological features.

Adult↗
PubMed1989

Association of early malignant melanoma with nevocytic nevi.

The percentage of histologically associated malignant nevocytic nevi is essential for establishing concepts of histogenesis. The literature abounds with studies of this association. However, the results are conflicting and vary between 4% and 72% of malignant melanomas with associated nevocytic nevi with a maximum frequency between 20% and 30%. These different values could be partially explained by the fact that tumors in more advanced stages might have "overgrown" preexisting nevocytic cells. For this reason, only cases of early stage malignant melanoma (tumor thickness less than or equal to 1.5 mm; level of invasion less than or equal to III) were included in this study (n = 150). Thirty-three (22%) of 150 cases of malignant melanoma were associated with nevocytic nevi. In an additional 6.1% of the cases there was a possible but doubtful association. In 45.4% of the cases the nevus cells could be detected below the tumor, in 18.2% they could be seen at the laterally adjacent sides, and in 36.4% they were found at both sites. Fifty percent showed junctional activity from the nevocytic nevi located to the side of the melanoma. We conclude that the finding of approximately 27% of nevocytic nevi with junctional activity among the nevocytic nevi associated with malignant melanoma could be an indicator that at least some malignant melanomas develop within or next to a preexisting and still proliferating nevocytic nevus.

Humans↗
PubMed1989

Semiquantitative analysis of histologic criteria in thin malignant melanomas.

To evaluate the sensitivity of histologic criteria 396 hematoxylin-eosin-stained step sections of 150 randomly sampled thin malignant melanomas (tumor thickness, less than or equal to 1.5 mm; level of invasion, I-III) were analyzed. The highest sensitivity was determined for nuclear atypia (84%), followed by the asymmetry of the lesion (81.3%) and the presence of single cells in the upper layers of the epidermis (80.3%). The sensitivity was limited for the inflammatory reaction of the dermis (56%), poor demarcation of the lesion (49.3%), and infiltration of the adnexa (47.7%). For the mitotic activity a low sensitivity was found (33.3%). In only 7.6% of cases all criteria investigated (with the exception of the infiltration of adnexa) were simultaneously present. The three most sensitive criteria could be found in 46% of cases and two of these criteria in 88% of cases. In conclusion, this semiquantitative analysis of histologic criteria revealed that (1) thin malignant melanomas can be diagnosed with a few, but very sensitive, criteria and (2) the absence of criteria with minor sensitivity is not helpful for correct diagnosis.

Humans↗
PubMed1989

Structure of basement membranes in malignant melanoma and nevocytic nevi.

Basement membranes found around tumor cells in nevocytic nevi, Spitz's nevi, and malignant melanomas were analyzed by electron microscopy and antibody staining for several basement membrane proteins. Nevocytic nevi and Spitz's nevi showed a distinct, occasionally discontinuous lamina densa regardless of whether they were located in junctional zones of the epidermis or within the dermis. All basement membranes around nests of aggregated nevus cells, however, lacked anchoring fibrils. This correlated with the absence of type VII collagen. In contrast, type IV collagen, laminin, and nidogen were present at the periphery of the nevus cell clusters in agreement with the presence of an intact lamina densa. Aggregated tumor cells in malignant melanomas were bordered by a lamina densa when located in a junctional position and lacked this structure when they had migrated into the dermis. This process was accompanied by a drastically reduced staining for collagen type IV and nidogen, whereas laminin was still detectable. Anchoring fibrils and their molecular correlate, type VII collagen, were consistently absent. These observations demonstrate major alterations in the composition of basement membranes around malignant melanomas, which can be an important factor for the invasive growth and formation of metastases of these tumors.

Antibodies↗
PubMed1989

[Acquired hyalinosis cutis et mucosae in plasmacytoma with monoclonal IgG-lambda gammopathy].

A 66-year-old female patient developed within 2 years clinical symptoms of hyalinosis cutis et mucosae due to a plasmocytoma with monoclonal IgG-light-chain gammopathy. The clinical diagnosis was supported by light- and electron-microscope studies. The form of hyalinosis cutis et mucosae described by Urbach and Wiethe is a genetic disease with its onset in early childhood. For this reason, we propose the designation "acquired hyalinosis cutis et mucosae" for the case reported here.

Aged↗
PubMed1989

[Olmstedt syndrome--associated with primary sclerosing cholangitis and immune deficiency of uncertain origin].

The Olmstedt syndrome is an erythrokeratodermia of unknown aetiopathogenesis, which mostly becomes manifest in early childhood. Skin lesions involve palms, soles and the periorificial regions. Up to now only 6 cases have been reported. We present a new case of a 45-year-old woman who had started developing the characteristic skin lesions at the age of 30. Remarkably, primary sclerosing cholangitis and an immunodeficiency of an unknown origin were present in this patient. Systemic treatment with glucocorticosteroids cleared the periorificial lesions temporarily, whereas the palmoplantar keratoses hardly responded to therapy. An attempt at treatment with retinoids was precluded by the presence of hepatic disease.

Candidiasis, Vulvovaginal↗
PubMed1989

[The number and distribution of nevus cell nevi in patients with malignant melanoma].

Total-body cutaneous examination of 211 patients with malignant melanoma (MM) and 157 controls showed that patients with MM had significantly more nevi. Among MM patients, men had more nevi on the trunk than women, and women had more nevi on the lower extremities than men. Men had an MM distribution that was similar to their nevus distribution. Women, however, had proportionately more MM on the legs and fewer MM on the neck. The "nevus density," defined as the number of nevi per unit surface area of skin, was higher in male MM patients. The nevus density was highest on the head and neck, and lower on the lower extremities and anterior trunk. Patients with nodular melanoma had more nevi than those with superficial spreading melanoma. MM patients with a family history of many nevi had more nevi than those without such a history. Patients with a family history of MM did not show an increased number of nevi, but they had larger numbers of suggestive nevi removed than those without a family history of MM. We believe that many of these observations are consistent with the view that MM is caused by a genetic predisposition to an overactive melanocytic system in combination with an external stimulant, such as UV radiation.

Adolescent↗
PubMed1988

Congenital spiradenoma.

A case of an adenomatous sweat gland hamartoma present since birth is described. The histological and ultrastructural findings were similar to those of spiradenoma, and carcinoembryonic antigen, usually present in cutaneous sweat gland tumors, was also demonstrated. Sweat gland nevi are rare, and a spiradenomatous variant has not been previously documented.

Adenoma, Sweat Gland↗