摘要:

Plasmacytoid monocytes (PCMs) are mononuclear cells of monocyte/macrophage origin with peculiar plasmacytoid features on electron microscopy. This cell type is largely unknown in dermatopathology, probably due to standard fixation procedures. The authors provide a detailed histopathologic, immunohistochemical, and electron-microscopic study of PCMs in Jessner's lymphocytic infiltration of the skin (LIS). PCMs occurred in 58% of all biopsy specimens from 75 patients with LIS in single or multiple clusters within the dermal infiltrates. Recognition of this cell type was important for differential diagnostic reasons because PCMs did not occur in polymorphic light eruption. In discoid lupus erythematosus. PCMs were present in only 7.3% of 110 biopsy specimens. PCMs are probably involved in the activation, proliferation, and differentiation of T-lymphocytes. Their origin and function are discussed and a special role in the homing of lymphocytes into the skin is suggested.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Using a silver staining technique, we studied nucleolar organizer regions (AgNOR) in paraffin sections of junctional nevi, compound nevi, intradermal nevi, blue nevi, dysplastic nevi, Spitz nevi, lentigo maligna, malignant melanomas in nevus, superficial spreading melanomas, and nodular melanomas. Two methods of counting black dots within nuclei were employed. One method was to count the discrete black dots within the nuclei, including the tiny black dots seen within the nucleolus; the second method did not take into account the subsidary cluster of tiny black dots seen within the nucleolus, instead treating these dots as a single structure. Whichever method we used, a significant difference was found between the pooled mean AgNOR numbers for benign and malignant lesions. We found an overlap, however, between benign, in particular Spitz and dysplastic nevi, and malignant lesions when considering individual counts of AgNOR using both methods. We conclude that studying AgNOR does not seem to be a useful technique to differentiate Spitz and dysplastic nevi from malignant melanomas.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

We compared 19 patients with acrodermatitis chronica atrophicans (ACA), a dermatosis caused byBorrelia burgdorferiinfection, and 40 patients with morphea, a disease of heterogeneous origin where a borrelia etiology has been suggested in some cases, both clinically and histologically to define the differences between these two dermatoses. Clinically, ACA involves acral body sites with lower temperatures, is seen mostly in elderly persons, and presents as a livid discoloration that is not sharply demarcated. Morphea can be localized in embryonal structures, affects any age and body site, and exhibits extension at the periphery of the lesions. Histologically, ACA shows atrophy of collagen and elastic tissue as well as hypertrophic basophilic elastic tissue; whereas in morphea, sclerosis and polarizing elastic tissue are prominent. Graft-versus-host-like reactions may be present in both dermatoses. Immunohistochemical testing with different lymphocyte markers showed differences only in the expression of HLA-DR antigens. These conditions can be distinguished from each other on a clinical and histological basis in most cases. In 17% of morphea biopsy specimens, however, histological differentiation from ACA was not possible. Moreover, the histological pattern of morphea was not associated with a positive borrelia serology.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

We studied a large panel of monoclonal antibodies reactive on routinely processed paraffin-embedded tissue to determine their sensitivity and specificity in the diagnosis of 35 primary cutaneous large cell lymphomas of B- (n = 14) and T-cell origin (n = 21). The findings show that differentiation between clinically relevant subgroups can be obtained by a small panel of antibodies including L26. MB2, LNI, MTI, UCHLI, and Ber-H2. Pitfalls in the use of the reagents are discussed.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Five cases of basal cell carcinomas (BCC) of the skin are described showing morphologic and immunohistochemical features of myoepithelial differentiation. Histologically, they were characterized by a dermal proliferation of tumor cells connected with the epidermis by areas showing the features of conventional BCC, with the deeper portions of the lesion showing a population of oval to spindle cells with eccentric nuclei and homogeneous, ground-glass, or hyaline eosinophilic cytoplasm characteristic of the so-called hyaline cell of myoepithelial tumors of salivary glands. Additionally, scattered cells showing a signet ring configuration were present, and in two cases, focal areas displaying chondromyxoid elements were also seen that appeared to merge imperceptibly with the surrounding spindle cell population. By immunohistochemistry, the tumor cells in the spindle cell component showed strong, diffuse positivity for CAM 5.2 and muscle specific actin, and variable expression of keratin AE1/AE3, vimentin, glial fibrillary acidic protein, and S-100 protein, these findings being consistent with the immunostaining pattern of myoepithelial cells and their neoplasms. A brief review of the literature on the topic is presented, along with a discussion of the possible pathogenesis of this process.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Among 30 patients who received a clinical diagnosis of exfoliative dermatitis and were hiopsied between 1982 and 1990, nine showed microscopic features of lichenoid dermatitis. Clinical information was available in eight of these cases. Possible etiologic factors included lymphoma, herpes simplex infection, connective tissue disease, and (in five cases) reactions to drugs. In each instance, microscopic features included a superficial perivascular lymphocytic infiltrate involving the dermal-epidermal interface, vacuolar alteration of the basilar layer, and individually necrotic keratinocytes at all levels of the epidermis. Such microscopic changes are not usually described in connection with exfoliative dermatitis, with the possible exception of those cases related to lichen planus or lupus erythematosus. Disseminated lichenoid drug eruption is one possible interpretation of the drug-induced cases. Erythema multiforme is another condition that has similar microscopic features and has been associated with drugs (many of which also cause exfoliative dermatitis), infectious agents, neoplasms, and connective tissue diseases. Lichenoid dermatitis can become generalized and clinically mimic an exfoliative dermatitis. Many, but not all, of these eruptions may be triggered by drugs.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

By using antibodies to type I, III, IV, V, and VI collagens and laminin, we examined the localization of interstitial collagens and basement membrane components with indirect immunofluorescence and immunoelectron microscopy (IEM). Furthermore, the morphological changes of these collagens in malignant transformation were investigated. In neurofibroma. IEM showed type I, III, and V collagens to be present diffusely on cross-striated collagen fibrils, whereas type VI collagen was present between the fibrils. Type IV collagen and laminin were observed to surround tumor cells. In neurofibrosarcoma, tumor collagen bundles that reacted with antibodies to type I, III, V, and VI collagens were irregularly arranged. Immunofluorescent deposits that reacted with anti-type IV collagen and anti-laminin antibodies were decreased in number, showing a thin and sparse arrangement.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Biopsy specimens of five connective tissue nevi were examined under crossed polars after staining with Picrosirius red. One biopsy specimen was from a solitary nevus, another from a Shagreen patch. The other three specimens were of erupted nevi. In all cases, thick (as well as thin) collagen fibers appeared green to yellow. In contrast, thick fibers of normal human dermis appeared orange to red. The findings indicate that the collagen of collagenous connective tissue nevi is less well packed than normal collagen. Examination of the polarization colors of Picrosirius red-stained sections is a useful procedure for diagnosing collagenous connective tissue nevi.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

We examined 512 malignant melanomas, representing all newly diagnosed cutaneous malignant melanomas, excluding lentigo maligna melanomas, from the period October 1, 1982 to March 31, 1985 occurring in the region of eastern Denmark in patients aged 20–79 years for the presence of dysplastic nevus remnants. Criteria for the diagnosis of a dysplastic nevus remnant include all the following changes (a) lentiginous or epithelioid melano-cyte hyperplasia. (b) cytologic melanocyte atypia. (c) eosinophilic fibroplasia, (d) lamellar fibroplasia, and (e) lymphocytic infiltration in the dermis. Dysplastic nevus remnants were found in association with 34 (7%) of the evaluable 512 malignant melanomas. Fourteen (41%) of the remnants were of compound nevus type. In nine (27%) of the remnants, atypia was pronounced. Most (62%) dysplastic nevus remnants were contiguous to thin superficial spreading melanomas. We conclude from this population-based study that about 7% of malignant melanomas arise in prior dysplastic nevi.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

This article reviews the lesions of oral mucosa that contain human papillomavirus (HPV). These HPV-associated lesions can be classified into two broad types on the basis of their biologic behavior, benign lesions and premalignant or malignant lesions. Benign oral lesions include squamous cell papilloma (SCP), verruca vulgaris (VV), condyloma acuminatum (CA), and focal epithelial hyperplasia (FEH). Of these entities. VV, CA, and FEH demonstrate characteristic HPV-induced cytopathic effects, whereas SCP infrequently shows such changes. All of these lesions show a clear association with HPV. Pre-malignant and malignant oral lesions include leukoplakia and squamous cell carcinoma. The etiologic role of HPV in these lesions is still unclear. Koilocytosis is the most common cytopathic effect seen in both groups of lesions. Even though it is sometimes difficult to distinguish between hyperplastic lesions such as SCP, VV, and CA, clinical and certain histologic features can facilitate the diagnosis. Although exceptions do exist, each of the two classes of lesions is most commonly associated with particular HPV types. The benign oral lesions are associated with HPV 2, 4, 6, 11, 13, and 32; the malignant oral lesions are associated with HPV 16 and 18. No preferential association has been demonstrated between specific HPV types and a particular oral lesion.

ISSN:0193-1091    

出版商:OVID    

年代:1991

数据来源: OVID