Biomedical subjects
M L Geerts
Publications and source records attributed to M L Geerts.
Kaposi's sarcoma in an AIDS patient.
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Prognostic significance of CD30 (Ki-1/Ber-H2) expression in primary cutaneous large-cell lymphomas of T-cell origin. A clinicopathologic and immunohistochemical study in 20 patients.
The histologic and immunophenotypical features of 20 primary cutaneous large-cell lymphomas of T-cell origin were investigated and correlated with clinical data to obtain prognostically relevant criteria. Histologic evaluation, using the updated Kiel classification, showed that these large-cell lymphomas represent a morphologic spectrum, often making classification rather arbitrary. It is therefore concluded that the clinical relevance of histologic subtyping is limited for this group of lymphomas. Immunophenotypical studies revealed significant differences between CD30-positive and CD30-negative lymphomas. CD30-positive lymphomas generally presented with localized skin disease, and had a favorable prognosis (9 of 10 patients alive and in complete remission; median survival, 37 months). In contrast, CD30-negative lymphomas often presented with or rapidly developed generalized disease; all patients died of lymphoma (median survival, 17 months). These findings suggest that CD30 expression is an important prognostic parameter for this group of primary cutaneous large-cell lymphomas.
[Cutaneous burns caused by Yperite. Apropos of 2 new cases].
Based on two of their own cases, the authors review the lesions produced by Yperite. This chemical agent produces cutaneous burns which are quite characteristic; histological study of biopsies carried out on cutaneous lesions was used to define the effects on the epidermis and dermis. The treatment of patients, with this rare condition, remains symptomatic.
Multiple clear cell acanthomas. A clinical, histological, and ultrastructural report.
A case of multiple clear cell acanthomas in a 64-year-old woman is reported. The clinical and histological findings of this rare entity are consistent with the hypothesis that clear cell acanthomas are benign epidermal tumors. An ultrastructural study was performed with special emphasis on the melanocytic-keratinocytic interaction.
[Congenital diffuse melanosis].
Two cases of diffuse congenital melanosis are presented. The hyperpigmentation appeared shortly after birth and invades progressively the trunk and the limbs. It is diffuse and most intensive on the abdomen and the back, and reticulated on the neck, the genitals and in the groins. The nails are thin and their surface is slightly irregular. Histologic examination reveals the presence of melanin in the deep and superficial layers of the epidermis. On electron microscopy the melanosomes are not grouped within the keratinocytes, but are dispersed throughout the cytoplasm of the epidermal cells. The disease can be considered as an autonomous entity. The mechanism of the hyperpigmentation is not known.
Tumour of Wagner-Meissner touch corpuscles. Wagner-Meissner neurilemmoma.
Two benign tumours composed mainly or exclusively of Wagner-Meissner corpuscles are described. In the first case the touch corpuscles are composed of closely piled laminar cells and surrounded by argyrophilic fibres. In the second case some Schwann cells are observed in between the tactile corpuscles. The light microscopic, electron-microscopic and immunohistochemical results demonstrate that these corpuscles are comparable with the tactile end organs of the skin. Immunohistochemically, neuron-specific enolase, vimentin and protein S-100 could be demonstrated in the tactile corpuscles. Neural processes present in normal Meissner corpuscles are absent and immunohistochemically no nerve fibres or nerve endings can be demonstrated using antibodies to neurofilaments as they are observed in normal touch corpuscles of the skin. Tumours which consist mainly of multiple touch corpuscles have not been described in the literature. It is suggested to call these tumours Wagner-Meissner neurilemmoma.
[Skin damage caused by the effect of nitrogen mustard gas].
The skin lesions seen in patients exposed to toxic war gases (dichlorethyl sulfide) are described. Histologic and electron microscopic findings are presented. The clinical course of the lesions is discussed.
A morphologic study of lymphadenosis benigna cutis.
Two skin biopsies of lymphadenosis benigna cutis have been analyzed by morphological and immunological methods using monoclonal and polyclonal antibodies on cryostat and paraffin sections. Follicular structures containing active germinal centers are composed of identical cell types as germinal centers of normal lymphatic tissue, e.g. centrocytes, centroblasts, immature plasma cells, dendritic reticulum cells and some T lymphocytes. Outside and inbetween the secondary follicles the infiltrate is composed of small T lymphocytes (OKT-3+, focal positive acid phosphatase reaction). Among T lymphocytes the OKT-4+ to OKT-8+ ratio was 2:1. Within these areas, consisting almost exclusively of T lymphocytes, cells with electron microscopical features of indeterminate cells and interdigitating reticulum cells were recognized. Those cells are OKT-6+. It can be concluded that in lymphadenosis benigna cutis the infiltrate of the dermis is composed of B and T cell areas which show the same microarchitecture and morphology as in normal lymphatic tissue.
Mycosis fungoides and lymphoplasmacytoid immunocytoma in the same patient. A case report.
The simultaneous occurrence of two different lymphomas in a 57-year-old white woman is reported: mycosis fungoides and a leukemic lymphoplasmacytoid immunocytoma. The first was confirmed by histologic study and electron microscopy, and the latter by histologic study and immunoperoxidase staining. The lymphoid cells in the involved bone marrow and peripheral blood expressed the same surface immunoglobulin as was found in the cytoplasm of the immunocytoma cells, i.e., IgM-lambda. The clonal B-cell expansion was brought into a lasting remission by chlorambucil, but the cutaneous lymphoma proved to be refractory to therapy. The patient died 38 months after diagnosis.
Alkaline phosphatase activity in non-Hodgkin's lymphomas and pseudolymphomas of the skin.
Alkaline phosphatase enzyme activity was studied histochemically in 60 non-Hodgkin lymphomas and 10 pseudolymphomas of the skin. Among the 37 B-cell lymphomas, membrane-bound alkaline phosphatase activity was demonstrated in 8 cases. In none of the 23 cutaneous T-cell lymphomas studied could membrane-bound alkaline phosphatase be detected. Among the pseudolymphomas, 2 cases revealed alkaline phosphatase activity. It was not possible to draw any particular clinically significant conclusions from the membrane-bound alkaline phosphatase reactions. Looking for the microenvironmental conditions of lymphoproliferative processes in the skin, alkaline phosphatase-positive capillaries were seen predominantly in the T-cell lymphomas. The stromal reaction showing a proliferation of alkaline phosphatase-positive fibroblasts was more pronounced in cutaneous B-cell lymphomas. In conclusion, membrane-bound alkaline phosphatase in lymphoproliferative processes in the skin, as in the lymph node, characterize a distinct group of B lymphocytes related to follicle center cells. The clinical relevance of this finding remains to be determined.
Alkaline phosphatase positive lymphoma.
Alkaline phosphatase (AP) activity on cryostat sections of the skin of 38 cases of non-Hodgkin's lymphomas of the B cell type and of 10 cases of lymphadenosis benigna cutis have been studied. Membrane-bound AP activity has been found in 8 out of 28 cases of low-grade malignant lymphomas of the B cell type and in 2 out of 10 cases of lymphadenosis benigna cutis. This is a known phenomenon in the latter. In the literature of non-Hodgkin's lymphoma AP activity is related to the intermediate type of lymphocytic lymphoma. Further studies are needed to demonstrate that the AP activity correlates with a specific cell type in the B lymphoid cell differentiation.
Morphological changes in the proximal area of the rat's hair follicle during early catagen. An electron-microscopic study.
This electron-microscopic study of the catagen phase shows that the first alteration of regression of the follicle is localized in the papilla, where the cells withdraw their offshoots and break the contact with the basal lamina. Both at the level of the papilla and of the bulb structures appear that increase the cell cohesion. Under the influence of the outer root sheath an upward migration occurs. This is followed by plication and thickening of the basal lamina. The alterations in the connective tissue sheath occur in a further stage. The first signs of autolysis occur in the center of the epithelial column. At the end of the catagen stage macrophages take care of the clearing-up.
Microenvironment of Woringer-Kolopp's disease.
A localized form of 'Pagetoid reticulosis' (Woringer-Kolopp's disease) is described morphologically. It can be shown that ultrastructurally the 'Pagetoid cells' are heterogenic and that different cell types can be distinguished: there are lymphoid cells, which often look like Lutzner cells, and nonlymphoid cells which can be characterized as indeterminate cells or Langerhans' cells. Often a close topographical relation between lymphoid and nonlymphoid cells can be demonstrated. This finding is suggestive for a functional interaction between the lymphoid cells, which are most probably T cells, and indeterminate cells and Langerhans' cells, which are known to be important for the thymus-dependent immune reaction. The presence of the nonlymphoid cell population in the epidermis in Woringer-Kolopp's disease seems to build up the specific microenvironment for lymphoid cell reaction.
[Tumors of the soles and palms].
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[Lyell's disease (author's transl)].
In Lyell's disease different clinical patterns can be observed: (a) an acute scarlatiniform erythema, on which more or less extended bullae rapidly appear; (b) a morbilliform erythema, with bullae; (c) the dermatosis can start under the features of an erythema exsudativum multiforme; (d) the eruption may begin as a psoriasis pustulosa. From an internal point of view, disturbances of the liquid balance and the blood electrolyte level may appear as a consequence of the important loss of water and serum. Toxic hepatitis, nephritis or myocarditis are possible complications. The origin of the disease is toxic or bacterial. This differentiation is important because the prognosis is much more favorable when the origin is bacterial than when the disease is due to medicines. A differential diagnosis between both etiologies may be achieved by histological examination: when the origin is a toxic one, we can find subepidermal blisters, while the blisters are located under the horny layer when the disease is of bacterial origin. The disease process is not clear in the toxic form. In cases induced by staphylococci, the epidermal lesions are caused by an epidermolytic toxin. The treatment will especially tend to restore the fluid and electrolyte balance; if there is a bacterial etiology, antibiotics will be necessary. Corticoids are to be avoided.