Anetodermic prurigo nodularis (with Pautrier's neuroma) responsive to arotinoid acid.

A woman had symmetrically distributed pruritic nodules for more than 40 years. Microscopically they were characterized by proliferation of nonmyelinated nerve fibers (Pautrier's neuroma) and a total absence of epidermal involvement. Anetoderma developed at the site of former nodules. Her condition responded favorably to repeated retinoid therapy with regression of nodules in those sites in which retinoid dermatitis had developed.

Relationship between Merkel cells and nerve endings during embryogenesis in the mouse epidermis.

Close relationships between Merkel cells (MC) and nerve endings (NE) exist in the adult mouse. Because MC may serve as targets for the ingrowth of NE during embryogenesis, the purpose of the present study was to analyze the relationship between MC and NE during embryogenesis. Frozen tissue from whisker pads and backs of NMRI mouse embryos (12-17 d gestational age) were studied by double-labeling indirect immunofluorescence (IIF) with a cytokeratin monoclonal antibody that recognizes MC and with a neurofilament anti-serum. Such an approach allowed the analysis of a large number of MC (up to 5000), thus yielding quantitative data. At day 12 of gestational age, no MC were observed by IIF. From day 13 to 17, the number of MC, as well as their association with NE, progressively increased. On day 13, only 57% of whisker pad MC were NE associated, whereas by day 17, 95% were NE associated. These results were confirmed by electron microscopic (EM) observations. On the back, the same chronologic relationship between MC and NE was observed, but was later in the course of embryogenesis. There was also a time- and zone-dependent increase in MC association with NE in the epidermal zones studied (isthmic, parafollicular, interfollicular). These observations 1) establish the time course of MC and NE contacts during embryogenesis in the mouse epidermis, 2) show that MC are present in the epidermis and appendages before NE reach the epithelium, and 3) support the hypothesis that MC could act as targets for the growing NE.

Cutaneous malignant melanomas occurring under cyclosporin A therapy: a report of two cases.

Two patients are reported with cutaneous malignant melanoma who had been on treatment with cyclosporin A. The first case was a 44-year-old man with systemic sclerosis and the second a 52-year-old woman who had a renal transplant. In both cases cyclosporin A was administered with a low dose of prednisone.

Juvenile chronic granulocytic leukemia, juvenile xanthogranulomas, and neurofibromatosis. Case report and review of the literature.

A 22-month-old boy had xanthomatous skin lesions, neurofibromatosis, and chronic granulocytic leukemia. Histologic examination of the xanthomatous skin lesions disclosed juvenile xanthogranulomas. Twenty-three previously published cases of this association are reviewed.

Nucleolar organizer regions in fibrohistiocytic tumors of the skin.

Nucleolar organizer regions (NORs) are loops of DNA which are present within the nucleoli of cells that possess ribosomal RNA (rRNA) genes. NORs are associated with proteins which can be visualized by a simple silver staining technique. As the number of NORs appears to reflect cell and nuclear activity its determination in benign, intermediate and malignant conditions could be of help in their differential diagnosis. In this study, we investigated 35 fibrohistiocytic tumors of the skin of benign, intermediate and malignant potential from 32 patients: 15 fibrous histiocytomas (FH), 5 FH with atypia (AFH), 7 atypical fibroxanthomas (AFX), 5 dermatofibrosarcoma protuberans (DFSP) and 3 malignant FH (MFH). A one-step silver technique was used on formalin or Bouin fixed specimens. Ag-NOR counts from benign conditions (FH, AFH) significantly differed from that of their intermediate-risk (AFX, DFSP) and malignant (MFH) counterparts. Furthermore, in 2 cases (one AFX; one MFH) which twice recurred, Ag-NOR counts steadily increased with time. However, a distinction could not be achieved between AFX and MFH. Although Ag-NOR is a simple and valuable technique, it does not allow a definite distinction between malignant and intermediate processes, at least as far as fibrohistiocytic tumors of the skin are concerned.

Tufted angioma.

The clinical and histological description of 2 cases of tufted angioma is presented.

Localization and characterization of the interleukin 1 immunoreactive pool (IL-1 alpha and beta forms) in normal human epidermis.

A panel of polyclonal antisera and monoclonal antibodies (MoAb) raised against recombinant human interleukin 1 alpha (rh IL-1 alpha) and beta (rh IL-1 beta) was used to localize IL-1 pools within epidermal compartments and to characterize the immunoreactive species. Interleukin 1 alpha and beta immunoreactive species were detected by Western blot analysis only when epidermal extracts were obtained in extraction buffers containing dithiothreitol (DTT), sodium dodecyl sulfate (SDS), or 2 mercaptoethanol. Together with the 31-kD (intracellular precursor molecule) and the 17-kD (mature, secreted form) species, most of the antisera and MoAb reacted with a protein of 52-kD that was not found in several internal organs, and from which a 31-kD form could be released upon reelectrophoresis. Interleukin 1 beta immunoreactivity was consistently found by immunohistology at the level of the stratum granulosum, where IL-1 alpha immunoreactivity, although less consistently, also localized. Several monoclonal antibodies to IL-1 beta reacted intensively and specifically with epidermal basal cells. At the electron microscopical level, IL-1 beta immunoreactivity was detected in the upper layers of the stratum granulosum; it appeared to be membrane associated and suggested an exocytosis process similar to that involving lamellar bodies. These observations 1) confirm the presence of IL-1 species in the normal unstimulated human epidermis, 2) show that both IL-1 alpha and beta are detectable herein, 3) identify 52-kD IL-1 alpha and beta immunoreactive bands that appear special to the epidermis, and 4) suggest a link between epidermal IL-1 and the differentiation process of the keratinocyte.

Spitz nevus (large spindle cell and/or epithelioid cell nevus). Age-related involvement of the suprabasal epidermis.

The Spitz nevus (large spindle and/or epithelioid cell nevus) is a benign acquired melanocytic tumour found predominantly in children and adolescents. Depending on the architecture (junctional, compound, dermal) and cytology (predominance of spindle or epithelioid cells, or presence of both cell types) several variants have been distinguished. A histological feature occasionally leading to diagnostic difficulties is the involvement of the suprabasal epidermis. The present study details the occurrence of intraepidermal involvement (pagetoid spread, nesting of cells, trans-epidermal elimination) according to the age of the patients. 89 cases of Spitz nevus were reviewed. There were 19 compound Spitz nevi with evidence of epidermal involvement, 56 cases of compound Spitz nevi without evidence of epidermal involvement and 14 cases of dermal Spitz nevi. The epidermal involvement mainly consisted of nesting of nevus cells above the basal cell layer, 9 cases clearly showing evidence of transepidermal elimination of cell nests. Upward spread of single melanocytes (pagetoid spread) was minimal and always associated with nesting or trans-epidermal elimination. The mean age of patients was significantly lower in the group of compound nevi with intraepidermal involvement (7.16 +/- 4.52 years), than in the group of compound nevi without epidermal involvement (13.18 +/- 8.88 years). The age of the latter group was significantly lower than the group of pure intradermal nevi (30.14 +/- 11.25 years). Thus, involvement of the suprabasal epidermis is not a feature of Spitz nevi in adults; in such a case the diagnosis of malignant melanoma should be considered.

Merkel cell hyperplasia in hypertrophic varieties of actinic keratoses.

Hyperplasia and dysplasia of the epidermal neuroendocrine cells (i.e., Merkel cells, MC) have been suggested in lesional skin of actinic keratosis and chronic radiation dermatitis. Because several histological types of actinic keratosis exist, we investigated the occurrence of such MC hyperplasia according to each of the histological patterns. Using an immunoperoxidase technique and the cytokeratin monoclonal antibody CAM 5.2, we counted 0.02 CAM 5.2 + cells (i.e., MC)/mm epidermis in normal-appearing perilesional skin; 0.05 MC/mm epidermis in nonhypertrophic actinic keratoses and 4.09 MC/mm epidermis in hypertrophic actinic keratoses. This number was as high as 14.40 MC/mm epidermis when hypertrophic actinic keratoses showed club-like epithelial proliferations. In contrast to normal epidermis, where MC were found isolated within the basal cell layer, MC clustered in these club-like epithelial proliferations as they did in the normal parakeratotic zone of the rabbit lip epithelium. The significance of this selective MC hyperplasia is discussed.

Melanoacanthoma of the penis shaft. Report of a case.

We report an additional case of melanocanthoma, a rare benign mixed tumor of both keratinocytes and melanocytes occurring in a 66-year-old man on the penis shaft, a localization not previously described. Clinical and histological features are briefly discussed.

Acquired epidermal cysts and mycosis fungoides. A possible pitfall in clinical staging.

A 60-year-old man was followed for 5 years for plaque stage mycosis fungoides (MF), follicular mucinosis (FM), and multiple recurrent acquired epidermal cysts on the face, scalp, right axilla, and inguinoscrotal areas. Topical nitrogen mustard and steroids, as well as systemic retinoids controlled the infiltrated lesions of MF, but had no effects on the cysts, which had to be removed surgically. Such cases have to be distinguished from MF in a tumor stage and may suggest that the recurrent cysts represent a paraneoplastic syndrome.