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L Requena

Publications and source records attributed to L Requena.

At least 109 records · Page 6Linked to original sources
PubMed1995

The atrophic dermatofibroma: a delled dermatofibroma.

Atrophic dermatofibroma has been proposed as a term to designate a new and specific type of dermatofibroma. We report the clinical and histopathological findings in two cases of atrophic dermatofibroma. The peculiar morphology of these lesions simply represents a conspicuous example of the frequently seen central depression in dermatofibroma. On histopathology, no authentic atrophy is present, because the thinning of the dermis compared with that of the adjacent non-lesional skin results from this depression rather than from loss of tissue of the dermis. Delled dermatofibroma is a more appropriate appellation than atrophic dermatofibroma, because of the striking shape of these lesions.

Arm↗
PubMed1995

Multiple hidrocystoma of the face: three cases.

Multiple hidrocystomas of the face (Robinson type) is an uncommon variant of hidrocystoma consisting of multiple cysts of the face of middle-aged women with exacerbation in hot temperatures. Controversy about the eccrine or apocrine nature of these lesions has appeared in the literature almost since their original description in 1893. Immunohistochemistry is not helpful in distinguishing between eccrine and apocrine differentiation in these lesions and enzyme histochemical studies have not been conclusive. We report three patients with this rare variant of hidrocystoma. In our opinion, multiple hidrocystomas of the face are apocrine hidrocystomas in which characteristic 'decapitation' secretion has been effaced by the pressure of cyst contents against the lining epithelium; only after serial sections is it possible to identify some areas of the cyst lining showing apocrine secretion in the luminal border of columnar cells.

Facial Dermatoses↗
PubMed1995

Verruciform xanthoma of the penis with acantholytic cells.

Verucciform xanthoma is an unusual lesion characterized by verrucous epithelial proliferation accompanied by a prominent replacement of the dermal papillae with foamy histiocytes. We describe a case of verruciform xanthoma on the glans penis. The most striking histopathological finding was the presence of numerous acantholytic cells in the upper layers of the epithelium. We discuss the differential diagnosis with other acantholytic disorders of the genital area and conclude that our findings can be interpreted as an additional example of incidental acantholysis.

Acantholysis↗
PubMed1995

Subcutaneous juvenile xanthogranuloma.

A 1-month-old female infant was seen in consultation because of a congenital subcutaneous nodule, 2 x 3 cm in diameter, in the right retroauricular area. The nodule was surgically excised. Histologically, a large subcutaneous nodular mass was well delimited but not encapsulated. It consisted of a monomorphous sheet of foamy histiocytic cells with scattered eosinophils. Multinucleated giant cells were not found. The pure subcutaneous type of juvenile xanthogranuloma has been reported very rarely in the literature. The usual histological monomorphism of these cases, with only occasional eosinophils and lymphocytes and rare Touton giant cells, adds another diagnostic difficulty to their unusual clinical presentation.

Female↗
PubMed1995

Malignant hidroacanthoma simplex. A case report and literature review.

A 73-year-old woman with a malignant hidroacanthoma simplex on her right lower limb is reported. The lesion was immunohistochemically studied. Carcino-embryonic antigen and epithelial membrane antigen were found in the luminal border of ductal structures within the aggregations of neoplastic cells. We review the literature on this subject.

Acrospiroma↗
PubMed1995

Tripe palms: a cutaneous marker of internal malignancy.

Tripe palms is a distinctive paraneoplastic cutaneous sign which is frequently associated with internal malignancy, specially carcinomas of the lung and stomach. We describe a patient with ovary carcinoma who showed a curious rugose thickening of the palms with accentuation of the normal dermatoglyphic ridges. The lesions were a specially prominent on the fingertips. The patient also showed classical acanthosis nigricans in the axillae and groin. The soles were spared. Histopathologic findings in palmar lesions consisted of an undulant epidermis, with hyperkeratosis, acanthosis, and papillomatosis. Excision of the ovary carcinoma was followed by complete regression of the cutaneous lesions. We review the literature about tripe palms and discuss the relationship between this striking cutaneous manifestation and internal malignancy.

Acanthosis Nigricans↗
PubMed1994

Multiple primitive neuroectodermal tumors.

Primitive neuroectodermal tumors are rare, highly aggressive neoplasms that affect both sexes and occur in all age groups. They are a large group of neoplasms with neuroepithelial differentiation, including cutaneous neuroblastomas. Histopathologically they are characterized by a rather uniform population of small, dark cells, with or without Homer Wright rosettes. Immunohistochemically they stain for one or more of the reputed neural markers. Ultrastructurally they show interdigitating processes containing neurosecretory granules, intermediate filaments, and microtubules. We describe a patient with unusual multiple peripheral neuroectodermal tumors localized to the skin, with benign biologic behavior. The patient related the appearance of new lesions for several years without evidence of visceral dissemination or systemic complications. The histopathologic, immunohistochemical, and ultrastructural findings support the diagnosis of a peripheral neuroectodermal tumor.

Diagnosis, Differential↗
PubMed1994

Neurofollicular hamartoma. A new histogenetic interpretation.

Neurofollicular hamartoma is a recently described entity characterized histopathologically by fascicles of spindle cells that are haphazardly arranged and laterally delimited by hyperplastic folliculo-sebaceous units. Immunohistochemical studies have shown the presence of a few S-100-positive cells scattered among the spindle cells. We report five cases of this peculiar entity and compare them to two examples of trichodiscomas. Both hamartomas were characterized by proliferations of spindle cells in close association with prominent folliculo-sebaceous units. Based on the clinical and histopathological findings, as well as the immunoperoxidase stains, we conclude that neurofollicular hamartomas are not different from trichodiscomas and fibrofolliculomas.

Adult↗
PubMed1994

Clinical and histological patterns of dermatofibromas of the nail apparatus.

True fibromas develop as painless slow-growing nodular tumours. They may appear in any portion of the nail apparatus. The clinical features vary according to their anatomical site. In contrast, the histological features, consisting of a dermal hypocellular reticular nodule with ill-defined demarcation, were similar in all our patients, and factor XIIIa was negative.

Histiocytoma, Benign Fibrous↗
PubMed1994

Lymphoepithelioma-like carcinoma of the skin: a light-microscopic and immunohistochemical study.

Cutaneous carcinoma histopathologically resembling nasopharyngeal carcinoma has been termed lymphoepithelioma-like carcinoma of the skin. We present an additional example of this rare cutaneous neoplasm that was located on the left temple of an 83-year-old woman. Serology for Epstein-Barr virus was negative, and exploration of the nasopharyngeal region disclosed no abnormalities. Histopathologically, the neoplasm consisted of a relatively well-circumscribed, dermal-hypodermal nodule composed of irregular aggregates of epithelial cells with vesicular nuclei, some of them in mitosis, and scant cytoplasm. A dense lymphocytic infiltrate was present within the neoplastic aggregates, obscuring the epithelial component, and at scanning magnification, the lesion closely resembled cutaneous lymphoma or pseudolymphoma. There was focal sebaceous differentiation. Immunohistochemistry showed positivity in the epithelial component for AE1/AE3 and AEB-903 cytokeratins and negativity for 8-18 cytokeratins. The inflammatory infiltrate was positive for leukocyte common antigen, UCHL-1, L-26, Leu-22, and OPD-4 in variable proportions. Scattered cells within this inflammatory infiltrate were also positive for S-100 protein, vimentin, HAM-56, and MAC-387. In situ hybridization investigations for the presence of Epstein-Barr virus genomic DNA yielded negative results. Lymphoepithelioma-like carcinoma of the skin is a distinct cutaneous neoplasm of unknown histogenesis, although some foci of adnexal differentiation have been found in some specimens. The possibility of cutaneous metastasis from occult nasopharyngeal carcinoma should be ruled out.

Aged↗
PubMed1994

Annular atrophic lichen planus.

We describe the second case of annular atrophic lichen planus. The annular configuration of the lesions resulted from peripheral enlargement with simultaneous central clearing. Histology showed features of lichen planus in the active border of the lesion and a pattern of resolved lichen planus in its center. Elastic fibers had been destroyed in the papillary dermis both in the border and in the center of the lesion, resulting in an atrophic appearance of the lesion. Annular atrophic lichen planus is an uncommon variant of lichen planus that results from elastolytic activity of inflammatory cells with formation of areas of localized acquired cutis laxa.

Aged↗
PubMed1994

Giant dermatofibroma. A little-known clinical variant of dermatofibroma.

BACKGROUND: Dermatofibroma is a common cutaneous lesion that usually appears as a slow-growing firm dermal nodule. OBJECTIVE: Our purpose was to report the clinical and histopathologic characteristics of eight giant dermatofibromas and review the few cases of this variant of dermatofibroma reported in the literature. METHODS: All clinical records of two Departments of Dermatology of University Hospitals from the past 5 years with a diagnosis of dermatofibroma were reviewed. Lesions that measured 5 cm or larger were considered for this study. Biopsy specimens were available from all lesions. RESULTS: Giant dermatofibromas are most frequently on the legs, especially below the knee. Often they have a pedunculated appearance. Because of their large size, the correct diagnosis is not suspected clinically; a diagnosis of malignancy is often made. CONCLUSION: Our findings indicate that giant dermatofibroma is a distinct but uncommon clinical variant of dermatofibroma that invariably exhibits a benign biologic behavior.

Adult↗
PubMed1993

Histopathology of cutaneous changes in drug-induced coma.

Present knowledge of the histopathology of cutaneous changes seen in drug-induced coma is very incomplete: Only 1 of the 11 papers on this subject mentions follicular or sebaceous gland damage, with very little attention focused on vascular changes. We made a careful study of serial sections from eight cutaneous biopsy specimens from seven patients who suffered drug-induced coma with the following findings: (a) The secretory portion of the eccrine sweat coil is the epithelium most susceptible to necrosis. It is followed by, ex aequo, eccrine sweat duct, hair follicle, and sebaceous gland, and, lastly, the epidermis. (b) In the eccrine sweat duct, the outer root sheath of the hair follicle, and the epidermis, necrosis does not usually appear first in the outermost (basal cell) layer. (c) Necrosis of the outer root sheath of the telogen "club" follicle is usually more advanced than that of the secondary hair germ, and, at times, a spared anagen bulb can be seen in closest proximity. (d) Vascular changes correlate proportionately with epidermal damage and consist of a largely neutrophilic inflammatory infiltrate and blood vessel wall damage, mainly involving arterioles. Our findings contradict the widely accepted hypothesis that pressure is the main cause of the cutaneous changes in drug-induced coma.

Adult↗
PubMed1993

Giant trichoblastoma on the scalp.

We describe a case of giant trichoblastoma that had been present for many years on the scalp of a 69-year-old man. The specimen was examined histopathologically, immunohistochemically, and ultrastructurally. Histopathologic examination showed that neoplastic cells were arranged in different patterns from area to area, including rippled, adenoid, and palisading patterns. In some areas of the neoplasm, foci of sebaceous differentiation were also present. The ultrastructural characteristics of neoplastic cells support the notion that trichoblastomas are neoplasms composed mostly of follicular germinative cells.

Aged↗
PubMed1993

Incidental acantholysis.

The incidental finding of microscopic foci of acantholytic dyskeratosis, reproducing the histological pattern of Darier's disease, has been the subject of a number of papers in the last few years. In contrast, the incidental finding of other types of acantholysis has not been mentioned in the literature. In the last 5 years, we have noticed such a microscopic finding in 14 biopsy specimens (0.15% of our cutaneous specimens). they were from 13 patients (7 men and 6 women); their ages ranged from 37 to 79 years (mean, 63). Three lesions were located on the head, 7 on the trunk, and 4 on the limbs. The histological diagnoses were basal cell carcinoma (6 cases), keratoacanthoma (2 cases), psoriasis (2 cases), elastolytic granuloma, acral arteriovenous angioma, tinea corporis, and leukocytoclastic vasculitis (1 case each). The histological patterns of the acantholytic foci simulated pemphigus vulgaris (9 cases), superficial pemphigus (1 case), Hailey-Hailey disease (3 cases), and unclassifiable acantholysis (1 case). None of the patients had familial or personal history of acantholytic disorders. We propose a classification of the primary acantholytic disorders based on both their acantholytic pattern and their clinical extent.

Acantholysis↗