Clear Cell Acanthoma Research Articles

Multiple Clear Cell Acanthomas

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.

On the nature of clear cell acanthomas.

Five clear cell acanthomas were studied using a panel of immunohistological markers. The results were compared with those from basal cell papillomas, with and without clear cell change, and with lesions of psoriasis and lichen planus. The results do not support the contention that these lesions are variants of basal cell papillomas nor that they are true neoplasms.

Involucrin expression in skin appendage tumours.

The expression of involucrin was examined in 23 skin tumours of hair follicle origin, 17 tumours of sweat gland origin and three tumours of unknown origin, using an immunoperoxidase technique. All tumours from the hair follicle showed a positive reaction for involucrin. In particular keratoacanthoma and the squamous eddies in various tumours stained strongly. Trichofolliculoma, trichilemmoma and pilomatrixoma exhibited characteristic staining patterns which resembled those in the normal hair follicle. On the other hand the majority of the tumours of sweat gland origin did not stain, with restricted positive reactions in areas showing lumen formation or squamous metaplasia. In contrast to the lack of staining in syringoma, a positive reaction was observed in desmoplastic trichoepithelioma, which is histologically similar to syringoma. Clear cell acanthoma, the origin of which is still controversial, showed a staining pattern which indicated that its origin may not be in the sweat gland. These results suggest that testing for involucrin in skin appendage tumours may be very useful for understanding the kinetics of maturation as well as in determining the origin of the tumours.

Multiple clear cell acanthomas: Case report and delineation of basement membrane zone antigens

A case of multiple clear cell acanthomas is described with a review of the literature. This benign glycogen-rich epidermal tumor is generally unable to accept melanin and lacks phosphorylase or cytochrome oxidase activity. However, the basement membrane zone appears antigenically normal, as documented by the presence of epidermolysis bullosa acquisita antigen, bullous pemphigoid antigen, heparan sulfate proteoglycan, type IV collagen, and laminin by immunofluorescence microscopy.

The benign acanthomas.

An important, yet neglected, problem in dermatopathology, is the evaluation of the benign acanthomas, the benign tumors of epidermal keratinocytes. The benign acanthomas may be simulated by lesions which are not benign (e.g. actinic keratosis), not tumors (e.g. normal plantar skin), or are not epidermal (e.g. dermatofibroma). In addition to normal (epidermoid) keratinization (e.g., seborrheic keratosis and related conditions), the variants of the benign acanthomas show a wide range of aberrant keratinization, including epidermolytic hyperkeratosis (epidermolytic acanthoma), dyskeratosis (warty dyskeratoma), acantholysis (acantholytic acanthoma), cornoid lamellation (porokeratosis), lichenoid hyperplasia (lichen planus-like keratosis), and absence of keratinization (clear cell acanthoma).

Multiple Clear Cell Acanthomas

In 1962, Degos et al¹described an uncommon benign skin tumor, histologically identifiable by sharply demarcated, regular acanthosis. They named it clear cell<i>acanthoma</i>. Under microscopic examination, the tumor was found to consist of pale epidermal cells containing abundant amounts of glycogen, as evidenced by PAS-positive and diastase labile stains. Further clinical and histologic characterization followed publication of this report.^2,3 The acanthoma arises as an asymptomatic, single, erythematous papule or plaque, measuring 5 to 10 mm in diameter. It occurs in both sexes, usually in midlife. It most commonly appears on the lower part of the leg, especially on the calf. A fine, scaly layer may cover the tumor, which blanches on diascopy and bleeds easily with minor trauma, mimicking a pyogenic granuloma. The solitary clear cell acanthoma is an uncommon tumor. Multiple lesions, however, are truly rare, with only 12 cases reported to date. We report herein

Clear cell acanthoma: not of sweat gland origin

Abstract not available

Multiple Clear Cell Acanthomas

Clear cell acanthoma is usually a solitary benign epidermal tumor. Multiple lesions are rarely encountered, and only 11 such cases could be found in the literature. In all cases, the lesions were limited to the lower extremities. A few of the patients have had ichthyosis and/or varicose veins. We describe a 12th patient who, in addition to leg lesions, had lesions on the trunk and associated dry skin.

Multiple clear cell acanthomas

† Clear cell acanthoma is usually a solitary benign epidermal tumor. Multiple lesions are rarely encountered, and only 11 such cases could be found in the literature. In all cases, the lesions were limited to the lower extremities. A few of the patients have had ichthyosis and/or varicose veins. We describe a 12th patient who, in addition to leg lesions, had lesions on the trunk and associated dry skin. (<i>Arch Dermatol</i>116:433-434, 1980)

Clear Cell Acanthoma: A Widely Unknown Tumor-like Dermal Lesion

Clear Cell Acanthoma: A Widely Unknown Tumor-like Dermal Lesion

Clear-cell acanthoma of vermilion mucosa of lower lip

A 63-year-old man with clear-cell acanthoma of the vermilion mucosa of the lower lip is reported. The 143 previously documented cases, including two on the lip, have all been on the skin. The clinical and histopathologic features of clear-cell acanthoma tend to favor a benign epidermal neoplasm. Until its exact nature is known, it is suggested that clear-cell acanthoma be considered a benign localized squamous-cell lesion in which an intracellular enzyme defect has resulted in the prominent accumulation of glycogen and enlargement of the cell.

Das Klarzellakanthom

In the last 6 years, 10 patients with a total of 17 clear-cell acanthomas were observed. All lesions but one were located at the legs. On the basis of this material the typical clinical picture as well as the histology and ultrastructure of these tumors is described.

Some evidence concerning the sweat duct origin of clear cell acanthoma

Abstract i not available.

Clear Cell Acanthoma: Clinicopathologic Analysis of 37 New Cases

The clinical and histologic features of 37 new cases of clear cell acanthoma were analyzed. All lesions were solitary; most were asymptomatic, erythematous nodules less than 1 cm. in diameter. The median age of the patients was 64 years, the median duration of the lesions was 3 years, and the incidences in both sexes were equal. Thirty-five of the tumors occurred on the lower limbs. Many were clinically interpreted as basal cell carcinoma, histiocytoma, or granuloma pyogenicum. Histologic examination disclosed acanthotic rete ridges with large, pale, glycogen-rich malpighian cells covered by serous crust and parakeratotic scale. At each margin there was a sharp transition to dark cell acanthosis in two or three rete ridges which were covered by thick horn and a hyperplastic granular layer. Lateral to this was a second transition to normal epidermis. Rich vascularity and a perivascular lymphocytic infiltrate were present in the cutis.

Multiple Clear-Cell Acanthoma and Ichthyosis

One patient with lamellar ichthyosis and one patient with ichthyosis vulgaris, both with multiple clear-cell acanthomas on the lower extremities, were studied. Histologic examination showed the typical findings of clear-cell acanthoma, plus intraepidermal nests composed of cell debris and inflammatory cells. Histochemical studies revealed increased dendritic cells with intense nucleotide triphosphatase and acid phosphatase activities. The dendritic cells also contained neutral lipids, well demonstrated by oil red O stain. Electron microscopic examination revealed, in addition to glycogen-containing epidermal cells, dendritic cells and processes in the intercellular spaces. Although indeterminate dendritic cells were found, many contained Langerhans granules and lysosomes. Leukocytes and products of cell degradation were seen in the intercellular spaces, often in relation to the leukocyte nests. Mast cells were observed in the epidermis.

Multiple clear cell acanthomas in a patient with lamellar ichthyosis.

Clear cell acanthoma is a benign neoplasm of keratinocytes usually occurring as a single lesion and not found with an underlying skin disorder. A patient is reported with generalized lamellar ichthyosis and scattered clear cell acanthomas. The meaning of this unique association remains obscure and is in all probability coincidental.

Clinical Recognition of Clear-Cell Acanthoma (Degos')

We are reporting four additional patients with typical Degos' clear-cell acanthomas to emphasize that a clinical diagnosis is possible. A single, 1- or 2-cm, slowly growing, domeshaped, sharply delineated, erythematous, usually smooth papule, stippled with tiny red puncta which blanche on pressure and marginated by a thin keratinous scale, suggests the diagnosis. Presurgical recognition may avert unnecessary radical treatment.

Clinical recognition of clear-cell acanthoma (Degos')

Clinical recognition of clear-cell acanthoma (Degos')