Large-cell acanthoma. A distinctive keratosis.

Large-cell acanthoma is an epidermal neoplasm that is clinically, histologically, and biologically distinctive. Clinically, it differs from solar lentigo by being frequently skin-colored or hypopigmented. Histologically, it is defined by a population of uniformly large keratinocytes; it differs from solar lentigo by the absence of elongated hyperpigmented and sometimes hockey stick-shaped buds of keratinocytes. Biologically, it consists of hyperploid keratinocytes, whereas solar lentigo consists of diploid keratinocytes. Although the exact nosologic status of this entity is still controversial, its features are distinctive enough for the term "large-cell acanthoma" to merit continued usage.

Present status of eyelid phototherapy. Clinical efficacy and transmittance of ultraviolet and visible radiation through human eyelids.

BACKGROUND: Phototherapy for the eyelid has not previously been recognized as a safe and effective treatment of photoresponsive dermatoses of the eyelid, such as atopic dermatitis, vitiligo, psoriasis, lymphomatoid papulosis, and parapsoriasis. OBJECTIVE: The purpose of this study was to demonstrate the efficacy and safety of this treatment. METHODS: Two cases are presented to demonstrate clinical efficacy. In addition, a retrospective eye evaluation of seven patients receiving a combined total of greater than 1300 eyelid phototherapy treatments was performed. To determine whether potentially harmful UV radiation is significantly transmitted through eyelid skin, an in vitro study was conducted to measure the percentage transmittance of ultraviolet-visible radiation through five excised eyelids. RESULTS: In the two cases presented, remarkable improvement occurred without adverse side effects, suggesting that it is possible to deliver incremental UV dosages to eyelid skin to achieve clearing of skin disease. Retrospective analysis of patients' records revealed no ocular disease from the phototherapy. In vitro eyelid examination produced data that indicated negligible quantities of UV radiation were transmitted through eyelid skin compared with the visible spectrum, in which up to 77% of the radiation was transmitted through the tissue. CONCLUSION: The combined clinical experience and transmittance data suggest that eyelid phototherapy is a safe and effective treatment in selected patients.

Reticular erythematous mucinosis syndrome: review of the world literature and report of the syndrome in a prepubertal child.

An 8-year-old boy with reticular erythematous mucinosis syndrome had erythematous plaques on his chest, face, and arms for three years. Sun exposure resulted in pruritus and increased lesions. Histologic examination revealed a perivascular mononuclear cell infiltrate with hematoxylin and eosin staining, positive staining material between the dermal collagen bundles with alcian blue (pH 2.5) staining, and granular basement membrane deposits of IgM with direct immunofluorescence staining. Results of all lupus erythematosus serologies and porphyrin studies were negative. Minimal erythema dose determinations to ultraviolet A and B were normal, and the lesions could not be induced with high doses of irradiation. Topical sunscreens, corticosteroid cream, and systemic beta-carotene produced no therapeutic benefit.

Multiple minute palmar-plantar digitate hyperkeratoses.

Digitate hyperkeratoses are rare lesions of unknown cause. We wish to add a new variant of this entity to the few reports in the literature. Our patient is a 79-year-old woman with palmar pits and digitate hyperkeratoses limited to her palms and soles.

Interdigital angioleiomyoma.

A painful mass in the interdigital space may represent an angioleiomyoma. Complete surgical excision followed by histologic examination is the optimal approach to diagnosis and therapy.

Pathology of melanoma.

The biologic behavior of several common clinicopathologic types of melanoma is generally predictable by the depth of tumor invasion. However, some individuals have tumors that do no behave as predicted. These include what some authors have called borderline melanoma and minimal deviation melanoma as well as desmoplastic melanoma, thin superficial spreading melanoma with marked regression, and melanomas arising within some nevi. The reasons for the erratic behavior of these melanomas remains enigmatic.

Eosinophils in the cellular infiltrate of granuloma annulare.

Eosinophils have been described in the infiltrates of granuloma annulare, but their frequency, distribution and extent are not well documented. We found eosinophils in 18/45 (40%) cases of granuloma annulare, without significant variation relating to histologic sub-pattern. Eosinophils were seen in over half the cases of deep granuloma annulare and in over one-third of the cases of superficial granuloma annulare. This study demonstrates the lack of specificity of eosinophils in differentiating superficial granuloma annulare from deep granuloma annulare, granuloma annulare from necrobiosis lipoidica, and granuloma annulare from occasional clinical simulants which histologically show eosinophils, such as arthropod bite reactions.

Multiple large cell acanthomas.

Large cell acanthoma is a benign keratosis which occurs as a generally hyperkeratotic, sharply demarcated patch on actinically exposed skin. Clinically, it is usually misdiagnosed as a seborrheic keratosis or solar keratosis. The first two reports of multiple large cell acanthomas are described here. Clinical and histologic features were identical to a control series of sixteen solitary large cell acanthomas. Large cell acanthomas should be considered in the differential diagnosis of solitary and multiple keratoses on sun-exposed skin.

The invisible dermatoses.

It is understandable that clinically normal skin may show abnormalities when examined with the light microscope, but paradoxical that biopsy of a clinically significant skin disorder may show a histologic picture that looks like normal skin. From the perspective of the dermatopathologist, the invisible dermatoses are clinically evident skin diseases that show a histologic picture resembling normal skin. A strategy for approaching the problem of the invisible dermatoses is to first examine the epidermis for fungi, cornoid lamellae (disseminated superficial actinic porokeratosis), and absence of the granular layer (dominant ichthyosis vulgaris). The cutis is then studied for hyalin deposition (macular amyloidosis), mast cells, microfilaria, dermal melanocytosis, silver granules, and absence of sweat glands (anhidrotic ectodermal dysplasia). Special stains may be required to uncover conditions like anetoderma and nevus elasticus. Comparison of the specimen with normal skin may disclose atrophoderma, lipoatrophy, vitiligo, or café au lait spot. Finally, technical problems should be considered, including sampling errors and mixup of specimens, either by the clinician or the laboratory.

Pigmentary correction of piebaldism by autografts. I. Procedures and clinical findings.

Full-thickness and epidermal autografts of normally pigmented skin were transplanted within hypopigmented areas in each of two patients with piebaldism. Full-thickness punch grafts 2 to 4 mm in size retained their pigmentation (donor dominance) and within 4 months pigment was found to have spread around them. Within a year, melanization covered roughly triple the diameter of the grafts (or 9 times their areas) and then came to a standstill. Epidermal grafts (about 12 mm in diameter) healed with no visible scars at either donor or recipient sites. These grafts, too, retained their pigmentation, but no pigment was seen to spread from them in 8 months of observation. Controls of hypopigmented, full-thickness autografts placed into comparable hypopigmented areas showed either no change or but slight pigmentation along the rim of the graft and no spread of pigment.