Won Hyoung Kang

Nevus comedonicus associated with epidermal nevus

A 21-year-old man had a zosteriform nevus comedonicus associated with a surrounding hyperpigmented maculopapular eruption, which had the histologic appearance of epidermal nevus. Scanning electron microscopic examinations of the comedones and the surrounding epidermal nevus showed a common feature, that is, chrysanthemum-like keratotic plugs. The association of a nevus comedonicus with an epidermal nevus and the common scanning electron microscopic findings of both suggest that a nevus comedonicus probably is an uncommon form of epidermal nevus.

Confluent and Reticulated Papillomatosis: A Clinical, Histopathological, and Electron Microscopic Study

The clinical, histopathological, and electron microscopic features often patients with confluent and reticulated papillomatosis (CRP) of Gougerot and Carteaud were studied. Histopathologically, hyperkeratosis, decreased granular layer, irregular papillomatosis, and hypermelanosis of the basal layer were present. In an electron microscopic study, we found transitional cells between the stratum granulosum and stratum corneum that were increased in CRP. This finding supported the suggestion that this is a defect of keratinization.

Eosinophilic ulcer of oral mucosa

A 41‐year‐old woman was seen for the examination of a painless lesion on the posterior hard palate of 2 weeks’ duration. She had no systemic symptoms. Examination of the hard palate showed a single 1 × 1 cm, round, punched out ulcer with an erythematous base; the margins of the ulcer were slightly raised and indurated ( Fig. 1 ). Other clinical findings were normal and laboratory study of a cutaneous biopsy showed necrotic ulceration with dense inflammatory cell infiltration. An extensive inflammatory cell infiltration with predominantly eosinophilic cells was present throughout the submucosa. A single application of liquid nitrogen decreased the lesion.

Cutaneous Reaction Induced by Retained Bee Stinger

The clinical features and histopathologic findings of a 54‐year‐old Korean male who had retained the sting apparatus of a bee for four months are described. The clinical features showed ulcerative, erythematous plaques with irregular borders which resembled cutaneous neoplasms such as squamous cell carcinoma. Histopathologic findings included epidermal necrosis and marked pseudoepitheliomatous hyperplasia. In the dermis, the stick‐shaped sting apparatus of the bee was demonstrated and intense lymphohistiocytic and eosinophilic infiltrations were noted.

Self limited dermal invasion of keratinocytes in maculopapular eruptions after systemic chemotherapy.

Benign, multifocal, and transient (spontaneously disappearing within one month) stromal invasions of atypical basal keratinocytes were found in light and electron microscopic examination of maculopapular eruptions which developed after receiving an 8 day cycle of doxorubicin, 5‐fluorouracil (5‐FU), and cyclophosphamide (Cy) in a 63‐year‐old woman. She had had a modified radical mastectomy to remove a carcinoma of her right breast.