Xanthogranuloma in adults.

Nine cases of cutaneous xanthogranuloma in adults are reported. These lesions were histologically indistinguishable from the xanthogranulomas in infants and children (juvenile xanthogranuloma), and, like those in the young, they were not associated with abnormalities of serum lipids. Unlike juvenile xanthogranuloma, however, in our small sample there was no concomitant involvement of the eye in adult xanthogranuloma.

Pseudomelanoma: recurrent melanocytic nevus following partial surgical removal.

Histological markers enable the correct diagnosis of a pigmented lesion that histologically resembles a superficial spreading malignant melanoma and yet behaves in a wholly benign way. This pseudomelanoma occurs in young adults within a few weeks following partial surgical-shave excision of an intradermal melanocytic nevus.

Persistent acantholytic dermatosis. A variant of transient acantholytic dermatosis (Grover disease).

A patient with unusual manifestations of transient acantholytic dermatosis (Grover disease) has lesions that have persisted for more than three years. Biopsy specimen showed histologic changes previously unreported in Grover disease. In order to emphasize that this condition is not always transient, we have titled this entity "persistent acantholytic dermatosis."

Epidermotropically metastatic malignant melanoma. Differentiating malignant melanoma metastatic to the epidermis from malignant melanoma primary in the epidermis.

In four instances, metastases to epidermis from primary cutaneous malignant melanomas at different sites showed histological features similar to those of cutaneous malignant melanoma primary in the epidermis. In these metastases, atypical melanocytes were present within the epidermis and in the upper part of the dermis much as in primary cutaneous malignant melanoma. Therefore, the presence of atypical melanocytes within the epidermis is not in itself an absolute criterion of malignant melanoma primary in skin. Nor does that finding absolutely deny malignant melanoma metastastic to the skin. Features that may enable histologic differentiation of epidermotropically metastatic malignant melanoma from primary cutaneous malignant melanoma are emphasized.

Angiolymphoid hyperplasia with follicular mucinosis.

Follicular mucinosis is described to our knowledge for the first time in angiolymphoid hyperplasia. In general, follicular mucinosis may be regarded as a peculiar, nonspecific histological reaction pattern in follicular epithelium that may occur on its own or in association with other pathological processes, particularly lymphomas. The unusual and characteristic features of angiolymphoid hyperplasia revealed by electron microscopy are irregular vessels lined by atypical endothelial cells with convoluted nuclei and large cytoplasmic vacuoles.

Pathologic findings in human scabies.

The histologic findings in the papular, vesicular, nodular, and Norwegian variant of scabies have in common a superficial and deep perivascular mixed inflammatory cell infiltrate of lymphocytes, histiocytes, and numerous eosinophils. A spongiotic vesicle occurs in the papulovesicular type, a dense cellular infiltrate in the nodular type, and a hyperkeratotic psoriasiform dermatitis in the Norwegian type. Eggs, larvae, and adult mites are abundant in the cornified layer of Norwegian scabies, are practically never found in biopsy specimens from lesions of nodular scabies, and are discovered only episodically in papulovesicular lesions.

Transient acantholytic dermatosis: a reevaluation.

Transient acantholytic dermatosis is a self-limited, primary acantholytic disease that occurs predominantly in persons over 50 years old. The primary lesions, discrete papules and papulovesicles, are distributed mainly on the chest, back, and thighs and may be intensely pruritic. The disease lasts less than three months in the majority of patients, but occasionally may go on for two or three years. Four distinct histologic patterns are present in the biopsy specimens, namely, Darier-like in which there is focal acantholysis and dyskeratosis overlying suprabasilar clefts; pemphigus vulgaris-like, in which there are a few acantholytic cells above discrete suprabasal clefts having a mostly intact overlying epidermis; Hailey-Hailey-like, in which there are numerous acantholytic cells overlying suprabasilar clefts; and, finally, spongiotic, in which a few acantholytic cells are present within, or contiguous with, spongiotic foci. Some cases show a predominance of one pattern, but more frequently two or more of these patterns can be found in a single biopsy specimen.

Herpes gestationis. A clinicopathologic study.

Herpes gestationis is a pruritic, blistering eruption of pregnancy and the puerperium. In three patients with immunologically verified disease, the clinical presentation consisted of widespread erythematous, edematous papules and plaques, grouped vesicles on erythematous bases, and tense bullae. Histologically, these lesions showed a moderately dense, mixed-inflammatory cell infiltrate around superficial and deep dermal blood vessels, and focal necrosis of epidermal basal cells. Papillary dermal edema, subepidermal bullae, and spongiosis were prominent. Eosinophils were frequently present in the subepidermal and intrepidermal vesicles. Differentiation of herpes gestationis from other blistering diseases and other dermatitides of pregnancy may be difficult.

Nevus of large spindle and/or epithelioid cells (Spitz's nevus).

By now it is well recognized that there is a benign melanocytic nevus, common in the young and common enough in adults, that has histological features that are confusable with those of malignant melanoma. The anomaly is usually referred to as benign juvenile melanoma, sometimes as Spitz's nevus, and, by some histopathologists, as spindle and epithelioid cell nevus. All the histological subtleties and variations of the condition are still not fully appreciated and some of them are still being misinterpreted as those of malignant melanoma. We herewith present a study designed to clarify the issue and offer firm criteria for histological differentiation of the nevus in point from malignant melanoma. We also suggest a new name for it and supporting arguments therefor.

Bowenoid papulosis of the genitalia.

We report 34 cases of bowenoid papulosis of the genitalia. In each case, the patient had numerous reddish brown or violaceous papular lesions, some distinctly verrucoid, situated on the genitalia. Although clinically the lesions invariably appeared benign, histologic examination of specimens from the genital lesions in each patient showed changes of squamous cell carcinoma in situ. Many of the patients gave a history of preceding viral lesions on the genitalia. Therapy in all cases was conservative but thoroughly ablative. We view bowenoid papulosis as a new entity whose biologic behavior if untreated is as yet unknown.

Malignant melanoma in situ: the flat, curable stage of malignant melanoma.

Malignant melanoma can be diagnosed clinically and histologically when it is small, flat, and confined to the epidermis. The criteria for the diagnosis are described. The application of these criteria can lead to simple excision of the lesion and the prevention of the malignant melanoma from evolving into a neoplasm with the potential for metastasis.

Ancient melanocytic nevus.

Ancient melanocytic nevus is an example of a simulator of malignant melanoma, designated ancient because it shares numerous features with ancient schwannoma. Knowledge of the histopathologic characteristics of this benign melanocytic neoplasm should enable pathologists to avoid overdiagnosis of it as melanoma arising in the intradermal portion of a nevus. Ancient nevi are found most commonly on the face of older persons. The neoplasm is usually a dome-shaped, skin-colored or reddish brown papule, usually with features of a Miescher's nevus. Histopathologically, ancient nevi are exoendophytic, mostly intradermal proliferations of two populations of melanocytes: one with large pleomorphic nuclei and the other with small monomorphous ones. The large melanocytes may resemble those of the epithelioid type of Spitz's nevus. A few mitotic figures may be present in a particular section. The epidermis usually is uninvolved, but sometimes there may be a junctional component. Other important findings are degenerative changes that include thrombi, zones of hemorrhage, pseudoangiomatous changes, thick rims of sclerosis around dilated venules, fibrosis, and mucin. Ancient nevi frequently are misdiagnosed as melanoma arising in an intradermal nevus.

Subcorneal pustular dermatosis: a variant of pustular psoriasis.

A patient with clinical lesions typical of subcorneal pustular dermatosis of Sneddon and Wilkinson also had stigmata of psoriasis, namely psoriatic plaques, pitting of nails, and psoriatic arthritis. Histologic studies of the pustular lesions were consonant with pustular psoriasis. Correlating the phenomena of previously reported cases of subcorneal pustular dermatosis with those of our patient, we conclude that subcorneal pustular dermatosis of Sneddon and Wilkinson is but another variant of psoriasis.

Acneform lesions in Becker's nevus.

Three cases of Becker's nevus are described in which acneform lesions were confined strictly within the limits of the hyperpigmentation. The combined phenomenon has not been reported previously, and we conceive it to be either a rare variant of the anomaly or a still rarer coincidence of Becker's nevus and nevus comedonicus.

The "vanilla fudge" cyst.

A white cyst, partially covered by jet black splotches and streaks, had a surface appearance of vanilla fudge ice cream. Histologically, the cyst was lined with two distinctly different types of follicular epithelium--one identical to that of the infundibulum and the other to that of the matrix. The black pigment was melanin, produced by numerous dendritic melanocytes that were situated only in the region of the epithelium-resembling matrix.