Lentigo senilis and its evolutions.

Histologic studies have shown the evolution of lentigo senilis and have established the relationship between lentigo senilis, solitary lichen planus-like keratosis, and the reticulated form of seborrheic verruca. Histologic differentiation can be made between lentigo senilis and the early light-brown stage of lentigo maligna.

Monoclonal antibody (AFH1) immunoreactive on morphologically abnormal basal melanocytes within dysplastic nevi, nevocellular nevus nests, and melanoma.

The mouse monoclonal antibody AFH1 was produced using formalin-fixed, sham paraffin-embedded human melanoma cell culture line A375 as immunogen. Reactivity of this antibody was assessed by immunohistochemical techniques against formalin- or acid alcohol-fixed paraffin-embedded tissue as well as formalin- or acid alcohol-fixed unembedded lesions. Ninety-seven nevomelanocytic lesions, neurofibromas, epithelial lesions, and a plasmacellular infiltrate were evaluated. AFH1 was immunoreactive on 54 of 55 nevocytic lesions (98.2%), 15 of 16 primary melanomas (93.7%), a lentigo maligna, and nests in 21 of 21 dysplastic nevi (100%). Of 100 consecutive basal melanocytes of intraepidermal melanoma cells counted in each lesion, mean AFH1 immunoreactivity for nonnested basal melanocytes in nevocellular nevi was 3.8%; for dysplastic nevi, 13.8%; and for intraepidermal melanoma cells, 78.0%. When nonnested basal melanocytes were subdivided into cytologically normal and abnormal cell groups, AFH1 immunoreactivity was 9.4% and 72.6%, respectively. AFH1 recognition of the lentiginous portion of dysplastic nevi corresponds statistically to the appearance of abnormal melanocyte cytology, nest formation, or both. Using 50% immunoreactive nonnested melanocytes as the criterion, AFH1 seems to distinguish primary melanoma from dysplastic nevi with a sensitivity of 93.8% and a specificity of 95.8%.

Monoclonal antikeratin antibody: production, characterization, and immunohistochemical application.

A monoclonal antikeratin antibody, EKH4, was produced from a hybridoma cell line which was established by fusing P3X63SAg8 mouse myeloma cells with spleen cells of mice immunized with human trichilemmoma cells. Immunoblot analysis showed that EKH4 antibody reacts predominantly with 50 kilodalton keratin polypeptide in normal epidermis. By indirect immunofluorescence and immunoperoxidase techniques, EKH4 antibody reacted with the lower 2-3 cell layers of the epidermis as well as most cells of pilosebaceous follicle of human and animal skin. Tumor cells of human basal cell epitheliomas and squamous cell carcinomas were also stained with this antibody. The staining was much more regular and intense compared with an available monoclonal antikeratin antibody, AE1. In the lesion of epidermal proliferative disorders, such as psoriasis and actinic keratosis, the entire epidermis instead of the lower layers was stained with EKH4 antibody. Normal skin overlying or adjacent to epithelial tumors also showed positive staining in the entire epidermis. By using indirect immunoperoxidase technique, EKH4 also stained alcohol-fixed, paraffin-embedded tissue sections.

Malignant blue nevus: a report of eight cases.

Malignant blue nevus is uncommon compared to its benign counterpart and is regarded as a rare form of malignant melanoma. We report the clinical and histological findings in eight cases. Histologically, all eight specimens showed no epidermal involvement and had contained within or were adjacent to portions of blue nevus or cellular blue nevus. Proliferation of bundles of bipolar spindle shaped cells with marked cellular atypia, mitotic figures, foci of necrosis, and inflammatory cell infiltrate were noted. Two of the cases were studied by DNA flow cytometry and the populations of tumor cells were found to be diploid. Two cases have died secondary to metastasis. Although malignant blue nevi may not behave as aggressively as nodular malignant melanoma, they have definite potential to do so and therefore should be removed by wide surgical excision.

Deep penetrating nevus.

BACKGROUND: Deep penetrating nevus is a variant of melanocytic nevi with histologic features that may be alarming and can be mistaken for malignant melanoma. We are presenting a review of the clinical findings and the histologic features of deep penetrating nevus in a series of 14 cases. OBSERVATIONS: Deep penetrating nevus occurs most commonly over the acral skin of young adults. Clinically, the lesions were diagnosed as pigmented nevus, blue nevus, or malignant melanoma. Histologically, deep penetrating nevus shows a wedge-shaped lesion extending to the deep dermis and the subcutaneous fat tissue. Nests and fascicles of pigmented melanocytes extended deep at the periphery of blood vessels, nerves, and the cutaneous adnexa. Low-grade cellular atypia is present and mitoses are rare. CONCLUSIONS: Deep penetrating nevus is a variant of benign pigmented nevi with deep dermal and subcutaneous involvement. The pattern should be recognized and differentiated from malignant melanoma.

Pilar sheath acanthoma.

A newly recognized, benign follicular tumor occurred in nine patients who ranged in age from 46 to 75 (median, 55) years. The neoplasms were solitary, asymptomatic, skin-colored nodules with a central pore-like opening plugged with keratin. All lesions had been present for years. Eight were on the skin of the upper lip and one was on the forehead. Histologically, a central cystic cavity showing epidermoid keratinization extended from the surface into the deep cutis. Multiple tumor lobules that were composed of hair sheath epithelium extended from the cyst wall into the surrounding corium. This neoplasm, which we have named "pilar sheath acanthoma," must be differentiated from trichofolliculoma and dilated pore.

Malignant angioendothelioma.

We have seen six cases of malignant angioendothelioma of face and scalp. This condition occurs most commonly in older individuals and is rapidly progressing. Large areas of infiltration of the skin appear showing purpura and foci of superficial erosions. Internal metastasis and death may occur within three months to two years.

Sporadic atypical mole syndrome. A report of five nonfamilial B-K mole syndrome-like cases and histopathologic findings.

We report five sporadic B-K mole syndrome-like cases. Histopathologic findings in this condition are characteristic. Clinical and pathologic diagnoses do not have to await the appearance of relatively large or malignant lesions. The dermatopathologist can alter the clinician to the occurrence of sporadic atypical mole syndrome.

Scabies: histological study of inflammatory lesions.

Histological findings of the inflammatory lesions of scabies are distinctive enough to guide the pathologist in the direction of this diagnosis. It is characterized by a combination of an acute, vesicular, eczematous type of epidermal change and an erythema multiforme type of dermal reaction. When this combination is present, a search should be made to expose the organism in tissue sections or in scrapings of the cutaneous lesions.

Hyperkeratosis of nipple and areola.

Hyperkeratosis of the nipple and areola is a rare condition that may occur in association with various forms of ichthyosis or as the result of extension of an epidermal nevus. The nevoid form is extremely rare and appears most commonly in women in their second or third decade of life. It is characterized by verrucous thickening and brownish discoloration of both nipples and areolae. Thirteen cases of this type have been reported. We are describing two additional cases to bring the total to 15 instances.

Speckled lentiginous nevus.

Speckled lentiginous nevus is, we feel, a distinctive nevocytic disorder and a clinical variety of nevus-cell nevus. The speckled areas show varying histological patterns that range from nevus incipiens to junctional and compound nevi. The background shows histological features of lentigo simplex. It is our contention that speckled lentiginous nevus should be separated from nevus spilus and nevus spilus tardus (Becker's), which we consider to be variants of epidermal nevus.

Combined adnexal tumor of the skin.

Two patients had distinctive adnexal skin tumors that showed cellular differentiation toward the formation of more than one adnexal structure. In one patient, the tumor showed differentiation toward pilar and sweat ductal structures. In the second patient, tumor differentiation toward the formation of sebaceous glands, pilar, and sweat ductal structures was found. We propose the term "combined adnexal tumor of the skin" for this neoplasm.

Staining of amyloid with cotton dyes.

We have utilized three cotton dyes, Pagoda Red, RIT Scarlet No. 5, and RIT Cardinal Red No. 9, for the microscopic demonstration of amyloid in cutaneous histopathology. All three dyes stained amyloid specifically, yielding a bright orange color. The preparation of staining solutions and the staining procedure are simple, practical, and can be applied routinely in a dermatopathology laboratory.

Eccrine adenocarcinoma. A clinicopathologic study of 35 cases.

A clinicopathologic study was made of 35 patients with primary eccrine adenocarcinoma diagnosed in the past 20 years from among 450,000 consecutive skin biopsy specimens. Histologically the following four distinct variants were identified: eccrine porocarcinoma (18 cases), syringoid eccrine carcinoma (12 cases), mucinous eccrine carcinoma (three cases), and clear cell eccrine carcinoma (two cases). Overall, eccrine adenocarcinomas are destructive lesions with a tendency to local recurrence. The syringoid histologic variant appears to be well differentiated and may have a benign clinical course; the lesion remained localized to the skin in our 12 cases. Regional lymphatic and distant metastasis, however, occurred in two patients with eccrine porocarcinoma.

Eosinophilic ulcer of the tongue.

Two cases of tongue ulcers are presented. Histopathologic examination of biopsy specimens obtained from each case showed marked submucosal and muscular infiltration of polymorphonuclear eosinophils compatible with the diagnosis of eosinophilic ulcer of the tongue. The disease entity appears to be uncommon, yet, it should be recognized as benign since in both instances, healing was spontaneous.

Chronic lupoid leishmaniasis. Evaluation by polymerase chain reaction.

BACKGROUND: The cutaneous lesions in chronic lupoid leishmaniasis resemble those of lupus vulgaris, both clinically and histologically. The differential diagnosis is difficult and may depend on the detection of a few Leishmania amastigotes in the histologic sections, the growth of the promastigotes in cultures, or the identification of amastigotes by other techniques. Polymerase chain reaction was used to detect Leishmania amastigote DNA in tissue samples obtained from 65 patients with chronic lupoid leismaniasis, and the results were confirmed by Southern blot analysis. OBSERVATIONS: The histologic findings of a predominantly epithelioid cell granuloma surrounded by lymphocytic infiltrate in chronic lupoid leishmaniasis are very similar to those observed in lupus vulgaris. Extensive histologic examination of the sections in this series revealed occasional macrophages containing a few amastigotes in only 12 cases. Cultures in NNN medium yielded Leishmania promastigotes in 20 cases. Polymerase chain reaction studies using a Leishmania-specific primer identified Leishmania DNA in 30 of 63 cases, and those using a Mycobacterium tuberculosis primer were found to be negative for mycobacteria in 47 cases tested, including 11 cases with a positive tuberculin skin reaction. CONCLUSIONS: The histologic findings in chronic lupoid leishmaniasis resemble those of lupus vulgaris. Polymerase chain reaction studies were useful in identifying amastigotes in 30 (47.6%) of 63 cases. This study confirms the presence of DNA molecules of Leishmania amastigotes in samples of formalin-fixed, paraffin-embedded granulomatous tissue obtained from patients with chronic lupoid leishmaniasis.

Detection of Borrelia burgdorferi DNA (B garinii or B afzelii) in morphea and lichen sclerosus et atrophicus tissues of German and Japanese but not of US patients.

OBJECTIVE: To elucidate the geographic and genospecific association of Borrelia with morphea and lichen sclerosus et atrophicus (LSA). DESIGN: The association of Borrelia burgdorferi with morphea and LSA has been reported, but is still controversial. We conducted a retrospective survey of Borrelia DNA in skin biopsy specimens. SETTINGS: The samples were collected from the outpatient clinic of university hospitals and a dermatopathology laboratory. PATIENTS: Skin biopsy specimens (19 morphea and 34 LSA) were obtained from patients in the United States, Japan, and Germany. DNA samples were subjected to amplification with polymerase chain reaction for B burgdorferi flagellin gene, and for the genotype-specific detection of B burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii. RESULTS: Five cases of morphea and 2 cases of LSA in Germany and Japan yielded positive signals for B garinii or B afzelii, the European species. None of the American samples were positive for Borrelia polymerase chain reaction. Borrelia burgdorferi sensu stricto was not detected in any of the specimens. CONCLUSION: Morphea and LSA in Germany and Japan can be related with European genotypes of Borrelia.

Premalignant skin lesions.

The most common precancerous skin lesions are actinic keratoses, Bowen's disease, and keratoacanthoma. Actinic keratoses appear over the exposed areas of the body as the result of actinic radiation. Bowen's disease is most probably secondary to the effects of internal carcinogens. Keratoacanthomas are self-limited lesions that occasionally may transform into invasive squamous cell carcinoma.

Pilary complex carcinoma: an adnexal carcinoma of the skin with differentiation towards the components of the pilary complex.

We report twelve cases with a distinctive form of adnexal carcinoma occurring most commonly over the head and neck of relatively old individuals. The growth was single in all cases, deep dermal in location, and consisted of massive proliferation of small basaloid cells with only occasional connection with the surface epidermis. The basaloid tumor masses showed only a few areas of palisading of their outer cell nuclei and occasional retraction space formation. The neoplasm revealed scattered areas of trichilemmal and epidermoid keratinization, foci of sebaceous, and areas of sweat ductal differentiation indicating participation of various components of the pilary complex.

Rubber-induced depigmentation secondary to a wrist splint.

Chemically induced localized skin depigmentation is not a common observation. We report a case with localized skin depigmentation secondary to the rubber tag of a wrist splint.