Saiichi Kon

Multiple Basaloid Cell Hamartoma with Alopecia and Autoimmune Disease (Systemic Lupus Erythematosus)

We report a 22‐year‐old Japanese woman with multiple basaloid cell hamartoma with alopecia and autoimmune disease (systemic lupus erythematosus). She presented with infiltrated large annular, brown‐violet, erythematous plaques with atrophic areas in the center on her right cheek, left abdomen and left knee. She also had progressive multiple follicular keratotic papules on her scalp, face, neck, and both axilla and hair loss from her scalp, eyebrow, and axilla. Serologically, reumatoid factor (+++), rheumatoid arthritis hemagglutination test (x1280), and anti‐nuclear antigen (x160) were positive. Histological findings of the annular lesion showed liquefaction degeneration of basal cells, lymphocytic infiltration around hair follicles and capillaries, and panniculitis with lymphoid cell infiltration, which was diagnosed as lupus erythematosus profundus. The histological findings of multiple follicular papular lesions of the scalp and neck showed aggregations of basaloid cells, partially with hair‐bulb‐like structures, which was diagnosed as trichoepithelioma. Taken together, the histogenesis of multiple basaloid cell hamartoma is thought to share the same basis with autoimmune disease.

Detection of numerical chromosomal aberrations in malignant melanomas using fluorescence in situ hybridization

To evaluate the numerical chromosomal aberration i malignant melanoma, we have applied fluorescence in situ hybridization (FISH) with repetitive DNA probes specific for chromosomes 1, 6, 7, 9, 10, and 17 on 24 fresh malignant melanomas (primary: 14, metastatic: 8).

Immunohistochemical detection of Ki-67 in epithelial skin tumors in formalin-fixed paraffin-embedded tissue sections using a new monoclonal antibody (MIB-1).

The expression of the Ki‐67 antigen was investigated in 44 epithelial skin tumors using an immunohistochemical technique on formalin‐fixed, paraffin‐embedded tissue sections. Microwave oven heating was employed for retrieval of the antigen in these tissue sections.

Trichoblastoma with Rippled‐Pattern

The following is a case study of a 36‐year‐old Japanese man with a trichoblastoma which exhibited a rippled‐pattern on the left temporal region of the scalp. The histological findings of the tumor revealed lobular aggregations composed of immature follicular basaloid cells, lobules of squamous eddy‐like foci of incomplete keratinization or small keratinous cysts, and multiple papillary mesenchymal bodies similar to hair germ. Interestingly, a rippled‐pattern of basaloid cells and hyalinized matrixes resembling the Verocay bodies of neurilemmoma was also observed. We propose that the rippled‐pattern of the basaloid cells and hyalinized matrices is caused by the characteristic stromal induction of trichoblastoma.

Interphase cytogenetics of melanocytic neoplasms: numerical aberrations of chromosomes can be detected in interphase nuclei using centromeric DNA probes

This study shows that fluorescence in situ hybridization (FISH) to thin sections cut from paraffin‐embedded material can lie used to distinguish between groups of melanocytic neoplasms and thus may be useful as an investigational and diagnostic tool. FISH with a probe for a repealed, alpha satellite sequence specific to chromosome 17 was used to investigate the chromosomal composition of dysplastic (or Clarks nevus) and Spitzs nevi and malignant melanomas. Hybridization was to thin (∼6 μm) sections cut from paraffin blocks. The number of signals per nucleus in normal diploid cells is expected to be less than 2 since the sections are thinner than one nuclear diameter. Keratinocytes and lymphocytes m these same sections showed 1–2 signals per nucleus with a mean of 1.2. Dysplastic nevi showed 1–4 hybridization signals per nucleus with a mean of 1.5. Spitzs nevi showed 1–2 signals per nucleus with a mean of 1.3. Melanomas showed 1–6 signals per nucleus with a mean of 2.1. We were thus able to use FISH to demonstrate differences in chromosome numbers between groups of benign and malignant melanocytic neoplasms. Technical improvements in the near future can be expected lo result in more precise estimates of chromosomal number.

Two Cases of Basal Cell Carcinoma Arising in Seborrheic Keratosis

The present study reports two cases of basal cell carcinoma arising in seborrheic keratosis. The first case is a seventy‐three‐year‐old female who presented with a blackish nodule arising from a pigmented lesion on her chest. Histopathological analysis of the nodule and the pigmented lesion revealed a basal cell carcinoma with hair follicular differentiation and an acanthotic seborrheic keratosis, respectively. The second case is a seventy‐year‐old female with a blackish nodule arising from a pigmented lesion on her back. Histological analysis of the nodule revealed an atypical basaloid cell mass surrounded by a seborrheic keratosis lesion. In addition to the coexisting seborrheic keratosis with the basal cell carcinoma, a basaloid follicular hamartoma that showed muliple hamartomatous hair follicles or small cysts replaced by a branching cord or lace‐like network of basaloid cells surrounded by fibrovascular stroma was identified. We concluded that both cases presented a rare combination of a seborrheic keratosis which underwent a malignant change to basal cell carcinoma. It appears that both basal cell carcinomas and seborrheic keratosis may derive from a similar source: pluripotential cells of either the epidermis or hair follicle epithelium.

Multiple Agminated Juvenile Melanoma Arising on a Hyperpigmented Macule

A case of multiple agminated juvenile melanoma (MAJM) arising on a hyperpigmented macule is reported. The patient, a 1‐year‐old boy, had 9 small nodules on an irregular, hyperpigmented macule on the right shoulder. Histologically, the nodules contained nests of spindle‐shaped cells in their epidermis and at the dermoepidermal junction, and the hyperpigmented macule exhibited increased melanin granules in the basal layer and small nests of epithelioid cells. We concluded that MAJM on a hyperpigmented macule is the subtype of the nevus spilus.

A Case of Pigmented Dermatofibrosarcoma Protuberans (Bednar Tumor)

The present paper reports a 67‐year‐old male with pigmented dermatofibrosarcoma protuberans (Bednar tumor) on his right shoulder. The lesion had recurred twice. Clinically, the lesion was a reddish‐brown, exophytic, multilobular, firm nodule with an irregular surface, which measured 6.4 times 4.2 cm. Histologically, the proliferated fibroblasts showed a cartwheel pattern and stained positively with CD34, similar to those of a common dermatofibrosarcoma protuberance. However, many melanin‐bearing cells that were positive for the S‐100 protein were found intermingled among the tumor cells.

Immunohistochemical detection of p21WAF1/CIP1 and p53 proteins in formalin-fixed paraffin-embedded tissue sections of squamous cell carcinoma of the skin

Thirty-two cases of squamous cell carcinoma (SCC) of the skin were investigated as to the expression of p53 and p21 (WAF1/CIP1) using an immunohistochemical method. These cases were surgically resected or biopsied, tissue samples were then fixed in formalin and embedded in paraffin in the conventional way. Microwave heating was used for antigen retrieval. The primary monoclonal anti-p21 antibody and the monoclonal antibody against p53 were employed. The labeled-streptoavidin-biotin-peroxidase method was used for immunohistochemical staining. Of these, 30 cases showed overexpression of p53 staining, but normal epidermal cells were free of stain. p21 positive cells were detected faintly in the middle layer cells of normal epidermis. Of these, 30 cases showed overexpression of p21 staining. The staining pattern of p53 and p21 showed intratumoral heterogeneity in SCC. In general, there was the inverse relationship between p21 and p53 staining in tumors, namely p53 positive cells were p21 negative and vice versa. However, some of the tumor cells expressed both genes simultaneously. This study supports a hypothesis that p21 expression is regulated by p53, and that it is also regulated by an additional pathway(s) in SCC.

A Case of Superficial Epithelioma with Sebaceous Differentiation

Superficial epithelioma with sebaceous differentiation developed on the left cheek of a 58‐year‐old man over a three‐year period. Biopsy of the lesion demonstrated plate‐like lobules of basophilic basaloid cells with broad attachments to the overlying epidermis. Clusters of or solitary sebaceous cells were present within the lobules. Three tumor types were considered; a subtype of sebaceoma growing in the epidermis, an acanthotic seborrheic keratosis subtype with sebaceous differentiation, or a tumor of the follicular infundibulum with sebaceous differentiation.