Tumoral calcinosis: a case report with an electron microscopic study.

A 68-year-old woman developed large subcutaneous masses on her abdomen and thighs after a bruise sustained in a traffic accident. She had severe pain when sitting up straight. Histological examination revealed calcified tissues in the entire dermis of the injured areas. On electron microscopy, crystalline materials were observed in the dermis, which seemed to be formed by the deposition of hydroxyapatite on unusual proteoglycan. In a vessel wall, a thick, layered basement membrane was observed. This suggests that vascular injury and subsequent hypoxia play a role in the process of calcinosis. We performed a partial resection with good results in alleviating the patient's pain.

Pachyonychia congenita associated with steatocystoma multiplex.

We present an unique case of pachyonychia congenita associated with steatocystoma multiplex. A 33-year-old Japanese man had thickening and gray-brown dicoloration of all nails and a large number of nodules or tumors over his entire skin. No palmar and plantar hyperkeratosis, leukokeratosis of the mucous membranes, or follicular keratosis were observed. Histology of these tumors revealed the typical features of steatocystoma multiplex.

An important role of tumor necrosis factor-alpha in the induction of adhesion molecules in psoriasis.

Recent studies have suggested that cell adhesion plays an important role in the development and regulation of inflammation. To elucidate the mechanisms of regulation of adhesion molecule expression by cytokines in psoriatic lesions, we compared the expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and P-selectin immunohistochemically in involved and uninvolved psoriatic skin with the expression of these molecules in normal skin, and measured the amounts of tumor necrosis factor-alpha, interferon-gamma, interleukin-1alpha, and interleukin-1beta in the supernatant of freeze-thawed skin specimens using an enzyme-linked immunosorbent assay. There was strong staining for P-selectin on endothelial cells from involved skin. There was also strong staining for intercellular adhesion molecule-1 on keratinocytes, dermal infiltrates, and endothelial cells from involved skin and on endothelial cells from uninvolved skin, and strong staining for vascular cell adhesion molecule-1 on dermal dendritic cells and fibroblasts and for E-selectin on endothelial cells from involved skin. Large amounts of tumor necrosis factor-alpha were detected in six out of ten specimens of involved skin, but not in uninvolved or normal skin, although interferon-gamma was detected in both involved and uninvolved skin to the same extent. Neither interleukin-1alpha nor interleukin-1beta was detected in involved skin. There was strong staining for tumor necrosis factor-alpha on keratinocytes and endothelial cells from involved skin. These findings suggest that tumor necrosis factor-alpha might play an important role in the induction of vascular adhesion molecules in psoriatic lesions.

Atypical melanosis of the foot.

We present a case of a seemingly malignant pigmented lesion on the foot, arising in a Japanese female. Clinically, the lesion was characterized by irregular borders and variegated pigmentation closely mimicking those of acral lentiginous melanoma in situ. However, the histologic findings revealed only focal, slight, melanocytic hyperplasia with minimal cytologic atypia along the basal layer. Despite the malignant clinical features, thorough histologic examination failed to disclose any area with significant melanocytic atypia or evidence of malignancy. To the best of our knowledge, no similar lesions with the clinical appearance of melanoma in situ and completely lacking histologic evidence of malignancy have been reported. We, therefore, prefer to designate this lesion as atypical melanosis of the foot, to highlight the clinically atypical findings and to distinguish this from malignant melanoma in situ of the foot (1).

Acral lentiginous melanoma (including in situ melanoma) arising in association with naevocellular naevi.

Acral lentiginous melanoma (ALM) occurring on the sole of the foot is the most common type of malignant melanoma in Asians, African and North American Blacks, but is relatively infrequent in Caucasians. According to the literature ALM is thought less likely to arise in a precursor naevus of any type or be associated with dysplastic naevi elsewhere on the skin. We present five cases of ALM (two invasive and three in situ cases) arising in association with pre-existing naevi on the foot in Asians and Caucasians. All patients were female, aged 35-66 years (mean = 47.8). Clinically, all five tumours demonstrated various shades of tan, brown and black, admixed with hypopigmented areas. Histologically, these melanomas showed a lentiginous character of the radial growth phase component with rare foci of pagetoid intra-epidermal spread. Invasive determal components in the form of epithelial and spindle cells were evident in two cases, with a measured depth of 1.7 and 0.85 mm, respectively. Pre-existing naevi, either dermal or junctional, were identified in all tumours. Clinical follow-up in all patients showed no evidence of recurrence or metastasis over a period of 4 months-5 years. These cases appear at variance with the general belief that ALM and ALM in situ arise de novo and rarely arise in precursor naevi. To the best of our knowledge, this is the first documented series of ALM in situ arising in association with pre-existing naevi. We conclude that ALM can arise in association with acral naevi.

Dermatofibrosarcoma protuberans of the sole.

A 42-year-old Chinese man presented with a dome-shaped, red, tender, bony-hard tumor on his right sole. Histological examination revealed tumor nests which consisted mainly of fibroblast-like cells with large, spindle-shaped nuclei and histiocyte-like cells extending from the upper dermis to the subcutaneous tissue. The tumor cells showed both a storiform and a cartwheel pattern. The location of a dermatofibrosarcoma protuberans on the plantar aspect of the foot is exceptional.

Basal cell carcinoma with eccrine differentiation.

We describe a light, electron microscopic, and immunohistochemical study of basal cell carcinoma with eccrine differentiation. The cytoplasm did not stain with fat stain on cryostat sections, but contained numerous gland-like structures. Immunohistochemistry on formalin fixed, paraffin embedded tissues using antibodies to human involucrin, thirteen kinds of cytokeratin, S-100 protein, and carcinoembryonic antigen (CEA) was performed. We found that tumor cells were positive for keratin, PKK1, MA-903, No 8, No 19, AE 1, AE 3, and 5 + 8. Tumor cells were negative for S-100 protein, CEA, and the other antigens examined. Electron microscopy demonstrated short microvilli and amorphous materials within the intracytoplasmic cavity. We concluded that this tumor is basal cell carcinoma with eccrine differentiation.

Detection of inflammatory cytokines in psoriatic skin.

Recent investigations have revealed the involvement of cytokines in the pathogenesis of psoriasis. This study examined the amount of inflammatory cytokines--interleukin-1 (IL-1), interleukin-6 (IL-6) and granulocyte macrophage colony-stimulating factor (GM-CSF)--released into the supernatants of organ cultures of involved and uninvolved skin from psoriatic patients and normal skin from healthy individuals. Bioassays were employed to detect the activities of IL-1 and IL-6. Enzyme-linked immunosorbent assay (ELISA) methods were used to quantitate immunoreactive IL-1 alpha, IL-1 beta, IL-6 and GM-CSF. The activity of IL-1 in uninvolved psoriatic skin was found to be increased relative to that in involved and normal skin, while immunoreactive IL-1 beta was found only in involved skin. A neutralization experiment showed that bioactive IL-1 was mostly attributable to IL-1 alpha. Uninvolved psoriatic skin also secreted higher amounts of both bioactive and immunoreactive IL-6 compared with involved skin. Immunoreactive GM-CSF was detected in uninvolved skin only. These cytokines detected in uninvolved skin may have been released from epidermal or mesenchymal cells, since uninvolved skin contained fewer inflammatory infiltrates. Our results offer additional evidence that increased amounts of inflammatory cytokines in uninvolved skin may provide a preliminary condition and play important roles in the initial events in the evolution of psoriatic lesions.

Milium-like syringoma in the perianal region.

We report a case of syringoma clinically presenting as milia in the perianal region. Milium-like syringoma is an unusual clinical variant of the tumor, and this is, to our knowledge, the first reported case occurring perianally.

A case of giant cell tumor of the tendon sheath developing on the palm.

A 22-year-old Japanese woman with a giant cell tumor of the tendon sheath on the palm is described. The location of the tumor is rare. Light microscopically, the tumor consisted of round or polygonal cells, giant cells, and foam cells. Electron microscopically, histiocyte-like cells and fibroblast-like cells were mainly observed, suggesting that the tumor may have originated from the synovial membrane.

Pedunculated lipofibroma. A clinicopathologic study of thirty-two cases supporting a simplified nomenclature.

Thirty-two cases are described of a relatively rare form of benign connective tissue proliferation characterized by ectopic fatty tissue in the dermis. The lesions usually appear as large, solitary, slow-growing, pedunculated to dome-shaped, skin-colored nodules or plaques showing predilection for the buttock and upper thigh. Other areas involved include the back, shoulder, knee, neck, and ear. Twenty patients were women and 12 were men, 19 to 78 years of age (mean, 46.9 years). The size of the lesions ranged from 4 to 69 mm (mean, 49 mm). Histologically, the lesions were characterized by the presence of mature adipose tissue infiltrating around the periadnexal adventitial dermis and between adnexal structures and admixing with dense stromal collagen. Marked deposition of mucopolysaccharides was noted in the majority of the lesions. Clinical follow-up in all 32 patients showed no evidence of recurrence. Because of their distinctive clinicopathologic features, we prefer to designate these lesions as solitary, pedunculated lipofibroma. In addition, seven of the patients had diabetes mellitus, suggesting a possible relation between the two conditions.

Atypical melanosis of the foot. A report of three cases in Japanese populations.

BACKGROUND: Acral lentiginous melanoma is the most common type of malignant melanoma in the Japanese population. In most instances, classic acral lentiginous melanoma or acral lentiginous melanoma in situ can be readily distinguished from other benign pigmented lesions by virtue of its atypical clinical appearance. OBSERVATION: We present three cases of seemingly malignant pigmented lesions on the foot, all arising in Japanese females. Clinically, the lesions are characterized by irregular borders and variegated pigmentation closely mimicking those of acral lentiginous melanoma in situ. However, the histologic findings revealed only focal slight melanocytic hyperplasia with minimal cytologic atypia along the basal layer. Despite the malignant clinical features, thorough histologic examination failed to disclose any area with significant melanocytic atypia or evidence of malignancy. CONCLUSIONS: To the best of our knowledge, similar lesions with the clinical appearance of melanoma in situ and completely lacking histologic evidence of malignancy have not been reported. We, therefore, prefer to designate these lesions as atypical melanosis of the foot to highlight the clinically apparent atypical findings and to distinguish them from malignant melanoma in situ of the foot.

Clear cell eccrine carcinomas of the skin. A clinicopathologic study of nine patients.

BACKGROUND: Sweat gland carcinomas with clear cell features are extremely rare neoplasms, with few well documented cases reported in the literature. METHODS: Data on nine patients with malignant eccrine adnexal neoplasms characterized by a prominent clear cell neoplastic component were studied. Immunohistochemical stains with a panel of antibodies against epithelial, stromal, and neural antigens were performed on five tumors and electron microscopic examination of one. RESULTS: The tumors showed a spectrum of histologic features and growth patterns that ranged from well differentiated, low grade malignant neoplasms to poorly differentiated, highly aggressive, recurrent, and metastasizing tumors. All tumors contained a varied proportion of cells with abundant clear cytoplasm, similar to those seen in a group of benign eccrine adnexal neoplasms that have been variously designated as clear cell hidradenoma, nodular hidradenoma, clear cell myoepithelioma, and eccrine acrospiroma. Immunohistochemical stains on five tumors and ultrastructural examination in one were consistent with eccrine differentiation. Clinical follow-up of eight patients showed local recurrence in six, followed by metastases in three, despite local excision, radiation, and chemotherapy. Criteria for differentiating these tumors from their benign counterparts and from other types of malignant adnexal neoplasms and metastatic lesions are presented. CONCLUSIONS: The findings indicate that clear cell eccrine carcinomas comprise a heterogeneous group of lesions that may range from locally recurring, low grade well differentiated tumors to highly aggressive, high grade tumors with a definite potential for uncontrollable local recurrence and metastasis. Wide surgical excision is recommended as the primary treatment for such neoplasms.