Toru Shoji

Eruptive melanocytic nevi after Stevens-Johnson syndrome

Widespread melanocytic nevi may rarely appear suddenly after a severe bullous disease. We describe two patients in whom eruptive melanocytic nevi developed 3 weeks after a severe episode of Stevens-Johnson syndrome. Benign melanocytic proliferation may develop after a bullous dermatosis and should not be confused with malignant or metastatic melanoma.

Two cases of Kaposi's sarcoma mimicking Stewart-Treves syndrome found to be human herpesvirus-8 positive.

Although angiosarcoma is the most frequent tumor arising in the clinical setting of chronic lymphedema, as in Stewart-Treves syndrome, Kaposis sarcoma has also been reported in this setting, although rarely. We describe two women who developed Kaposis sarcoma in the lymphedematous arm many years after surgery for breast cancer. Case 1 is a 92-year-old and Case 2 is an 81-year-old; they underwent left total mastectomy and axillary node dissection for infiltrating breast carcinoma in 1981 and 1982 respectively. At that time, neither patient received further treatment. Except for persistent lymphedema, both women did well until over fourteen years later when each noted the development of several purple asymptomatic plaques on the edematous arm. In both, the clinical diagnosis at the time of biopsy was angiosarcoma. However, histologic findings in both cases were typical for Kaposis sarcoma. In addition, a nested polymerase chain reaction (PCR) for the detection of a 233bp segment of KSHV/HHV8 was performed on DNA extracted from the paraffin-embedded specimens and both cases were positive for this sequence. Histologic sections of both cases were also tested for KSHV by in situ hybridization and demonstrated a positive signal in the lesional cells in each case.

Basal cell carcinoma with massive ossification.

We report a case of basal cell carcinoma with massive ossification in a 66-year-old white man. Ossification in various benign and malignant neoplasms have been reported including basal cell carcinomas, in which ossifications are seen in small foci or peripheral rim of the tumor. However, in our case, massive ossification is seen throughout the tumor, and only small areas of the periphery of the tumor show diagnostic histology. Therefore, this case might have presented a diagnostic difficulty or been misdiagnosed as an osteoma cutis if a smaller incisional or punch biopsy had been performed. The phenomenon of bone formation itself is not specific for any diagnostic entity, and therefore an underlying lesion should be carefully sought in case of secondary ossification.

Benign sebaceous neoplasm with prominent epidermal component.

A 65-year-old woman presented with a solitary nodule within an erythematous plaque in her right groin. Histopathologic examination showed central lobular proliferation of basaloid cells admixed with mature sebaceous cells and a lateral extensive intraepidermal component composed mostly of lobules of mature sebocytes consistent with intraepidermal epithelioma with sebaceous differentiation and focal invasion. Although various cutaneous neoplasms may show an intraepidermal growth pattern, extensive sebaceous differentiation in such a neoplasm, as seen in this case, has not been described. Electron-microscopic study revealed that the basaloid cells have features of pluripotential cells. This observation supports the previously reported concept that intraepidermal epithelioma may be composed of a group of heterogeneous tumors with various degrees and lines of differentiation. Additionally, sebaceous epithelioma/adenoma should be considered in the differential diagnosis of the cutaneous neoplasms with an intraepidermal growth pattern.

Multiple pigmented basal cell carcinomas

Basal cell carcinoma is the most common of all skin cancers and the most prevalent one among Caucasians. Rarely, these tumors are seen in other races. We report a 77-year-old Korean woman who presented with multiple darkly pigmented enlarging nodules on her scalp, face, trunk, and extremities. The patient had first noted a 6-mm pigmented lesion on her left eyebrow 10 years previously. Since then, other lesions had appeared in many locations on her body. She had been otherwise healthy and without a history of exposure to arsenic or radiation. There was no family history of skin cancer, xeroderma pigmentosum, or basal cell nevus syndrome. On physical examination, multiple darkly pigmented dome-shaped papules and nodules were present on her scalp, face, right forearm, lower abdomen, and inguinal areas. They ranged in size from 0.5 mm to 2 cm. The larger ones showed central ulceration. Multiple biopsy specimens from different sites showed pigmented basal cell carcinomas. Clinically, there was no evidence of nevus sebaceus, xeroderma pigmentosum, basal cell nevus syndrome, or immunodeficiency. Clinical workup including chest radiography, abdominal ultrasound, bone scan, and brain computerized axial tomography scan did not demonstrate primary or secondary tumors. The results of serologic and hematologic tests were also within normal limits. This is an unusual case report of multiple pigmented basal cell carcinomas in an Asian woman without any predisposing risk factors.