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Notes: Although benign epithelioid peripheral nerve sheath tumors have been described, they are rare, and benign epithelioid schwannomas have not yet been established as a specific histologic variant.We present four cases of tumors which we believe would meet criteria to be classified as benign epithelioid schwannomas. Biopsy specimens obtained from four different patients were examined with routine and immunohistochemical staining. All the tumors were well-circumscribed lesions that were surrounded by a capsule containing EMA-positive cells. The cellular component was composed of epithelioid cells, in which there was a lack of mitotic activity. Immunohistochemical studies showed the tumor cells were S-100 protein and Leu 7 positive and HMB-45 negative. In addition, type IV collagen encircled individual cells within the tumor, indicating a continuous basal lamina. We report a group of cutaneous epithelioid schwannomas. Although the presence of such tumors is not unexpected, this diagnosis may not be initially considered because of this rare cytoiogic feature.

Notes: A 29–year-old black vi/oman presented with a 6–year history of lupus nephritis, cerebritis, arthritis, and recurrent facial erythema. She was admitted to the National Naval Medical Center following an acute lupus flare manifested by the onset of acute tubular necrosis requiring the initiation of hemodialysis. The patient had also developed a Staphylococcus aureus septicemia secondary to an infected IV site. During the first and second weeks in hospital, the patient responded well to aggressive antibiotic therapy and oral prednlsone. As the oral prednisone was decreased from 60 mg to 40 mg per day on day 19 in hospital, the patient developed several tender, erythemafous, subcutaneous nodules over the lower extremities (Fig. 1). There was no cutaneous ulceration or drainage. Although the initial clinical diagnosis was erythema nodosum, a deep incisional biopsy was performed to rule out infectious, vasculitic, or lupus panniculitis.Histologic findings of a representative leg nodule included lobular panniculitis with extensive fat necrosis,' ghost cell' formation, acute suppurative inflammation, and focal calcification (Fig. 2). Stains and cultures for organisms were negative. These findings were felt to be pathognomonic for nodular fat necrosis associated with pancreatic disease.Laboratory data revealed serum amylase and lipase to be markedly elevated at 1342 U/L (A/=28–110 U/L) and 4160 U/L (W=7–60 U/L), respectively; white blood cell count and differential were within normal limits. Other significant laboratory data included an anti-DNA of 692 lU/mL (A/=〈100 IU/mL) and positive anti-Sjogren's syndrome-A.Simultaneous punch biopsy of an erythematous facial macule revealed epidermal atrophy, vacuolar interface change, and a mild perivascular and periadnexal lymphohistiocytic infiltrate, consistent with lupus erythematosus. Computed tomography (CT) scan and ultrasound exannination of the abdominal cavity failed to provide further evidence of pancreatitis.Although the patient was initially asymptomatic, 1 week following the onset of her leg nodules she developed severe ankle and knee arthralgias, abdominal pain, nausea, and vomiting which were attributed to her pancreatitis. She was treated with high-dose prednisone and Cytoxan for control of her lupus flare, which brought about the resolution of her leg nodules and associated symptoms over the following 6 weeks. Only post-inflammatory hyperpigmentation remained in the skin overlying the sites of nodular fat necrosis.