Paul D. Garen

Malignant rhabdoid tumor of the central nervous system

Originally described and most frequently reported in association with the kidney, the malignant rhabdoid tumor (MRT) is a highly aggressive neoplasm with distinctive morphologic features. Extrarenal sites reported for this neoplasm include the liver, thymus, and various soft tissue sites. Young infants are affected with rare exceptions. We report the case of a 3-month-old boy who presented with hyperirritability and increasing head size over several weeks. The patient died following a two-week hospital stay marked by development of seizures, paralysis, and apnea. At autopsy, significant findings were limited to the central nervous system. The subarachnoid space contained neoplasm throughout, with multiple areas of parenchymal invasion. A predominating intraparenchymal mass was present in the inferior cerebellum contiguous with the neoplasm in the subarachnoid space and probably represented the site of origin. Microscopically, the neoplasm was composed of a highly cellular monomorphic population of polygonal cells with roughly ovoid vesicular nuclei and conspicuous nucleoli. Variable amounts of cytoplasm were present, and many cells contained a single, welldemarcated eosinophilic hyaline globule adjacent to the nucleus. Ultrastructurally, the cytoplasmic globules were composed of whorled aggregates of intermediate filaments. Immunoperoxidase studies confirmed that the filaments were composed, at least in part, of vimentin. The morphologic and immunohistochemical features are diagnostic of MRT, an entity of unknown histogenesis that has not been reported previously as a primary neoplasm of the CNS.

Scleroderma Following Augmentation Mammoplasty: Report of a Case and Review of the Literature

A 46-year-old woman developed localized scleroderma after surgical manipulation of her silicone gel-filled breast prostheses. She developed firm, shiny plaques on her legs that progressed to involve the thighs. Histopathologic examination of a deep-skin biopsy specimen confirmed the diagnosis of scleroderma. On surgical removal of the silicone implants, and their replacement with saline-filled implants, the scleroderma gradually resolved. Histopathologic examination of the removed implant capsules revealed evidence of silicone leakage. All new female patients with scleroderma should be questioned and examined regarding augmentation mammoplasty. Until prospective studies are completed on the possible association between scleroderma and silicone breast implants, it would seem prudent to use the saline-filled, elastomeric envelope-type breast implant for augmentation mammoplasty rather than the silicone gel-filled implant.

Aspiration cytologic, ultrastructural, and DNA cytometric findings of solid and papillary tumor of the pancreas.

Solid and papillary epithelial neoplasm of the pancreas (SPENP) is a rare lesion characteristically occurring in young women. By contrast with pancreatic ductal adenocarcinomas, SPENP is a slow‐growing tumor that rarely metastasizes or is fatal. The current report describes light and electron microscopic and histochemical findings with DNA flow cytometric analyses of two cases of SPENP. The first patient was a 24‐year‐old woman; the second, a 72‐year‐old man. Although SPENP is rare in older men, both patients had characteristic radiographic and light microscopic features of SPENP. Ultrastructural evidence of acinar differentiation was seen in the first patient; the second patient had focal neuroendocrine differentiation. Flow cytometric analysis of the first tumor demonstrated diploid‐range DNA content with a 5.8% S‐phase fraction (SPF). The DNA cytometric analysis of a biopsy specimen from the second tumor revealed diploid‐range DNA content with a 6.1% SPF, although subsequent sampling of the resected tumor showed an aneuploid population with a DNA index of 1.8 and SPF of 2.1%.

Pyoderma gangrenosum in pediatric acquired immunodeficiency syndrome

We describe two children with human immunodeficiency virus infection in whom pyoderma gangrenosum developed. Although pyoderma gangrenosum most commonly occurs in children with inflammatory bowel disease, it has also been described in patients with a variety of immunodeficiencies. In such patients a vigorous search to exclude a treatable infection should be made before the lesions are treated as pyoderma gangrenosum.

Multiple rhabdomyomatous mesenchymal hamartomas of skin.

A case of multiple rhabdomyomatous mesenchymal hamartomas is presented. The patient is a black male infant, the product of an uncomplicated term gestation and delivery. At birth, there were numerous polyps distributed over the periorbital and periauricular areas bilaterally. Some appeared fingerlike with constrictions below their tips. Others were branched or globular in shape. These projections showed spontaneous and independent movement, particularly during feedings. On histopathologic examination, the polyps were covered by squamous epithelium and contained normal follicular units. Bundles of skeletal muscle were present in the reticular dermis, extending into the subcutis. Regular cross-striations were seen in these muscle fibers. In some specimens, the muscle bundles formed a solid, central core. Skeletal muscle histochemical stains confirmed the presence of both types 1 and 2 muscle fibers. Electron microscopy revealed a normal skeletal muscle banding pattern. This case is the first report of multiple rhabdomyomatous mesenchymal hamartomas of skin. Functional skeletal muscle with spontaneous movement is part of the clinical picture.

Oral neurofibrosarcoma associated with neurofibromatosis type I

One of the most feared complications of neurofibromatosis type I (NF-I) is development of cancer, which is estimated to occur in about 5% of cases. The most common associated malignancy is the neurofibrosarcoma (NFS). HOwever, oral NFS in association with NF-I has rarely been reported. We report two cases of oral NFS arising in patients with NF-I. Both patients died of their tumors. Oral NFS arising in association with NF-I appears to have an extremely poor prognosis, as do these tumors at other sites of the body.

D-penicillamine-induced elastosis perforans serpiginosa in a child with juvenile rheumatoid arthritis. Report of a case and review of the literature.

Elastosis perforans serpiginosa is a rare complication of D-penicillamine therapy. It has been reported to occur in Wilsons disease and cystinuria, usually after many years of high-dose therapy. We report a case of D-penicillamine-induced elastosis perforans serpiginosa with unique clinical features occurring in a 10-year-old child with juvenile rheumatoid arthritis who received only 71 gm of the drug over 9 months. The case is also unusual because of the short course and low cumulative dose of drug received and because of the calcification of elastic fibers. The calcification of elastic fibers suggests that this case may represent an unusual variant of elastosis perforans serpiginosa or an overlap with pseudoxanthoma elasticum. All reported cases of D-penicillamine-induced elastosis perforans serpiginosa are reviewed, and histopathologic and electron microscopic findings are presented. The theoretic mechanisms of action of D-penicillamine on elastic tissue synthesis and morphology are discussed.

Annular epidermolytic ichthyosis: A unique phenotype

A 30-year-old white woman developed bullous and ichthyosiform skin lesions at the age of 8 months. Blistering ceased at puberty, but the hyperkeratotic plaques persisted. She subsequently delivered five children, two of whom were affected with a bullous type of ichthyosis. At the age of 27 years, she developed numerous annular and polycyclic, erythematous, hyperkeratotic plaques on the trunk and extremities that were pruritic, enlarged slowly, and then resolved. Histopathologic examination of these annular plaques revealed epidermolytic hyperkeratosis. Electron microscopic examination of the annular plaques showed interrupted perinuclear tonofilament rings consistent with either bullous ichthyotic erythroderma of Brocq or ichthyosis bullosa of Siemens. This kindred may represent a new phenotype of epidermolytic (acanthokeratolytic) ichthyosis.

Intraparotid facial nerve neurofibroma: a case report and literature review.

A 22-year-old woman had a 4-month history of a right parotid mass. The patient noted minimal tenderness at the involved area, but was otherwise asymptomatic. There was no stigmata or family history of neurofibromatosis. Preoperative fine-needle aspiration cytology of the mass was nondiagnostic. At surgery, a 1.8 x 1 x 1.7 cm pink ovoid mass was noted to envelop the zygomatic branch of the facial nerve 1.5 cm distal to the pes anserinus. Electrical stimulation of the mass readily elicited facial movement. Removing the mass from the nerve was difficult, but the majority of zygomatic fibers were left intact.

Juvenile Xanthogranuloma of the Paravertebral Soft Tissue in Infancy: A Report of Two Cases

We report 2 cases of paravertebral soft tissue lesions with the histologic features of juvenile xanthogranuloma, both of which occurred in infants. Juvenile xanthogranuloma situated in the soft tissue is rare. We describe 2 cases with similar clinical and pathologic features; there has been no recurrence at 1 and 2 years after excision, respectively.