Giant cell angiofibroma of the orbit and eyelid.

PURPOSE: To report the clinicopathologic features of a newly recognized tumor, giant cell angiofibroma. DESIGN: Observational case series. MAIN OUTCOME MEASURES: Clinical and histopathologic features of giant cell angiofibroma. METHODS: Light and electron microscopy and immunohistochemistry of five cases of giant cell angiofibroma. RESULTS: A total of five patients (4 women and 1 man) are described: two presented with a painless mass in the eyelid, two with a mass in the orbit, and one presented with a conjunctival lesion. All lesions were well demarcated with no capsule and were composed of blood vessels, a patternless spindle-shaped cell proliferation with a solid and pseudovascular appearance, and multinucleated giant cells. Both spindle-shaped and giant tumor cells were intensely positive for CD34 and vimentin. CONCLUSION: Giant cell angiofibroma resembles solitary fibrous tumor and giant cell fibroblastoma and should be considered in the differential diagnosis of spindle-cell tumors in the eyelid, orbit, and conjunctiva.

Deletion of PTEN in a patient with Bannayan-Riley-Ruvalcaba syndrome suggests allelism with Cowden disease.

We report on an 18-month-old boy with an interstitial deletion at 10q23.2-q24.1. This region includes the PTEN gene, mutations of which have been reported to cause Cowden disease. Our patient presented with manifestations of Bannayan-Riley-Ruvalcaba (BRR) syndrome. The BRR syndrome is a rare disorder which presents most commonly in childhood. Cowden disease is a disease of adulthood and is inadequately described in children. Because of the considerable phenotypic overlap between the two disorders, and the cytogenetic and molecular findings in our patient, we suggest that BRR syndrome and Cowden disease are allelic.

Nitric oxide metabolism in wounds.

Arginine can be metabolized in wounds to nitric oxide and citrulline by nitric oxide synthase or to urea and ornithine by arginase. We investigated the expression of these arginine metabolic pathways over a 3-week period. Groups of 8-10 male Balb/C mice underwent a dorsal skin incision and subcutaneous polyvinyl alcohol sponge implantation. The animals were sacrificed at various times, and sponges were harvested to obtain wound fluid and wound cells. Cells or whole sponges were incubated with L-[2,3-(3)H]arginine, with or without N(G)-L-monomethyl-arginine (NMMA, a competitive inhibitor of nitric oxide synthase). Nitrite and nitrate (both stable end products of nitric oxide metabolism) and amino acids were measured in wound fluid and wound cell culture supernatants. Increasing concentrations of nitrite and nitrate were noted in wound fluid and in whole sponge cultures until the second week postwounding, indicating sustained wound nitric oxide synthesis. In wound fluid arginine levels were undetectable at all times, suggesting sustained utilization. Wound fluid citrulline levels showed an early peak and then a gradual decrease, suggesting that recycling for continued nitric oxide production may occur. Wound fluid ornithine levels increased until Day 10 and remained elevated, indicative of continued arginase activity. In vitro production of nitrite/nitrate and citrulline by cells and whole sponges was inhibitable by NMMA. Inducible nitric oxide synthase expression was confirmed by immunoblotting, while immunohistochemistry demonstrated that macrophages are a major source of wound nitric oxide. The data show that nitric oxide synthesis occurs for prolonged periods after injury and macrophages appear to be a major cellular source.

Flow cytometric DNA analysis of primary and concurrent metastatic squamous cell carcinoma of the head and neck.

Adequate flow cytometric DNA analysis comparing primary and concurrent metastatic squamous cell carcinoma of the head and neck has not been done in the past. The purpose of this study was to define any differences between the primary and concurrent metastasis of each patient with respect to flow cytometric parameters and histologic grade. Paraffin-embedded archival specimens from 28 patients with primary and metastatic tumors were prepared into nuclei and analyzed by flow cytometry using human lymphocyte standards. The mean DNA index was 0.82 for primary tumors and 0.83 for the metastases. Aneuploidy was found in 68 percent of primary tumors and in 82 percent of metastases. The percentage of cells in the proliferative fraction was 40.4 in the primary tumors and 24.5 in the metastases. A direct correlation was found between the differentiation of the primary and metastatic tumors. No survival difference was discovered among the flow cytometric parameters and histologic grade. We conclude that there is no difference between the primary and concurrent metastasis in squamous cell carcinoma of the head and neck with regard to DNA index, aneuploidy, or histologic grade.