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W L White

Publications and source records attributed to W L White.

At least 73 records · Page 4Linked to original sources
PubMed1996

Magnetic resonance imaging versus bone scan for assessment of vascularization of the hydroxyapatite orbital implant.

We prospectively studied 10 patients who were status postenucleation and primary placement of the hydroxyapatite orbital implant. Both the technetium-99m bone scan and gadolinium-enhanced magnetic resonance images (MRI) were obtained on the same day at variable time points in the postoperative period in order to assess the degree of vascularization. Up to 78% of the bone scans were interpreted as being completely vascularized, while only 10% of the corresponding MRI scans were consistent with complete vascularization. Cost analysis showed that MRI was cost-effective imaging modality. We conclude that contrast-enhanced MRI provides a more accurate assessment of vascularization of the hydroxyapatite orbital implant when compared to bone scan.

Adolescent↗
PubMed1996

Nitric oxide synthase activity is up-regulated in melanoma cell lines: a potential mechanism for metastases formation.

Nitric oxide (NO) may be an important mediator of tumour angiogenesis and metastasis formation. Tumour cell derived NO may be important in the regulation of angiogenesis and vasodilatation of the blood vessels surrounding a tumour. The aims of the present study were, firstly, to determine whether malignant melanoma cells and normal melanocytes had nitric oxide synthase (NOS) activity (measured by the conversion of L-arginine to L-citrulline) and, secondly, to determine whether there was a difference in NOS activity between malignant and normal cell types. This paper assays NOS activity directly in lysates from normal human melanocyte and malignant melanoma cell lines. The enzyme activity was not inducible with bacterial lipopolysaccharide and could be heat denatured. The activity of NOS was demonstrated to be both NADPH- and calcium-dependent and it was inhibitable in a dose-dependent manner by the NOS inhibitor Nw-nitro-L-arginine methyl ester. We conclude that melanoma and melanocyte cells express a constitutive form of NOS. Finally, nitric oxide synthase activity in melanoma cell lines was found to be significantly greater than in normal melanocytes. These findings suggest that NO synthesis is elevated in malignant melanoma. An elevated NO concentration in melanoma is expected to promote metastases by maintaining a vasodilator tone in the blood vessels in and around the melanoma.

Cells, Cultured↗
PubMed1996

Extra-acral calcifying aponeurotic fibroma: a distinctive case with 23-year follow-up.

Calcifying aponeurotic fibroma (CAF) is an unusual but well-characterized soft tissue neoplasm that typically involves the digits of children and frequently recurs locally. This report describes a case from the subcutis of the lumbosacral region. A 26-year-old man initially presented at age 3 and developed three recurrences over a 23-year period each at approximately 8-year intervals (ages 10, 18, and 26). The microscopic findings in all recurrences showed a lobulated, poorly circumscribed proliferation of dense fibrous tissue containing epithelioid-like fibroblasts, multinucleated cells, and islands of metaplastic chondroid differentiation with focal calcification. Despite origin from an unusual anatomic site, this case reported herein demonstrates the classical morphologic features and clinical history of CAF which showed little in the way of morphologic evolution despite 23 years of persistence. The clinical and histologic features helpful in distinguishing CAF from infantile fibromatosis and soft tissue chondroma are discussed.

Adult↗
PubMed1995

Mucocutaneous criteria for the diagnosis of Behçet's disease: an analysis of clinicopathologic data from multiple international centers.

BACKGROUND: Although four of five of the new international criteria for the diagnosis of Behçet's disease relate to mucocutaneous lesions, disagreement exists as to the exact nature of cutaneous lesions (e.g., vessel-based vs follicular). OBJECTIVE: Our purpose was to review clinical data, clinical photographs, and skin biopsy specimens from multiple medical centers throughout the world to monitor current practice in the implementation of mucocutaneous diagnostic criteria for Behçet's disease. METHODS: Ten medical centers responded to a request to collaborate by sending clinical data, photographs of cutaneous lesions, and biopsy specimens from 22 patients. RESULTS: Of specimens from 22 patients, 14 revealed a histopathologic pattern of neutrophils containing perivascular and interstitial inflammation, whereas specimens from three patients revealed only mononuclear cells in a vessel-based pattern. Biopsy specimens from three patients revealed primarily folliculocentric inflammation and an additional two specimens were from erythema nodosum-like lesions. CONCLUSION: Perivascular inflammation was the predominant histopathologic finding in specimens of cutaneous lesions in this clinical series. Folliculocentric lesions could not be predicted on the basis of review of clinical photographs. Histopathologic assessment of cutaneous lesions is crucial if the proposal is accepted that exclusion of folliculocentric lesions is important to ensure accurate implementation of diagnostic criteria in patients with suspected Behçet's disease.

Adult↗
PubMed1995

Ocular adnexal lymphoma. A clinicopathologic study with identification of lymphomas of mucosa-associated lymphoid tissue type.

PURPOSE: Extranodal marginal zone B-cell lymphoma (low-grade B-cell lymphoma of mucosa-associated lymphoid tissue [MALT] type) is a distinctive type of lymphoma that usually arises in association with mucosa or other epithelial structures and has an indolent clinical course. The frequency and clinical features of MALT lymphomas in the ocular adnexa have not been well studied. METHODS: The authors examined the clinicopathologic features of ocular adnexal lymphoma, identified a subset of cases with MALT characteristics, and determined patient outcome. RESULTS: The 42 patients, 16 men and 26 women age 35-89 years (mean, 64) were followed an average of 4.8 years. Thirty-two patients had ocular adnexal involvement at presentation (primary ocular adnexal lymphoma) and 10 had a history of lymphoma that relapsed in the orbit (secondary ocular adnexal lymphoma). In the primary group, 23 patients had lymphoma confined to the ocular adnexa, 3 had a single lesion that invaded adjacent structures, and 6 had distant spread at the time of presentation. Twenty-five patients achieved a complete remission. Nine patients, including 6 patients whose disease was localized initially, had progression or relapse of disease in distant sites. At last follow-up, 21 patients were free of disease, 9 were alive with disease and 2 had died of lymphoma. In the secondary group, at last follow-up, 1 patient had died of other causes, free of lymphoma, 3 patients were alive with disease and 5 had died of lymphoma (outcome not known in 1 case). Using the recently described revised European-American lymphoma classification, we found 16 MALT lymphomas, 8 diffuse large B cell, 12 follicular center, 3 mantle cell, 1 B-small lymphocytic lymphoma, and 2 unclassifiable low-grade lymphomas. The most common type of primary lymphoma was MALT type (15 of 30 classifiable cases), and the most common secondary lymphoma was follicular center (6 of 10). No increased frequency of conjunctival or lacrimal gland involvement by MALT lymphomas was found. All 33 lymphomas with immunophenotyping were of B lineage. CONCLUSIONS: Ocular adnexal lymphomas are B-cell tumors that develop in older adults, predominantly among women. Primary orbital lymphomas have a favorable prognosis; a high proportion of them have MALT characteristics.

Adult↗
PubMed1995

Intercellular adhesion molecule 1 (ICAM-1) and bcl-2 are differentially expressed in early evolving malignant melanoma.

The expression of intercellular adhesion molecule 1 (ICAM-1), a molecule pivotal in many inflammatory and immune paracrine interactions, has been highly correlated with malignant melanoma (MM) progression. Because numerous parallels exist between tissues of neural crest origin and the immune system in the regulation of postmitotic cell survival, ICAM-1 expression was studied in MM and compared with that of B-cell lymphoma/leukemia 2 protein (bcl-2 oncoprotein), an important regulator in prolonging lymphoid cell survival by blocking programmed cell death. Frozen sections from 33 cases were studied by immunoperoxidase techniques: 14 primary MM (five in situ), nine metastatic MM (one epidermotropic), four melanocytic nevi, and six normal skin controls. The percentages of the cells that stained and their intensities (0-4+) were graded. Both ICAM-1 (90%, 3-4+) and bcl-2 (95%, 2-4+) were strongly expressed in all nine metastases, including the epidermotropic disease extension. Bcl-2 strongly decorated the tumor cells in all 14 cases of primary MM (80%, 2-4+); in the five in situ MM, bcl-2 stained the atypical melanocytes at the dermal-epidermal junction (DEJ) and throughout the epidermis (75%, 1-2+). In contrast, ICAM-1 was negative in the in situ MM. ICAM-1 expression became strong (85%, 2-4+) in the dermal component of early invasive disease. Both ICAM-1 and bcl-2 were expressed in melanocytic nevi, decreasing in intensity deep within the dermis as the nevus cells senesced ("matured"). Only bcl-2 was expressed in the normal melanocytes of the six skin controls. These data show that bcl-2 is constitutively expressed in normal melanocytes and melanocytic nevi and persists in the transformed cells of early and late MM. ICAM-1 is expressed only after dermal involvement occurs, both in melanocytic nevi and in invasive MM; it persists in metastatic disease. The coexpression of bcl-2 and ICAM-1 demonstrates another similarity between the immune and neural crest systems, but it does not define or necessarily imply any functional interaction between the two proteins. The intercellular relationship of these two molecules, if any, remains to be investigated.

Apoptosis↗
PubMed1995

Tumor vascularity is not a prognostic factor for malignant melanoma of the skin.

Tumor vascularity has been proposed as a prognostic indicator for a number of solid tumors. Although a correlation between microvessel number and metastatic behavior has also been suggested for cutaneous melanoma, the small number of cases studied to date allows one to draw only preliminary conclusions. In this study, we have assessed tumor vascularity in cutaneous melanoma by comparing 60 cases of metastasizing and non-metastasizing tumors matched for tumor thickness, age, sex, and anatomic site. Ulex europaeus agglutinin I appeared to be the most suitable vascular marker for this study. Our results indicate that there was no statistically significant difference between the two groups with regard to tumor vascularity. Even after identifying 15 cases of thin ( < 1.0 mm thick) melanoma, there was no significant difference in the number of microvessels between metastasizing and non-metastasizing tumors. Comparison of patterns of vascular microarchitecture also failed to discriminate between the two groups. Thus, our results indicate that tumor vascularity may not be an independent prognostic factor for cutaneous melanoma.

Adolescent↗
PubMed1994

Subcutaneous, catheter-related inflammation in a rabbit model correlates with peripheral vein phlebitis in human volunteers.

In the development of a polyurethane vascular catheter with anti-infective properties, it became desirable to develop a measure of tissue inflammation. This was investigated in a rabbit model by implanting uncoated catheters and catheters coated with heparin (HEP), chlorhexidine (CH), or CH/HEP in the subcutaneous space with or without 10(4) Staphylococcus aureus. At intervals of 2, 4, and 7 days after implantation, animals were sacrificed; tissue blocks containing catheters were removed and preserved with formaldehyde; and sections were stained with hematoxylin and eosin. Using a histologic index, 240 sections (10 for each experimental condition) were evaluated by two investigators blinded to experimental conditions. Uncoated catheters or catheters coated with CH alone had a lower histologic index (less inflammation) than catheters coated with HEP alone or CH/HEP (P < .05). When catheters were inoculated with S. aureus, those coated with CH, with or without HEP, had a lower histologic index than uncoated catheters (P < .05). Next, 30 volunteers had a control catheter inserted in a vein in one forearm and a catheter coated with either CH alone or CH/HEP in a vein in the other forearm. After 96 h of observation there was a greater risk of phlebitis associated with CH/HEP catheters than control catheters (P < .05), and no difference in the risk of phlebitis between CH catheters and control catheters (P = 0.43). Thus, the amount of inflammation around the catheter in the subcutaneous space of rabbit correlated with the risk of peripheral vein phlebitis.

Adult↗
PubMed1994

Low-dose methotrexate treatment in elderly patients with bullous pemphigoid.

BACKGROUND: Various treatments have been used for elderly patients with bullous pemphigoid. The most common is moderate-dose to high-dose prednisone, either alone or in combination with other oral or topical agents. OBJECTIVE: The aim of this study was to evaluate the efficacy of low-dose methotrexate as a steroid-sparing agent in patients with bullous pemphigoid. METHODS. A retrospective chart review of 34 patients with bullous pemphigoid seen from 1989 through the first half of 1993 was conducted. The diagnosis of bullous pemphigoid was confirmed by direct or indirect immunofluorescence microscopy, or salt-split skin sections. Eight of 34 elderly (> 60 years old) patients with therapy-resistant bullous pemphigoid received low-dose weekly methotrexate (average, 5 to 10 mg) in combination with oral prednisone. RESULTS: Patients who received combination therapy required significantly lower (p < or = 0.02) doses of prednisone to control their disease at 1 month compared with baseline doses. CONCLUSION: In this elderly patient population the side effect profile of the methotrexate was acceptable and well tolerated. We therefore recommend methotrexate and low-dose corticosteroid as first-line combination therapy for selected elderly patients with bullous pemphigoid.

Administration, Oral↗
PubMed1994

Evaluation of immunoperoxidase techniques to detect Rickettsia rickettsii in fixed tissue sections.

Standard immunoperoxidase techniques were evaluated in the diagnosis of Rocky Mountain spotted fever (RMSF). Formalin-fixed, paraffin-embedded tissue was tested to detect Rickettsia rickettsii using the same antibody provided by the Centers for Disease Control and Prevention that is used for direct immunofluorescence (DIF). Tissues from 23 patients with suspected RMSF were divided: some were snap-frozen for DIF; the remainder were fixed in formalin, processed routinely, and embedded in paraffin for immunoperoxidase and hematoxylin and eosin staining. Ten patients were ultimately determined to have RMSF; in nine of these patients, both DIF and immunoperoxidase staining were positive for R rickettsii. There were no discrepancies, positive or negative, between the two methods. In the one case with a false-negative result by both methods, the patient had received antirickettsial antibiotics 72 hours before the biopsy was performed. These data demonstrate that the immunoperoxidase technique is effective in diagnosing RMSF and may be applied to cases retrospectively.

Adolescent↗
PubMed1994

Clinical application of polymerase chain reaction amplification to diagnosis of herpes virus infection.

Amplification of viral DNA offers a potentially sensitive and specific method for identifying herpes viruses in pathologic specimens. The purpose of this study is to assess the value of polymerase chain reaction amplification of DNA as a diagnostic test for herpes virus in pathologic specimens. The purpose of this study is to assess for herpes virus infections. We examined 79 paraffin-embedded tissue samples from 43 patients and 55 viral culture samples from 45 patients. Herpes virus DNA in the specimens was amplified by polymerase chain reaction. Using paraffin-embedded tissue on which a diagnosis of herpes virus was made by morphologic criteria, 11 of 19 patients had herpes virus DNA identified by PCR; herpes virus DNA was not identified in any of 35 negative control specimens. Herpes virus DNA was also identified by polymerase chain reaction in all of the positive herpes virus culture specimens. Of 29 culture negative specimens, herpes virus DNA was identified in six. We conclude that polymerase chain reaction is useful to establish or confirm the presence of a herpes virus infection in paraffin-embedded tissue samples and that it is more sensitive than viral culture.

DNA, Viral↗
PubMed1994

Epidermotropic metastatic malignant melanoma simulating melanoma in situ. A report of 10 examples from two patients.

Epidermotropic metastatic malignant melanoma (EMMM) is a well-recognized entity that can simulate primary malignant melanoma, and in the past reports of numerous (> or = 100) such lesions were misconstrued as multiple primary lesions. We present the cases of two patients who had not only numerous epidermotropic metastases that simulated primary melanomas but also 10 lesions that mimicked melanoma in situ. After removal of a primary malignant melanoma, the two patients developed 35 and 22 epidermotropic metastases over a 4-year period before dying with brain and pulmonary metastases, respectively. In these patients, 29 and 22 of the skin lesions were excised, respectively. All had epidermotropic metastases, of which seven and three showed pagetoid melanocytes in a pagetoid pattern exclusively within the epidermis and epithelial structures of adnexa, an "epidermal only" (in situ) pattern. Other lesions showed a continuum of dermal involvement, from the more conventional description of EMMM with the extent of dermal involvement > or = epidermal (n = 2) to epidermal involvement > dermal disease (n = 36). This histologic spectrum of dermal versus epidermal involvement in conjunction with the extremely small size (2.8 mm average histologic diameter), symmetry, large number, and time course of development argues strongly that these lesions represent metastases rather than multiple primary melanomas. The lesions illustrate the diagnostic dilemma posed by EMMM that simulates primary melanoma and further exhibits an "epidermal only" (melanoma in situ) pattern.

Adult↗
PubMed1994

Bacillary angiomatosis in an immunocompetent child: the first reported case.

Bacillary angiomatosis, an infectious process associated with Rochalima spp., was thought until recently to be restricted to HIV-infected or otherwise immunosuppressed patients. In 1993, bacillary angiomatosis was reported in several immunocompetent adults. An extensive literature review failed to find references to bacillary angiomatosis in immunocompetent children. We describe a 6-year-old female who presented with a single, rapidly growing, friable, erythematous papule on her neck. Histologic examination of a biopsy specimen confirmed the diagnosis of bacillary angiomatosis. The patient was otherwise healthy, and her physical examination was normal. Laboratory studies, including HIV serology, were normal. The patient was treated with six weeks of oral erythromycin without evidence of recurrence. We present and discuss the implications of the first case of bacillary angiomatosis in an immunocompetent child.

Angiomatosis, Bacillary↗