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Dive into the research topics where Valerie A. White is active.

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Featured researches published by Valerie A. White.


Cancer | 1998

Correlation of cytogenetic abnormalities with the outcome of patients with uveal melanoma

Valerie A. White; Jeffrey D. Chambers; Paul Courtright; Wilma Y. Chang; Douglas E. Horsman

Cytogenetic investigations of choroid and ciliary body melanomas have revealed that the majority of cases are characterized by recurrent clonal abnormalities involving chromosomes 3, 6, and 8. The authors sought to determine whether these abnormalities were associated with outcome.


Ophthalmology | 2003

Optic nerve sheath meningiomas.

Peerooz Saeed; Jack Rootman; Robert A. Nugent; Valerie A. White; Ian R. Mackenzie; Leo Koornneef

PURPOSE To study the natural history and growth of optic nerve sheath meningiomas and evaluate their management outcome. DESIGN Clinicopathologic retrospective noncomparative case series. METHODS A retrospective study of 88 patients who were treated between 1976 and 1999 at the University of British Columbia and the University of Amsterdam. Clinical reports, imaging studies, and histopathologic findings were reviewed. RESULTS The mean age at onset of symptoms was 40.3 years, and most were seen in middle-aged females. Patients typically presented with visual loss, frequently associated with optic atrophy or papilledema and occasionally optociliary shunt vessels. On imaging, the optic nerve demonstrated segmental or diffuse thickening of the sheath or globular growth. Calcification was seen in 31% of cases and was associated with slower tumor growth. Tumors with posterior components in the orbit had more frequent intracranial involvement. Intracranial extension was more frequent and had a greater growth rate in younger patients. Irregular margins in the orbit implied local invasion. A presenting visual acuity better than 20/50 correlated with longer preservation of vision. Patients who underwent radiotherapy showed improvement in their visual acuity, and tumor growth was halted. Optic sheath decompression did not preserve vision. En bloc tumor excision was associated with no detectable recurrence in contrast to debulked tumors that recurred. CONCLUSIONS Meningiomas show characteristic indolent growth. Management therefore should be conservative in most cases. Radiotherapy is indicated in patients with progressive visual deterioration. Surgery, when indicated, should be an en bloc excision.


Ophthalmology | 1994

Idiopathic Sclerosing Inflammation of the Orbit: A Distinct Clinicopathologic Entity

Jack Rootman; Martin McCarthy; Valerie A. White; Gerald J. Harris; John S. Kennerdell

BACKGROUND Idiopathic sclerosing inflammation of the orbit is a poorly delineated, fibrosing, immune-mediated entity resulting in significant ocular disability. To characterize this process and propose more specific and effective therapy, clinical and pathologic findings in 16 cases are reviewed. METHODS The clinical records of 16 patients with biopsy-proven disease were retrospectively reviewed to determine demographic and clinical features, radiologic features, course, management, and outcome. These findings were correlated with pathologic features to describe this unique entity. Immunohistologic characteristics were compared with those of a clinically and histopathologically similar process, retroperitoneal fibrosis. RESULTS The study included 11 male and 5 female patients, ranging in age from 8 to 81 years. Disease onset was usually unilateral (14/16) and chronic (11/15), with two distinct anatomic presentations, lacrimal (11/16) and apical (3/16), characterized by infiltration (15/16), mass effect (12/16), and visual loss (3/16). The most common signs and symptoms were dull pain (13/16), proptosis (11/16), mild inflammation (11/16), restricted motility (9/16), swelling (9/16), and diplopia (8/16). Two features, a sparse, chronic inflammatory infiltrate, the immunopathologic characteristics of which suggested a cell-mediated process, and a desmoplastic stroma of early onset, dominated the pathologic picture. Treatment with corticosteroids (11/16), radiotherapy for steroid failures (8/11), and observation alone (3/16) was inadequate, resulting in blindness in 3/16 cases, restricted movement in 10/16, and complete resolution in only 2/16 patients. CONCLUSION Idiopathic sclerosing inflammation of the orbit is a unique clinicopathologic entity, similar to retroperitoneal fibrosis, that is characterized by primary, chronic, and immunologically mediated fibrosis, poor response to corticosteroid treatment or radiotherapy, and frequent visual disability. Early and aggressive immunosuppressive therapy is recommended.


International Journal of Cancer | 2004

Dissecting karyotypic patterns in malignant melanomas: Temporal clustering of losses and gains in melanoma karyotypic evolution.

Mattias Höglund; David Gisselsson; Gunnar B. Hansen; Valerie A. White; Torbjörn Säll; Felix Mitelman; Douglas E. Horsman

Malignant melanomas can be divided into two major subtypes, involving either the skin or eye melanomas. Both tumor forms exhibit highly complex karyotypes with nonrandom recurrent chromosomal imbalances. Loss of chromosome 3, the short arm of chromosome 1, and gain of 8q have been suggested to be associated with eye melanomas, whereas gain of 6p and loss of 6q have been more often seen in skin melanomas. Imbalances implicated in tumor progression include among others, −10 and +7. In spite of the abundance of cytogenetic information, with more than 300 published karyotypes, very little is known about the mode of karyotypic evolution or of the presence of possible cytogenetic pathways. In our investigation, we have used 362 melanoma karyotypes, including both the skin and eye subtypes, to identify the most frequently occurring imbalances. Tumor cases were then classified with respect to the presence or absence of these imbalances and statistically analyzed in order to assess the order of appearance of chromosomal imbalances, the presence of karyotypic pathways, as well as possible cytogenetic subtypes. We show that the melanomas develop through one mode of karyotypic evolution, common to both low and high complexity karyotypes, and we establish the temporal order by which the different imbalances occur. By applying several statistical methods, we show that at least two cytogenetic pathways of clonal evolution exist in malignant melanomas, one initiated with −3 and one with +6p, and that these pathways operate in both skin and eye melanomas.


Cancer | 1993

Cytogenetic analysis of uveal melanoma consistent occurrence of monosomy 3 and trisomy 8q

Douglas E. Horsman; Valerie A. White

Background. The genetic alterations associated with the pathogenesis of uveal melanoma have not been determined. To address this issue, the authors performed a prospective cytogenetic study of 35 uveal melanomas, including 23 primary untreated tumors and 12 tumors that were removed after local radiation therapy.


British Journal of Ophthalmology | 2006

Adult xanthogranulomatous disease of the orbit and ocular adnexa: new immunohistochemical findings and clinical review

J A Sivak‐Callcott; Jack Rootman; S L Rasmussen; R A Nugent; Valerie A. White; D Paridaens; Z Currie; G Rose; B Clark; A A McNab; F V Buffam; J M Neigel; M Kazim

Background/aims: Adult xanthogranulomatous disease involving the ocular tissues is rare and poorly understood. Adult onset xanthogranuloma (AOX), adult onset asthma and periocular xanthogranuloma (AAPOX), necrobiotic xanthogranuloma (NBX), and Erdheim-Chester disease (ECD) are the four syndromes within this disorder, which is diagnosed by characteristic histopathology. Experience with eight cases prompted a multi-institutional effort to study the histopathology, immunohistochemistry, clinical findings, and systemic associations in this disorder. Methods: 22 cases, including histopathological slides, were compiled. Published reports were identified by an English language Medline search (1966–2005) and review of reference citations. Each case in this series and the literature was classified as one of four syndromes and then analysed for age onset, sex, skin xanthoma, orbital location, immune dysfunction, internal organ and bone lesions, treatment, and outcome. The histopathology in each of these cases was reviewed by two pathologists. Immunhistochemical stains (CD3, CD4, CD8, L26) were performed in 14 cases where unstained slides were available. Results: 137 cases were compiled. There was no sex or age difference between syndromes. AOX, AAPOX, NBX affect the anterior orbit, ECD tends to be diffuse and intraconal. Skin lesions are found in all the syndromes. Immune dysfunction was noted in all cases of AAPOX and NBX; 11% of NBX and all ECD patients had internal organ disease. Treatment included surgery, corticosteroids, other chemotherapeutic agents, radiotherapy, and combinations of these. No AOX or AAPOX deaths occurred; 66% of ECD patients died. All 22 cases had xanthoma cells; most had Touton giant cells. Lymphocytes were present in all cases and occurred as aggregates (mostly in AAPOX) or diffuse populations mixed with fibroblasts (mostly in ECD). Immunohistochemistry revealed the majority of these to be CD8+. Necrosis was most marked in NBX. Conclusion: Adult xanthogranuloma of the orbit is rare, making prospective evaluation or meta-analysis impossible. The best treatment is unknown but seems to be with multiagent chemotherapy guided by histopathological, immunohistochemical, and systemic findings.


PLOS ONE | 2009

Retinal Pathology of Pediatric Cerebral Malaria in Malawi

Valerie A. White; Susan Lewallen; Nicholas A. V. Beare; Malcolm E. Molyneux; Terrie E. Taylor

Introduction The causes of coma and death in cerebral malaria remain unknown. Malarial retinopathy has been identified as an important clinical sign in the diagnosis and prognosis of cerebral malaria. As part of a larger autopsy study to determine causes of death in children with coma presenting to hospital in Blantyre, Malawi, who were fully evaluated clinically prior to death, we examined the histopathology of eyes of patients who died and underwent autopsy. Methodology/Principal Findings Children with coma were admitted to the pediatric research ward, classified according to clinical definitions as having cerebral malaria or another cause of coma, evaluated and treated. The eyes were examined by direct and indirect ophthalmoscopy. If a child died and permission was given, a standardized autopsy was carried out. The patient was then assigned an actual cause of death according to the autopsy findings. The eyes were examined pathologically for hemorrhages, cystoid macular edema, parasite sequestration and thrombi. They were stained immunohistochemically for fibrin and CD61 to identify the components of thrombi, β-amyloid precursor protein to detect axonal damage, for fibrinogen to identify vascular leakage and for glial fibrillary acidic protein to detect gliosis. Sixty-four eyes from 64 patients were examined: 35 with cerebral malaria and 29 with comas of other causes. Cerebral malaria was distinguished by sequestration of parasitized erythrocytes, the presence and severity of retinal hemorrhages, the presence of cystoid macular edema, the occurrence and number of fibrin-platelet thrombi, the presence and amount of axonal damage and vascular leakage. Conclusions/Significance We found significant differences in retinal histopathology between patients who died of cerebral malaria and those with other diagnoses. These histopathological findings offer insights into the etiology of malarial retinopathy and provide a pathological basis for recently described retinal capillary non-perfusion in children with malarial retinopathy. Because of the similarities between the retina and the brain it also suggests mechanisms that may contribute to coma and death in cerebral malaria.


Cancer Genetics and Cytogenetics | 1998

Acquired Homozygosity (Isodisomy) of Chromosome 3 in Uveal Melanoma

Valerie A. White; B.Kelly McNeil; Douglas E. Horsman

Cytogenetic investigation of uveal melanoma (UM) has revealed that monosomy 3 is the most frequent karyotypic abnormality, present in approximately 60% of cases. We investigated a cohort of 41 cases of UM, 19 of which retained two apparently normal copies of chromosome 3. Investigation of loss of heterozygosity (LOH) status was undertaken in an attempt to detect subcytogenetic loss of genetic material in those cases with two copies of chromosome 3. DNA from peripheral blood lymphocytes and fresh frozen or paraffin-embedded tumor tissue from 19 patients was amplified by the polymerase chain reaction for polymorphic loci on chromosome 3, including dinucleotide repeats, a tetranucleotide repeat, and polymorphic restriction enzyme sites. Three tumors showed LOH at multiple informative loci on both short and long arms of chromosome 3. Two additional tumors showed localized LOH on 3q, which corresponded to large deletions seen by cytogenetic analysis. The remaining 16 tumors showed retention of heterozygosity at all informative loci. This study did not detect the presence of cryptic deletions but revealed instead complete chromosomal homozygosity or functional monosomy, which probably occurred by loss and then duplication of the remaining chromosome 3. The demonstration of acquired isodisomy (functional monosomy) in a subset of UM increases the percentage of cases with monosomy 3 and provides further evidence for a central role of chromosome 3 loss in the molecular pathogenesis of uveal melanoma.


Archives of Ophthalmology | 2009

Epithelial lacrimal gland tumors: pathologic classification and current understanding.

Ezekiel Weis; Jack Rootman; Thomas J. Joly; Kenneth W. Berean; Hind Alkatan; Sylvia Pasternak; Giulio Bonavolontà; Diego Strianese; Peerooz Saeed; Kenneth A. Feldman; Sumalee Vangveeravong; Jocelyne S. Lapointe; Valerie A. White

OBJECTIVE To apply the updated epithelial salivary gland classification scheme to a large cohort of lacrimal gland tumors so as to provide an updated lacrimal gland tumor classification scheme. METHODS A retrospective multicenter cohort study of 118 cases of epithelial neoplasia was undertaken. Main outcome measures included pathologic analysis, subtyping, and survival. RESULTS Of 118 cases, 17 (14%) were reclassified using the proposed expanded classification scheme based on the current World Health Organization classification of salivary gland tumors. The most frequent neoplasms were pleomorphic adenoma and adenoid cystic carcinoma, of which we highlight more unusual histologic features. Three tumors were found to be unclassifiable with the updated scheme, with 2 having histologically malignant features. Deficiencies and variations in pathologic assessment were noted. Variation in the histologic findings of pleomorphic adenoma and assessment of the extent of invasion of carcinoma ex pleomorphic adenoma were highlighted. CONCLUSIONS The use of the more histologically diverse classification of salivary gland tumors can be successfully applied to the epithelial lacrimal gland neoplasms. This expanded classification system led to reclassifying 14% of cases. Currently, there are no consistent pathologic standards for processing and evaluating these lesions.


Ophthalmology | 1991

Relation between Optic Nerve Axon Number and Axon Diameter to Scleral Canal Area

Frederick S. Mikelberg; Haile M. Yidegiligne; Valerie A. White; Michael Schulzer

To determine whether there are more axons present in eyes with larger optic discs, the authors studied 16 eyes from 16 individuals whose eyes were donated for corneal transplantation. For each nerve, the axon count, axon diameter, and scleral canal area was measured. Total axon count decreased with age. Mean axon diameter increased with age. There was no statistically significant relation detected between axon count and scleral canal area. Multiple regression revealed that when corrected for the effect of age, eyes with smaller scleral canal areas had larger number of axons.

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Jack Rootman

University of British Columbia

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Peter J. Dolman

University of British Columbia

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Douglas E. Horsman

University of British Columbia

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Gerald J. Harris

Medical College of Wisconsin

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Manraj K.S. Heran

University of British Columbia

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Dinesh Selva

Royal Adelaide Hospital

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Bobby S. Korn

University of California

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