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165 result(s) for "Barrios, Patricia"
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Levamisole-Induced Vasculitis: A Characteristic Cutaneous Vasculitis Associated With Levamisole-Adulterated Cocaine
Levamisole-induced vasculitis is a characteristic cutaneous vasculitis syndrome associated with the use of levamisole-adulterated cocaine. Patients will typically present with a painful, purpuric rash in a retiform or stellate pattern with or without central necrosis involving the extremities, trunk, nasal tip, digits, cheeks, and/or ears. A history of cocaine abuse can be elicited. Histologic features include microvascular thrombi and/or leukocytoclastic vasculitis involving small vessels of the superficial and deep dermis. Epidermal involvement is variably seen. Laboratory findings include leukopenia, neutropenia (including agranulocytosis), elevated erythrocyte sedimentation rate, normal coagulation studies, and positive autoantibodies including perinuclear and cytoplasmic antineutrophil cytoplasmic antibodies, antinuclear antibody, and lupus anticoagulant. Differential diagnosis includes other microscopic vasculitides, and clinical and laboratory correlation with histologic findings is essential. Lesions typically resolve with the cessation of cocaine use. Because of the treatment implications and rising incidence of this entity, rapid and accurate diagnosis is essential.
Multifocal Retinocytoma Associated With Intronic Acceptor Splice Site Variants in the RB1 Gene
Retinocytomas are benign tumors that arise from mutations in the   gene. Previous research describes the appearance of retinocytomas as that of treated retinoblastoma (Rb) lesions, with characteristics such as chorioretinal atrophy, calcification, and a lack of necrosis or mitotic activity on histopathology. We present the unusual case of an asymptomatic seven-year-old girl with two independent translucent masses in the peripheral retina of the right eye (OD) and extensive intraretinal tumor and vitreous seeds. Initial fundus examination and B-scan ultrasonography documented the two lesions with extensive placoid intraretinal tumor, uncalcified vitreous seeds, and an area of large subhyaloid seed on the optic nerve (ON) head. Given the clinical appearance and elevated intraocular pressure (IOP), the eye was staged as Group E and enucleated. Histopathology performed on the enucleated specimen revealed pure retinocytoma with two predominant retinal tumors, extensive flat intraretinal tumor, large subhyaloid seeds over the inner limiting membrane of the ON and focally central retina and localized uncalcified vitreous seeds with no malignant Rb component. A next-generation sequencing (NGS) panel detected two intronic acceptor splice site variants in the gene. While the previous literature documents cases of retinocytoma with vitreous seeds, this is the first case to our knowledge of a sporadic multifocal retinocytoma with a large ON prelimiting membrane, subhyaloid seeds, and vitreous seeds associated with two intronic acceptor splice site variants in the gene and no other detectable mutations.
Inhibition of experimental corneal neovascularisation by bevacizumab (Avastin)
Aim: To evaluate the effect of topically administered bevacizumab (Avastin) on experimental corneal neovascularisation in rats. Methods: Silver nitrate sticks (75% silver nitrate, 25% potassium nitrate) were used to perform chemical cauterisation on the corneas of 16 eyes from 16 male Long Evans rats. For the following 7 days, the 10 eyes in the treatment group were instilled with bevacizumab 4 mg/ml drops twice daily, whereas the 6 eyes in the control group received placebo (normal saline drops twice daily). Digital photographs of the cornea were analysed to determine the area of cornea covered by neovascularisation as a percentage of the total corneal area. Results: In the bevacizumab-treated eyes, neovascularisation covered, on average, 38.2% (15.5%) (mean (SD)) of the corneal surface compared with 63.5% (5.0%) in the control group (p<0.02, Mann–Whitney U test). Conclusion: Topically administered bevacizumab (Avastin) at a concentration of 4 mg/ml limits corneal neovascularisation following chemical injury in the male Long Evans rat model.
Establishing the Clinical Utility of ctDNA Analysis for Diagnosis, Prognosis, and Treatment Monitoring of Retinoblastoma: The Aqueous Humor Liquid Biopsy
Because direct tumor biopsy is prohibited for retinoblastoma (RB), eye-specific molecular biomarkers are not used in clinical practice for RB. Recently, we demonstrated that the aqueous humor (AH) is a rich liquid biopsy source of cell-free tumor DNA. Herein, we detail clinically-relevant molecular biomarkers from the first year of prospective validation data. Seven eyes from 6 RB patients who had AH sampled at diagnosis and throughout therapy with ≥12 months of follow-up were included. Cell-free DNA (cfDNA) from each sample was isolated and sequenced to assess genome-wide somatic copy number alterations (SCNAs), followed by targeted resequencing for pathogenic variants using a RB1 and MYCN custom hybridization panel. Tumoral genomic information was detected in 100% of diagnostic AH samples. Of the seven diagnostic AH samples, 5/7 were positive for RB SCNAs. Mutational analysis identified RB1 variants in 5/7 AH samples, including the 2 samples in which no SCNAs were detected. Two eyes failed therapy and required enucleation; both had poor prognostic biomarkers (chromosome 6p gain or MYCN amplification) present in the AH at the time of diagnosis. In the context of previously established pre-analytical, analytical, and clinical validity, this provides evidence for larger, prospective studies to further establish the clinical utility of the AH liquid biopsy and its applications to precision oncology for RB.
Proceedings of the Consensus Meetings From the International Retinoblastoma Staging Working Group on the Pathology Guidelines for the Examination of Enucleated Eyes and Evaluation of Prognostic Risk Factors in Retinoblastoma
Retinoblastoma is the most common intraocular malignant childhood tumor in need of prospective clinical trials to address important unanswered questions about biology, treatment, and prognostic factors. Currently, there is controversy about the definitions for choroidal invasion and an inconsistency in the handling of eyes with retinoblastoma. The International Retinoblastoma Staging Working Group (IRSWG) composed of 58 participants from 24 countries on 4 continents had a series of Internet meetings to discuss the staging and tissue handling guidelines to reach consensus for adequate processing, establishing definitions of histopathologic risk factors, and reporting of enucleated eyes with retinoblastoma to serve as the basis for clinical trials and studies to validate the proposed criteria. The meetings were facilitated by the International Outreach Program of the St. Jude Children's Research Hospital through Cure4Kids. The retinoblastoma guidelines from the Children's Oncology Group, the French Society for Pediatric Cancers, the Association of Directors of Anatomic and Surgical Pathology, and some published data were the basis for this consensus document. Discussions of the feasibility, practicality, and efficacy of the guidelines and criteria resulted in this report. The consensus definitions reached included definition of massive choroidal invasion stated as a maximum diameter of invasive tumor focus of 3 mm or more that may reach the scleral tissue. Focal choroidal invasion is defined as a tumor focus of less than 3 mm and not reaching the sclera. Optic nerve invasion is classified as prelaminar, laminar, retrolaminar, or tumor at surgical margin, and the measurement of the depth of invasion should also be recorded. These guidelines also address handling of the enucleated eye with retinoblastoma in an efficient, practical, and feasible manner for a meaningful diagnosis. The consensus criteria reached by the IRSWG should be validated through prospective clinical trials and studies.
Eye cancer in a young male with a vaping history
We report a new observation of conjunctival intraepithelial neoplasia (CIN) in a young man following years of electronic cigarette use. A 22-year-old man with a 5-year electronic cigarette use (vaping) developed painless unilateral blurred vision in the right eye from mild superficial corneal opacification, unresponsive to topical antiviral therapy. Corneal scraping documented no infectious etiology. The abnormality persisted for 1 year and superficial keratectomy revealed high-grade CIN with enlarged pleomorphic and dyskeratotic cells. Interferon-alpha-2b was instituted. In this case, chronic exposure to electronic cigarette vapors (vaping) could have been associated with CIN in this young patient.
Tumorspheres but Not Adherent Cells Derived from Retinoblastoma Tumors Are of Malignant Origin
Verification that cell lines used for cancer research are derived from malignant cells in primary tumors is imperative to avoid invalidation of study results. Retinoblastoma is a childhood ocular tumor that develops from loss of functional retinoblastoma protein (pRb) as a result of genetic or epigenetic changes that affect both alleles of the RB1 gene. These patients contain unique identifiable genetic signatures specifically present in malignant cells. Primary cultures derived from retinoblastoma tumors can be established as non-adherent tumorspheres when grown in defined media or as attached monolayers when grown in serum-containing media. While the RB1 genotypes of tumorspheres match those of the primary tumor, adherent cultures have the germline RB1 genotype. Tumorspheres derived from pRb-negative tumors do not express pRb and express the neuroendocrine tumor markers synaptophysin and microtubule-associated protein 2 (MAP2). Adherent cells are synaptophysin-negative and express pRb, the epithelial cell marker cytokeratin that is expressed in the retinal pigmented epithelium and the vascular endothelial cell marker CD34. While tumorspheres are of malignant origin, our results cast doubt on the assumption that adherent tumor-derived cultures are always valid in vitro models of malignant cells and emphasize the need for validation of primary tumor cultures.
Expression of Angiogenic Factors in Invasive Retinoblastoma Tumors Is Associated With Increase in Tumor Cells Expressing Stem Cell Marker Sox2
Progression of retinoblastoma is associated with increased tumor angiogenesis. However, a clear relationship between the expression of angiogenic markers in specific regions of the tumor and tumor progression has not been established. This study investigates the association between angiogenic factors in retinoblastomas with choroidal and/or optic nerve invasion (high-risk/invasive retinoblastoma) and expression of Sox2, a stem cell marker. To investigate the association between the expression of angiogenic factors and markers of tumor invasiveness, such as the stem cell marker Sox2, in retinoblastoma tissues. Immunohistochemistry was used to evaluate coexpression of the angiogenic growth factors vascular endothelial growth factor A (VEGF-A), VEGF receptor 2 (VEGFR-2), and endoglin (CD105); markers of glial differentiation (vimentin and glial fibrillary acidic protein); and a neural stem cell marker (Sox2). Expression was assessed in nonneoplastic and neoplastic ocular tissues collected from enucleated eyes of patients with retinoblastoma. During qualitative data interpretation, evaluating pathologists were masked to patient grouping. Expression of VEGF-A and VEGFR-2 in noninvasive (non-high-risk feature) retinoblastoma tumors was lower than in the invasive, or high-risk feature tumors. Moreover, our data indicate that the tumor cells, and not the surrounding stroma, secrete VEGF-A and that angiogenesis is mostly localized to the iris. Finally, our data showed that the expression of the neural stem cell marker Sox2 is associated with eyes with increased VEGF-A expression and tumor invasiveness. Increased expression of angiogenic factors, with a concomitant increase in expression of the stem cell marker Sox2 observed in retinoblastoma tissues, may partially explain the aggressiveness of these tumors. The complex interaction of angiogenic and stem cell-related pathways in these tumors, especially in high-risk feature retinoblastoma, suggests that targeting tumor cells capable of secreting vasculogenic factors, as well as proangiogenic genes and signaling pathways, may be necessary for development of effective antimetastatic retinoblastoma drugs.
Locally Invasive Diffuse Iris Ring Melanoma Presenting as Unilateral Severe Glaucoma: Case Report and Review of Molecular Genetics
We report the clinical history and histopathological findings in a case of diffuse iris ring melanoma (DIM) and review the most recent literature and modern molecular genetics of this entity. An 85-year-old Hispanic man presented with severe unilateral glaucoma, managed at an outside institution for 2 years prior to presentation. Diffuse pigmentation was noted in the angle, on the intraocular lens implant, and in the vitreous without clear demonstration of a mass on ultrasound biomicroscopy. Workup for metastatic cutaneous melanoma was negative. Histopathological examination of the enucleated eye revealed a mixed cell type iris ring melanoma with diffuse intraocular involvement. Gene expression profiling (GEP) revealed a class 2 molecular signature indicating a very high risk for metastases. Unilateral glaucoma presenting with marked pigmentation in the anterior chamber angle should be managed as melanoma until proven otherwise. Iris ring melanomas are known to have an aggressive clinical course, and recent molecular analyses indicate that they are likely primarily GEP class 2 with a very poor prognosis, similar to the majority of ciliary body melanomas.