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Featured researches published by M. Andrew Parsons.


Genes, Chromosomes and Cancer | 1997

Abnormalities of chromosomes 3 and 8 in posterior uveal melanoma correlate with prognosis

Karen Sisley; Ian G. Rennie; M. Andrew Parsons; Rhona Jacques; David W. Hammond; Sharon M. Bell; Am Potter; Robert C. Rees

Posterior uveal melanomas have nonrandom alterations affecting chromosomes 3, 6, and 8. Loss of chromosome 3 in uveal melanoma has been shown to act as a predictor of disease‐free and overall survival. To confirm the significance of chromosome 3 loss and to extend the observations to include those of the associated alterations of chromosome 8, we have conducted a cytogenetic analysis on a series of 42 tumours from patients with primary uveal melanoma who were followed up for a median of 31 months (range = 8‐96 months). Abnormalities of chromosomes 3 and 8 were the commonest changes and were confirmed in 10 tumours using flourescence in situ hybridization. Monosomy of chromosome 3 was found in 21 (50%) of the tumours, and 23 (54%) tumours had additional copies of 8q. Alterations of chromosomes 3 and 8 were found occurring together in 19 (45%) of the tumours and were significantly associated with a ciliary body component (P < 0.0001). Prognostic indicators and changes of chromosomes 3 and 8 were analysed for correlation with patient survival. Of the chosen parameters, only ciliary body involvement (P = 0.003), monosomy of chromosome 3 (P = 0.0007), and additional copies of 8q (P = 0.003) correlated with reducted survival. Evaluation of the dosage effect of additional copies of chromosome arm 8q showed a significant association with reduced survival (P = 0.0001), which was also predictive of a decreased disease‐free interval (P = 0.01). Thus, the cytogenetic analysis of uveal melanoma may provide a valuable predictor of prognosis. Genes Chromosom. Cancer 19:22–28, 1997.


British Journal of Ophthalmology | 2001

Prediction of prognosis in patients with uveal melanoma using fluorescence in situ hybridisation

Kirtikbhai A Patel; Noel D Edmondson; Fleur Talbot; M. Andrew Parsons; I G Rennie; Karen Sisley

BACKGROUND/AIMS Uveal melanoma is the commonest malignancy of the eye, with a high proportion of patients dying of metastatic disease. Tumours showing a loss of chromosome 3 and gains of chromosome 8 are associated with a worse prognosis. The efficiency of fluorescence in situ hybridisation (FISH) in determining copy numbers of these chromosomes was assessed in individual tumours and related to patient survival. METHODS 33 fresh frozen samples were analysed with centromeric probes for chromosomes 3 and 8. Patient outcomes were divided into two groups: (1) absence of genetic abnormalities (no genetic imbalance) and (2) presence of genetic abnormalities (genetic imbalance). The log rank test was used to compare survival, which was represented by Kaplan-Meier survival curves. RESULTS Of the 33 tumours analysed, 16 showed evidence of genetic imbalances. Of these 16 tumours, 14 patients had died by the end of the study, with 10 having died of liver metastases. Of the tumours without evidence of genetic imbalances, five patients had died by the end of the study, although none had died as a result of either liver metastases or from the primary uveal melanoma. The difference in survival between the two groups was highly significant (p<0.0001). CONCLUSION The authors have shown that FISH analysis for chromosome 3 and 8 is a reliable and efficient technique in the analysis of fresh frozen tumour specimens and is valuable in the prediction of prognosis in individuals with uveal melanomas.


American Journal of Forensic Medicine and Pathology | 2007

Guidelines for Postmortem Protocol for Ocular Investigation of Sudden Unexplained Infant Death and Suspected Physical Child Abuse

M. G. F. Gilliland; Alex V. Levin; Robert W. Enzenauer; Charles Smith; M. Andrew Parsons; Lucy B. Rorke-Adams; James R. Lauridson; Linda M. Christmann; Marcellina Mian; Jeffrey M. Jentzen; Kenneth B. Simons; Yair Morad; Randell Alexander; Carole Jenny; Tamara Wygnanski-Jaffe

Postmortem examination is a cornerstone in identifying the cause of unexplained sudden death in children. Even in cases of suspected or known abuse, an autopsy may help characterize the nature of the abuse, which is particularly important in the forensic autopsy of children in the first 3 to 4 years of life when inflicted neurotrauma is most common. Forensic examinations are vital in cases that might otherwise be diagnosed as sudden infant death syndrome. The ocular autopsy in particular may demonstrate findings that were not appreciated on antemortem clinical examination. This protocol for postmortem examination of the eyes and orbits was developed to promote more consistent documentation of findings, improved clinical and forensic decision making, and more replicable and coherent research outcomes.


Graefes Archive for Clinical and Experimental Ophthalmology | 1992

C-myc oncogene expression in ocular melanomas

Janice A. Royds; R. Michael Sharrard; M. Andrew Parsons; John Lawry; Robert C. Rees; David W. Cottam; Bart Wagner; Ian G. Rennie

We have investigated the expression of c-myc in 24 ocular melanomas by immunohistochemistry, using two monoclonal antibodies raised against a midsequence portion of the c-myc product (6E10) and against the C-terminus (9E10). The results were compared with other putative prognostic factors, including tumour size, cell type, proliferation index (determined by flow cytometry), and ploidy, as well as immunohistochemical staining for HMB-45 and S-100 antigens. Staining, often focal, for c-myc was found in both the nucleus and the cytoplasm of a proportion of the cells in most tumours studied. Total cell staining for myc protein correlated with proliferative index in diploid tumours; seven out of nine aneuploid and mixed aneuploid/diploid cells showed strong staining in at least one cellular compartment. A positive correlation with myc expression was also found for HMB-45 staining, but not for cell type or staining for S-100. The results support the hypothesis that myc protein is involved in cellular proliferation in uveal melanomas and indicate that immunohistochemistry for myc antigen may be a useful prognostic marker in these tumours.


Cancer Genetics and Cytogenetics | 1998

Cytogenetics of Iris Melanomas: Disparity with Other Uveal Tract Melanomas

Karen Sisley; Christopher Brand; M. Andrew Parsons; Edna Maltby; Robert C. Rees; Ian G. Rennie

The chromosomal alterations of iris melanomas are poorly characterized, only one report has been detailed. Cytogenetic analysis was performed on the tumors and heparinized blood samples of three patients with iris melanomas; in one case a primary tumor and its related seedling were examined. On analysis of lymphocytes, two of the patients were found to experience a low level fragility of chromosome 9, in the region of a cutaneous melanoma susceptibility gene. All iris melanoma lesions were karyotyped. Clonal abnormalities of chromosomes 3, 5, 6, 7, 8, 9, 12, 15, 17, 18, 19, and Y were found, and in one case a large number of marker chromosomes were observed. No specific chromosomal change was common to the iris melanomas, but two cases had different abnormalities of chromosomes 5 and 18. Variations between the primary tumor and its related seedling were the acquisition of an additional chromosome 15, and a polyploid form of the cell line in the seedling. This study suggests that the most common chromosomal changes of posterior uveal melanomas are less frequent in iris melanomas. Iris melanomas also appear to experience relatively high levels of chromosomal alterations, including the formation of marker chromosomes, which is perhaps reminiscent of cutaneous melanoma.


Ophthalmology | 2003

Foreign body episcleral granulomas complicating intravitreal silicone oil tamponade: A clinicopathological study

Sathish Srinivasan; Arvind K. Singh; Shrivatsa P Desai; John F. Talbot; M. Andrew Parsons

PURPOSE To report two patients with lipid granulomas of the episclera complicating vitrectomy and silicone oil tamponade. DESIGN Two observational case reports. INTERVENTION Patient 1, a 41-year-old woman, underwent vitrectomy with silicone oil tamponade for proliferative diabetic retinopathy. Four weeks later, she sought treatment for inflamed episcleral nodules adjacent to one of the sclerostomy sites. The oil was removed and the episcleral nodules were excised. Patient 2, a 33-year-old man, underwent vitrectomy and silicone oil tamponade for tractional retinal detachment. He experienced a painful blind eye with episcleral nodule that required enucleation. MAIN OUTCOME MEASURES On histopathological analysis, both specimens demonstrated episcleral granulomas caused by silicone oil. CONCLUSIONS Episcleral nodules adjacent to vitrectomy entry sites with silicone oil tamponade may represent lipid granulomas, probably caused by silicone oil leakage from scleral entry ports.


Archive | 2006

A Histopathologist’s Guide to Ocular Pathology

M. Andrew Parsons

Ophthalmic pathology at autopsy can seem a daunting business to the uninitiated. However, it has much to offer scientifically and diagnostically once the initial fears are overcome. The procedures are no more difficult — once learned — than those in many other branches of pathology. As ever, the “secret” is in good preparation and thoughtful and careful execution of all of the technical procedures. Therefore I encourage you to consider working in this extremely interesting area of pathology.


Genes, Chromosomes and Cancer | 1992

Non-random abnormalities of chromosomes 3, 6, and 8 associated with posterior uveal melanoma

Karen Sisley; David W. Cottam; Ian G. Rennie; M. Andrew Parsons; Am Potter; C. W. Potter; Robert C. Rees


Cancer Research | 2001

p53 and p21waf-1 Expression Correlates with Apoptosis or Cell Survival in Poorly Differentiated, but not Well-Differentiated, Retinoblastomas

Ayesha Divan; John Lawry; Ian R. Dunsmore; M. Andrew Parsons; Janice A. Royds


Investigative Ophthalmology & Visual Science | 2002

An In Vitro Assay to Assess Uveal Melanoma Invasion across Endothelial and Basement Membrane Barriers

Julia K. L. Woodward; Carmel E Nichols; I G Rennie; M. Andrew Parsons; Anna K. Murray; Karen Sisley

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Karen Sisley

University of Sheffield

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I G Rennie

Royal Hallamshire Hospital

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Robert C. Rees

Nottingham Trent University

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Am Potter

University of Sheffield

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John Lawry

University of Sheffield

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