Helen Dimaras

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BACKGROUND Retinoblastoma is the childhood retinal cancer that defined tumour-suppressor genes. Previous work shows that mutation of both alleles of the RB1 retinoblastoma suppressor gene initiates disease. We aimed to characterise non-familial retinoblastoma tumours with no detectable RB1 mutations. METHODS Of 1068 unilateral non-familial retinoblastoma(More)
Retinoblastoma clinical observations revealed the role of tumor suppressor genes in human cancer, Knudson's 'two-hit' model of cancer induction. We now demonstrate that loss of both RB1 tumor suppressor gene alleles initiates quiescent RB1(-/-) retinomas with low level genomic instability and high expression of the senescence-associated proteins p16(INK4a)(More)
Retinoblastoma is a paediatric ocular tumour that continues to reveal much about the genetic basis of cancer development. Study of genomic aberrations in retinoblastoma tumours has exposed important mechanisms of cancer development and identified oncogenes and tumour suppressors that offer potential points of therapeutic intervention. The recent development(More)
PURPOSE Human retinoblastoma arises from an undefined developing retinal cell after inactivation of RB1. This is emulated in a murine retinoblastoma model by inactivation of pRB by retinal-specific expression of simian virus 40 large T-antigen (TAg-RB). Some mutational events after RB1 loss in humans are recapitulated at the expression level in TAg-RB,(More)
PURPOSE To evaluate knowledge of retinoblastoma inheritance among parents of children with familial retinoblastoma, and to compare this to timing of eye examination for at-risk children, disease severity at diagnosis, treatment burden, and outcome. METHODS A retrospective review of familial retinoblastoma cases that presented at Alexandria Main University(More)
Retinoblastoma is the prototypic genetic cancer. India carries the biggest burden of retinoblastoma globally, with an estimated 1500 new cases annually. Recent advances in retinoblastoma genetics are reviewed, focusing specifically on information with clinical significance to patients. The Indian literature on retinoblastoma clinical genetics is also(More)
BACKGROUND Strategic, interdisciplinary partnerships are essential to addressing the complex drivers of health inequities that result in survival disparities worldwide. Take for example the aggressive early childhood eye cancer retinoblastoma, where survival reaches 97 % in resource-rich countries, but is as low 30 % in some resource-limited nations, where(More)
PURPOSE Initial response of intraocular retinoblastoma to chemotherapy has encouraged primary chemotherapy instead of primary enucleation for eyes with clinical features suggesting high risk of extraocular extension or metastasis. Upfront enucleation of such high-risk eyes allows pathologic evaluation of extraocular extension, key to management with(More)
PURPOSE Hand-held spectral domain optical coherence tomography (HHSD OCT) has greatly expanded the imaging/diagnostic capacity for clinicians managing children with intraocular retinoblastoma. We present our early experience with HHSD OCT and conventional spectral domain OCT imaging in these patients. METHODS In this retrospective cross-sectional(More)
OBJECTIVE To review the effectiveness and toxicity of periocular topotecan hydrochloride in fibrin sealant (Tisseel) for the control of intraocular retinoblastoma. METHODS Retrospective medical record review of visually threatening or recurrent intraocular retinoblastoma treated with periocular topotecan. RESULTS Eight children (10 eyes) received 1 to 4(More)