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1,133 result(s) for "Retinal Neoplasms - pathology"
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Conservative treatment of retinoblastoma: a prospective phase II randomized trial of neoadjuvant chemotherapy followed by local treatments and chemothermotherapy
Purpose Intraocular retinoblastoma treatments often combine chemotherapy and focal treatments. A first prospective protocol of conservative treatments in our institution showed the efficacy of the use of two courses of chemoreduction with etoposide and carboplatin, followed by chemothermotherapy using carboplatin as a single agent and diode laser. In order to decrease the possible long-term toxicity of chemotherapy due to etoposide, a randomized neoadjuvant phase II protocol was conducted using vincristine–carboplatin vs etoposide–carboplatin. Patients and methods The study was proposed when initial tumor characteristics did not allow front-line local treatments. Patients included in this phase II noncomparative randomized study of neoadjuvant chemotherapy received vincristin–carboplatin (new arm) vs etoposide–carboplatin (our reference arm). They were subsequently treated by local treatments and chemothermotherapy. Primary end point was the need for secondary enucleation or external beam radiotherapy (EBRT) not exceeding 40% at 2 years. Results A total of 65 eyes in 55 children were included in the study (May 2004 to August 2009). Of these, 32 eyes (27 children) were treated in the arm etoposide–carboplatin and 33 eyes (28 children) in the arm vincristin–carboplatin. At 2 years after treatment, 23/33 (69.7%) eyes were treated and salvaged without EBRT or enucleation in the arm vincristin–carboplatin and 26/32 (81.2%) in the arm etoposide–carboplatin. Conclusion Even if the two treatment arms could be considered as sufficiently active according to the study decision rules, neoadjuvant chemotherapy by two cycles of vincristine–carboplatin followed by chemothermotherapy appear to offer less optimal local control than the etoposide–carboplatin combination.
A high-risk retinoblastoma subtype with stemness features, dedifferentiated cone states and neuronal/ganglion cell gene expression
Retinoblastoma is the most frequent intraocular malignancy in children, originating from a maturing cone precursor in the developing retina. Little is known on the molecular basis underlying the biological and clinical behavior of this cancer. Here, using multi-omics data, we demonstrate the existence of two retinoblastoma subtypes. Subtype 1, of earlier onset, includes most of the heritable forms. It harbors few genetic alterations other than the initiating RB1 inactivation and corresponds to differentiated tumors expressing mature cone markers. By contrast, subtype 2 tumors harbor frequent recurrent genetic alterations including MYCN -amplification. They express markers of less differentiated cone together with neuronal/ganglion cell markers with marked inter- and intra-tumor heterogeneity. The cone dedifferentiation in subtype 2 is associated with stemness features including low immune and interferon response, E2F and MYC/MYCN activation and a higher propensity for metastasis. The recognition of these two subtypes, one maintaining a cone-differentiated state, and the other, more aggressive, associated with cone dedifferentiation and expression of neuronal markers, opens up important biological and clinical perspectives for retinoblastomas. Retinoblastoma is the most frequent intraocular paediatric malignancy whose molecular basis remains poorly understood. Here, the authors perform multi-omic analysis and identify two subtypes; one in a cone differentiated state and one more aggressive showing cone dedifferentiation and expressing neuronal markers.
Retinoblastoma
Retinoblastoma is an aggressive eye cancer of infancy and childhood. Survival and the chance of saving vision depend on severity of disease at presentation. Retinoblastoma was the first tumour to draw attention to the genetic aetiology of cancer. Despite good understanding of its aetiology, mortality from retinoblastoma is about 70% in countries of low and middle income, where most affected children live. Poor public and medical awareness, and an absence of rigorous clinical trials to assess innovative treatments impede progress. Worldwide, most of the estimated 9000 newly diagnosed patients every year will die. However, global digital communications present opportunities to optimise standards of care for children and families affected by this rare and often devastating cancer. Parents are now leading the effort for widespread awareness of the danger of leucocoria. Genome-level technologies could make genetic testing a reality for every family affected by retinoblastoma. Best-practice guidelines, online sharing of pathological images, point-of-care data entry, multidisciplinary research, and clinical trials can reduce mortality. Most importantly, active participation of survivors and families will ensure that the whole wellbeing of the child is prioritised in any treatment plan.
Developmental stage-specific proliferation and retinoblastoma genesis in RB-deficient human but not mouse cone precursors
Most retinoblastomas initiate in response to the inactivation of the RB1 gene and loss of functional RB protein. The tumors may form with few additional genomic changes and develop after a premalignant retinoma phase. Despite this seemingly straightforward etiology, mouse models have not recapitulated the genetic, cellular, and stage-specific features of human retinoblastoma genesis. For example, whereas human retinoblastomas appear to derive from cone photoreceptor precursors, current mouse models develop tumors that derive from other retinal cell types. To investigate the basis of the human cone-specific oncogenesis, we compared developmental stage-specific cone precursor responses to RB loss in human and murine retina cultures and in cone-specific Rb1-knockout mice. We report that RB-depleted maturing (ARR3⁺) but not immature (ARR3⁻) human cone precursors enter the cell cycle, proliferate, and form retinoblastoma-like lesions with Flexner–Wintersteiner rosettes, then form low or nonproliferative premalignant retinoma-like lesions with fleurettes and p16INK4A and p130 expression, and finally form highly proliferative retinoblastoma-like masses. In contrast, inmurine retina, only RB-depleted immature (Arr3⁻) cone precursors entered the cell cycle, and they failed to progress from S to M phase. Moreover, whereas intrinsically highly expressed MDM2 and MYCN contribute to RB-depleted maturing (ARR3⁺) human cone precursor proliferation, ectopic MDM2 and Mycn promoted only immature (Arr3⁻) murine cone precursor cell-cycle entry. These findings demonstrate that developmental stage-specific as well as species- and cell type-specific features sensitize to RB1 inactivation and reveal the human cone precursors’ capacity to model retinoblastoma initiation, proliferation, premalignant arrest, and tumor growth.
Evaluation of intravitreal topotecan dose levels, toxicity and efficacy for retinoblastoma vitreous seeds: a preclinical and clinical study
BackgroundCurrent melphalan-based intravitreal regimens for retinoblastoma (RB) vitreous seeds cause retinal toxicity. We assessed the efficacy and toxicity of topotecan monotherapy compared with melphalan in our rabbit model and patient cohort.MethodsRabbit experiments: empiric pharmacokinetics were determined following topotecan injection. For topotecan (15 μg or 30 µg), melphalan (12.5 µg) or saline, toxicity was evaluated by serial electroretinography (ERG) and histopathology, and efficacy against vitreous seed xenografts was measured by tumour cell reduction and apoptosis induction. Patients: retrospective cohort study of 235 patients receiving 990 intravitreal injections of topotecan or melphalan.ResultsIntravitreal topotecan 30 µg (equals 60 µg in humans) achieved the IC90 across the rabbit vitreous. Three weekly topotecan injections (either 15 µg or 30 µg) caused no retinal toxicity in rabbits, whereas melphalan 12.5 µg (equals 25 µg in humans) reduced ERG amplitudes 42%–79%. Intravitreal topotecan 15 µg was equally effective to melphalan to treat WERI-Rb1 cell xenografts in rabbits (96% reduction for topotecan vs saline (p=0.004), 88% reduction for melphalan vs saline (p=0.004), topotecan vs melphalan, p=0.15). In our clinical study, patients received 881 monotherapy injections (48 topotecan, 833 melphalan). Patients receiving 20 µg or 30 µg topotecan demonstrated no significant ERG reductions; melphalan caused ERG reductions of 7.6 μV for every injection of 25 µg (p=0.03) or 30 µg (p<0.001). Most patients treated with intravitreal topotecan also received intravitreal melphalan at some point during their treatment course. Among those eyes treated exclusively with topotecan monotherapy, all eyes were salvaged.ConclusionsTaken together, these experiments suggest that intravitreal topotecan monotherapy for the treatment of RB vitreous seeds is non-toxic and effective.
Diffuse infiltrating retinoblastoma: a multicentre, international, data-sharing study
BackgroundTo determine the unique clinical characteristics and treatment outcomes of diffuse infiltrating retinoblastoma (DIR).MethodsThis international, multicentre, registry-based retrospective case series analysed pooled data from January 2001 to December 2013, including 132 eyes from 132 patients with DIR.ResultsAmong 2854 eyes with retinoblastoma, 132 (4.6%; 95% CI, 3.9 to 5.5) had DIR. The median age at diagnosis for DIR patients was 24 months (IQR, 15–33), with no bilateral cases of DIR. The American Joint Committee on Cancer staging showed 4.5% cT2 and 95.5% cT3 categories, with no cT1 or cT4 cases. Clinical features associated with DIR included secondary glaucoma (67%), retinal detachment (38%), diffuse vitreous seeds (37%), anterior segment involvement (24%), vitreous haemorrhage (50%) and hyphema (6%). Primary enucleation was the predominant treatment (81%), while 19% initially received systemic chemotherapy, with 6% requiring subsequent enucleation. The 5-year Kaplan-Meier survival rate for cT3 DIR was 82% (95% CI, 78 to 86), significantly lower than the 94% (95% CI, 93 to 95) for cT3 non-DIR cases (p<0.001). Cox proportional hazards regression returned a higher risk of metastatic death for DIR cT3 compared with non-DIR cT3 (HR, 3.3; 95% CI, 1.8 to 5.9; p<0.001). High-risk pathological features were more frequent in DIR (41% vs 28%, p=0.004). There was no association between DIR and local treatment failure.ConclusionsApproximately 1 in 20 patients with retinoblastoma had DIR, which often presented with glaucoma, anterior segment involvement or intraocular bleeding. DIR was more lethal than non-DIR cT3, with enucleation revealing high-risk pathology.
Exploring metabolic biomarkers in primary and chemoreduced retinoblastoma with patient outcome
AimsThe goal of this study is to identify the pathological findings and expression of metabolic markers (GLUT-1, PDK-1 and PGC1α) in the tumour microenvironment of both primary and chemoreduced retinoblastoma (Rb) and to correlate with clinicopathological parameters and patient outcome.Methods81 prospective cases were included, in which 53 cases underwent primary enucleation and 28 cases received chemotherapy before enucleation. Immunohistochemistry, qRT-PCR and western blotting were performed to evaluate the expression pattern of metabolic markers in primary and chemoreduced Rb.ResultsTumour microenvironment and histopathological findings were different for both primary and chemoreduced Rb. Increased immunohistochemical expression of GLUT-1, PDK-1 and PGC1α was found in primary Rb as compared with chemoreduced Rb. mRNA expression was also found to be upregulated in primary Rb compared with chemoreduced. On univariate analysis, the presence of more than one histopathological high-risk factor (HRFs>1) and PDK-1 immunoexpression was statistically significant with overall survival. On prognostication in primary and chemoreduced cases with hypoxia, we found increased HR in cases with retrolaminar ON invasion, presence of more than one HRF, and presence of PDK-1 and PGC-1α immunoexpression.ConclusionsThis is the first of its kind study predicting a relevant role of the metabolic markers in primary and chemoreduced Rb with prognostic significance. Differential expression of these markers in both groups of Rb is a novel finding and might be an interesting and beneficial target for the management of Rb patients.
Correlating somatic copy number alteration in aqueous humour cfDNA with chemotherapy history, eye salvage and pathological features in retinoblastoma
BackgroundThis study determined to probe the potential association between somatic copy number alteration (SCNA) in retinoblastoma (RB) aqueous humour (AH) and pathological high-risk factors, clinical features and previous chemotherapy history.MethodsSingle-centre retrospective cohort study from including 58 AH samples collected from 58 patients diagnosed. Among them, 41 samples were collected after enucleation and 17 samples were collected before intravitreal chemotherapy. SCNAs were accessed by conducting shallow whole-genome sequencing in cell-free (cf) DNA of AH. HRs and ORs were applied to measure risk factors.ResultsCanonical RB SCNAs including 1q gain (87%), 2p gain (50%), 6p gain (76%), 16q loss (69%) were frequently detected. Non-classical RB SCNAs in AH including 17q gain (53%), 19q loss (43%), 7q gain (35%) were also commonly observed. 19q loss was significantly more common in patients with cT3c or worse stage than others (p=0.034). 2p gain(p=0.001) and 7q gain(p=0.001) were both more common in patients with primary enucleation than those with previous chemotherapy. Interestingly, both 2p gain (HR=1.933, p=0.027) and 7q gain (HR=2.394, p=0.005) might predict enucleation. Correlation analysis with pathological features among enucleated eyes showed that 19q loss can predict a higher risk for both massive choroid invasion (OR=4.909, p=0.038) and postlaminar optic nerve invasion (OR=4.250, p=0.043).DiscussionSequencing of AH cfDNA in RB can provide sufficient in vivo information. 19q loss was a potential signature of advanced cases clinically and pathologically.Repeated sampling from eyes receiving sequential chemotherapy should be conducted to evaluate fluctuation of SCNA in future study.
Aurora borealis and string of pearls in vitreoretinal lymphoma: patterns of vitreous haze
AimsPeculiar retinal signs of vitreoretinal lymphoma (VRL) have been identified. However, limited information on the vitreous features of VRL is available. This study aims to characterise the vitreous involvement in VRL with the help of multimodal imaging.MethodsIn this retrospective, observational study, we reviewed charts and imaging of all patients with biopsy-proven VRL seen from January 2016 to April 2018 at a single referral centre. These included ultrawide-field imaging, ophthalmic ultrasonography and slit-lamp photography. The main outcome measures were patterns of vitreous haze of VRL, as observed by combining clinical and multimodal imaging information.ResultsTwenty-six eyes of 13 patients were included. At presentation, vitreous haze was present in 24 eyes (92%) and was the only sign of VRL in 4 eyes (15%). Three patterns of vitreous haze were identified in VRL. An aurora borealis pattern was present in 12 eyes and showed linear opacities with a myriad of cells aligned along the vitreous fibrils. A string of pearls pattern was present in two eyes at baseline and developed in other four eyes after vitrectomy, showing fine fibrils connecting bunches of inflammatory material. A non-specific pattern was observed in 10 eyes. Ophthalmic ultrasound showed corpuscular material correlating with the grading of vitreous haze.ConclusionVRL shows different patterns of vitreous haze. Multimodal imaging, including ultrawide-field imaging and slit-lamp photography, helps in recognising these patterns, raising suspicion for VRL.
An immature, dedifferentiated, and lineage-deconstrained cone precursor origin of N-Myc–initiated retinoblastoma
Most retinoblastomas develop from maturing cone precursors in response to biallelic RB1 loss and are dependent on cone maturation-related signaling. Additionally, ∼2% lack RB1 mutations but have MYCN amplification (MYCNA ), N-Myc protein overexpression, and more rapid and invasive growth, yet the MYCNA retinoblastoma cell of origin and basis for its responses to deregulated N-Myc are unknown. Here, using explanted cultured retinae, we show that ectopic N-Myc induces cell cycle entry in cells expressing markers of several retinal types yet induces continuous proliferation and tumorigenesis only in cone precursors. Unlike the response to RB1 loss, both immature cone arrestin-negative (ARR3⁻) and maturing ARR3⁺ cone precursors proliferate, and maturing cone precursors rapidly dedifferentiate, losing ARR3 as well as L/M-opsin expression. N-Myc–overexpressing retinal cells also lose cell lineage constraints, occasionally coexpressing the cone-specific RXRγ with the rod-specific NRL or amacrine-specific AP2α and widely coexpressing RXRγ with the progenitor and Müller cell–specific SOX9 and retinal ganglion cell-specific BRN3 and GAP43. Mechanistically, N-Myc induced Cyclin D2 and CDK4 overexpression, pRB phosphorylation, and SOX9-dependent proliferation without a retinoma-like stage that characterizes pRB-deficient retinoblastoma, despite continuous p16INK4A expression. Orthotopic xenografts of N-Myc–overexpressing retinal cells formed tumors with retinal cell marker expression similar to those in MYCN-transduced retinae and MYCNA retinoblastomas in patients. These findings demonstrate the MYCNA retinoblastoma origin from immature and lineage-deconstrained cone precursors, reveal their opportunistic use of an undifferentiated retinal progenitor cell feature, and illustrate that different cancer-initiating mutations cooperate with distinct developmental stage–specific cell signaling circuitries to drive retinoblastoma tumorigenesis.