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Background: Retinoblastoma (RB) is a malignant, childhood tumour of the developing retina that occurs with an estimated frequency of 1 in 20 000. Identification of oncogenic mutations in the RB1 gene aids in the clinical management of families with a heritable predisposition to RB. Here we present the spectrum of genetic and epigenetic changes identified in 194 tumours and 209 blood samples, from 403 unrelated RB patients., Methods: Mutation screening was carried out across all 27 RB1 exons and their associated splice sites. Small coding sequence changes were detected using fluorescent conformation analysis followed by sequencing. Large exonic deletions were detected by quantitative fluorescent PCR. Methylation specific PCR of the RB1 promoter was performed to detect epigenetic alterations. Polymorphism analysis was used to determine loss of heterozygosity in tumour samples., Results: 95% of the expected mutations were identified in the tumour samples, with 16 samples exhibiting only one mutation, while two samples had no detectable RB1 mutation. 96% of bilateral/familial RB blood samples and 9.5% of unilateral sporadic blood samples, yielded mutations. 111 were novel mutations., Conclusions: The full range of screening techniques is required to achieve a high screening sensitivity in RB patients.

Background/aims: To determine the frequency and cause of visual loss following intra-arterial melphalan (IAM) in patients with retinoblastoma with age appropriate vision., Methods: Assessment of patients with refractory retinoblastoma that had undergone systemic chemotherapy, with or without local treatment, and were subsequently treated with IAM. Eyes of patients with a healthy foveola were assessed. The main outcome measures included visual, macular (including Pattern Visual Evoked Potentials and Fundus Fluorescein Angiography) and retinal functions (Electroretinograms)., Results: Five of twelve eyes (42%) demonstrated severe visual loss following IAM at last follow-up (median 21 months). This was due to either retinal detachment (1 eye, 20%) or choroidal ischaemia involving the foveola (4 eyes, 80%). All 3 eyes that had technical difficulties or vasospasm during catheterisation suffered visual loss. 8 out of 10 eyes that had a non-age adjusted dose of melphalan suffered visual loss. Electroretinograms post-IAM deteriorated in 4 of 8 eyes (50%) and Pattern Visual Evoked Potentials deteriorated in 3 (37%), though only one of these 3 showed concomitant visual acuity loss., Conclusions: Structural and vascular damage to the foveola limited visual acuity. Complications associated with catheterisation and high doses of melphalan may be contributory factors to visual morbidity. Although visual loss is described, no patient developed metastases and most retained good vision.

Background: Retinoblastoma is an eye tumour of childhood that occurs in heritable and non-heritable forms. In the heritable form, there is a predisposition to the development of non-ocular subsequent primary tumours (SPTs)., Methods: This study included 1927 retinoblastoma patients diagnosed in Britain from 1951 to 2004. Ascertainment was through the (UK) National Registry of Childhood Tumours; cases were followed-up for the occurrence of SPTs. Standardised incidence ratios (SIRs) were calculated., Results: We identified 169 SPTs in 152 patients. The SIR analysis included 145 SPTs with cancer registrations from the years 1971 to 2009. These tumours occurred in 132 patients: 112 of the 781 heritable and 20 of the 1075 (presumed) non-heritable cases under surveillance at the start of this period developed at least one registered SPT. The SIRs for all tumours combined were 13.7 (95% confidence interval 11.3-16.5) in heritable cases and 1.5 (0.9-2.3) in non-heritable cases. The main types of SPT in the heritable cases were leiomyosarcoma, (31 cases; SIR 1018.7 (692.2-1446.0)), osteosarcoma (26 cases; SIR 444.6 (290.4-651.4)), and skin melanoma (12 cases; SIR 18.6 (9.6-32.4))., Conclusion: The risk of SPTs in heritable retinoblastoma is extremely high. This has important implications for the clinical follow-up and counselling of survivors and their families.

Heritable retinoblastoma is associated with a germline mutation in the tumour suppressor gene RBI. The Rb protein (pRb) arises from the RB1 gene, which was the first demonstrated cancer susceptibility gene in humans. Second primary malignancies are recognised complications of retinoblastoma. Furthermore, pRb is implicated in valve remodelling in calcific aortic valve disease. We report a family with hereditary retinoblastoma and associated secondary primary malignancies. There are two interesting aspects to this family. The first is the concept of 'cancer susceptibility genes'; the RBI gene being the first reported in humans. A further feature of note is that two family members also have bicuspid aortic valves. We discuss a potential association between the gene defect responsible for retinoblastoma (with its associated propensity for further malignancies) and accelerated deterioration of the bicuspid aortic valve in the proband carrying this gene defect.

Purpose: To report the efficacy of super-selective intra-ophthalmic artery melphalan (IAM) for the treatment of refractory retinoblastoma and any associated complications of this treatment., Design: A prospective case series., Participants: Eyes with retinoblastoma that had been treated with systemic chemotherapy or local therapy and had a relapse of their condition., Methods: All patients receiving IAM between May 2009 and September 2010 were included in the study. Intra-ophthalmic artery melphalan was offered to patients who had failed to respond adequately to systemic chemotherapy and local treatment where appropriate or because of a new recurrence of retinoblastoma that could not be treated with local therapies. None of the patients were excluded because of central nervous system abnormalities. Patients received 2 treatments of IAM given 4 weeks apart. All patients received an orthoptic assessment 3 weeks after each treatment and an examination under anesthesia (EUA). A third treatment was given if an unsatisfactory response was observed on EUA after 2 treatments., Main Outcome Measures: The response of the retinoblastoma tumor(s) and any associated local side effects from the treatment., Results: A total of 15 eyes in 14 patients were treated with IAM during the study period. The mean age at the time of IAM was 31.5 months (median 17.3, range 11.2-150.7 months), and the mean follow-up was 8.7 months (3-16.3 months). Tumor control was achieved in 12 eyes (80%), and 12 eyes (80%) had local side effects that included third cranial nerve palsy in 6 (40%), orbital edema in 3 (20%), permanent retinal detachment in 1 (7%), and vitreous hemorrhage in 4 (27%). Seven eyes (47%) developed significant retinal pigment epithelium changes., Conclusions: Intra-ophthalmic artery melphalan is an effective treatment for retinoblastoma, achieving a high level of remission in refractory tumors. It can be associated with significant local side effects that can result in loss of vision and possible amblyogenesis. Clinicians and parents need to consider the benefits and potential local side effects before embarking on treatment., (Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Background: Retinoblastoma occurs in both a heritable and a non-heritable form. In the heritable form, there is a predisposition to the development of non-ocular tumours., Objectives: To identify the types of non-ocular tumour occurring in retinoblastoma survivors and to produce estimates of risk for these tumours., Methods: We carried out a cohort study that included 1927 cases of retinoblastoma diagnosed in Great Britain between 1951 and 2004. Cases were ascertained through the National Registry of Childhood Tumours and followed up for the occurrence of non-ocular tumours using the routine notification system based on the National Health Service Central Registers in Britain., Results: Of the 1927 cases, 809 were known to have the heritable form of the disease and 1118 assumed to have the non-heritable form. 102 of the heritable and 13 of those classified as non-heritable developed a non-ocular tumour. The cumulative risk of developing such a tumour 50 years after retinoblastoma diagnosis was 48.3% (95% confidence interval: 38.1 to 59.7%) in the heritable and 4.9% (1.9 to 12.4%) in the non-heritable cases. The main categories of non-ocular tumours observed in the heritable cases were soft-tissue sarcomas (36 of which 21 were leiomyosarcoma), osteosarcoma (32), carcinoma (13), brain and central nervous system tumours (10), melanoma (9), leukaemia (4) and others (4). There were a total of 108 non-ocular tumours in 102 cases., Conclusions: There is a high risk of non-ocular tumours occurring in survivors of heritable retinoblastoma. These results have important implications for the clinical follow-up and counselling of survivors.

Background: Radiation is implicated in the induction of second malignancies in children with bilateral retinoblastoma. There is a need to determine whether this risk can be justified by good visual outcome when external beam radiotherapy (EBRT) is used as a salvage treatment., Aim: To study the effectiveness of EBRT as a salvage treatment after failed primary chemotherapy and focal treatment in bilateral retinoblastoma., Methods: This is a retrospective observational case series. The outcome measures after EBRT are: rate of eye preservation, rate of tumour control, visual potential, visual acuity and radiation-induced side-effects., Results: Thirty-six eyes (22 patients) were included. The median follow-up after EBRT was 40 months (19-165 months). Thirty-two eyes received lens-sparing radiotherapy, and four received whole-eye radiation. The rate of eye preservation was 83.3% (30/36 eyes). Twenty-four eyes (66.7%) were controlled by EBRT and required no further treatment. Of the 30 preserved eyes, 20 eyes (66.7%) had extramacular tumours without retinal detachment and therefore potential for central vision. The final visual acuity was recorded for 19 eyes. Ten eyes (52.6%) read 6/9-6/5, three eyes (15.8%) read 6/18-6/36, and six eyes (31.6%) read 6/60 or worse. Significant radiation- induced side effects were limited to cataracts and dry eyes with whole-eye radiation. There were no second cancers or deaths., Conclusion: Salvage EBRT is highly effective in preserving eyes with useful vision in bilateral retinoblastoma after failed chemotherapy and focal treatments. These results will help the parents and ophthalmologists of such patients to reach an informed decision when weighing up the benefits of EBRT against its potential oncogenic effect.

Aim: This paper describes the treatment and survival of 1576 children with retinoblastoma in Great Britain diagnosed 1963-2002., Methods: Survival rates were analysed according to period of diagnosis and tumour laterality., Results: Survival was calculated by calendar period of diagnosis, 1963-1982 and 1983-2002. For both unilateral and bilateral retinoblastoma, survival improved between the two periods. The survival curves for the two periods were significantly different: for unilateral retinoblastoma p<0.00001, for bilateral p<0.01. For unilateral cases, the estimated 5-year survival rates rose from 85% for those diagnosed in 1963-1967 to 97% for those diagnosed in 1998-2002. The equivalent rates for bilateral cases were 88% and 100%., Conclusion: Survival rates were already high at the start of the study period. They increased with changes in treatment regimens.

Aim: This paper describes the epidemiology and family history status of 1601 children with retinoblastoma in Great Britain diagnosed 1963-2002 and summarises the practical consequences for diagnosis and counselling of developments in molecular genetics., Methods: Incidence rates were analysed according to year of diagnosis and tumour laterality. Cases were classified as heritable or non-heritable on the basis of laterality and family history of the disease., Results: There were 998 unilateral cases, 581 bilateral and 22 of unknown laterality. Bilateral cases tended to be diagnosed at a younger age than unilateral. All bilateral cases are regarded as heritable, and 35% had a family history of the disease. 7% of the unilateral cases had a family history and are therefore heritable. Thus, at least (41%) of our cases are heritable. This is an underestimate, since these data on family history are incomplete. For unilateral cases aged below 1 year, the reported incidence rate increased significantly (p<0.0001) by about 2.5% per year; for the age group 1-4 years, the average increase was about 0.5% per year (not significant).

Aims: To evaluate rates of vitreous relapse among retinoblastoma patients treated with primary chemotherapy and assess diode laser as a potential risk factor for relapse., Methods: Retrospective review of all patients treated with primary chemotherapy at a large ocular oncology centre. Eyes that developed vitreous relapse were coded with regard to Reese-Ellsworth Group, laterality, time to relapse, type of relapse (vitreous base or non-vitreous base relapse), treatments used (including adjuvant diode laser), and ocular preservation. Individual tumour foci treated with laser hyperthermia were also coded for laser parameters including power settings, number of treatments, and concomitant administration of systemic chemotherapy (chemothermotherapy)., Results: 15 of 106 eyes (14.15%) developed vitreous relapse over a 6 year period. Mean time to relapse was 7.2 months after chemotherapy was completed. Five cases (33%) were of the vitreous base variety. Ocular salvage was attempted in 11 cases using a variety of methods; one patient was lost to follow up. Six of the remaining 10 eyes (60%) were salvaged. Eight of 38 eyes (21%) treated with systemic chemotherapy and laser hyperthermia developed vitreous relapse compared with seven of 68 eyes (10%) treated with primary chemotherapy alone (p<0.005). Laser settings, number of hyperthermia treatments, and the concomitant use of systemic chemotherapy (chemothermotherapy) were not associated with higher rates of vitreous relapse., Conclusion: Nearly one in seven eyes with retinoblastoma treated with primary chemotherapy may develop vitreous relapse. The administration of diode laser hyperthermia appears to increase this risk. Despite additional therapy a number of these eyes succumb to enucleation.

Based on 2283 cases of retinoblastoma diagnosed in children aged 0-14 years, incidence and survival in Europe during the period 1978-1997 are described. Data were provided to the Automated Childhood Cancer Information System (ACCIS) from 60 paediatric and general cancer registries. During 1988-1997, the cumulative incidence of retinoblastoma in the ACCIS regions was found to be between 44.2 and 67.9 per million births. The highest incidence was seen in the first year of life. The age-standardised (World standard) incidence rate for the age-range 0-14 years was 4.1 per million. Approximately one-third of cases had bilateral tumours. Overall incidence increased over the period 1978-1997 by 1% per year, as derived from a model adjusted for sex, age group and type of registry (general or paediatric). The 5-year survival rate improved from 89% to 95% during the period covered by the study. This improvement was seen in both unilateral and bilateral cases but was significant only for the unilateral tumours. Survival was lower in the East region, although smaller differences were also observed between the other four regions (British Isles, North, South and West). Availability and quality of registration data on retinoblastoma need to be improved for effective evaluation of incidence and survival.

Aims: To quantify the rates of eye preservation and patient survival, local tumour relapse and recurrence, and development of new tumours in the remaining eye of children with bilateral retinoblastoma with one eye already enucleated. Also, in the same children, to describe the types of primary and secondary treatment procedures, and to define the anatomical outcome., Methods: This is a retrospective observational case series report. The study participants consisted of 107 patients with bilateral retinoblastoma with one eye enucleated within 1 month of baseline examination and had their remaining eye treated conservatively. The main outcome measure were: primary treatment failures, new tumours, enucleation of the only eye, death, remission, and anatomical outcomes (retinal detachment, vitreous haemorrhage, and cataract)., Results: The median age at diagnosis was 8.4 (range 0.2-44, SD 10.1) months with a median ophthalmic follow up of 44.3 (8.1-114, SD 10.1) months. In 22 of the 107 patients (21%) the treated eye was in Reese Ellsworth groups I or II and in the remaining 85 (79%) in groups III-V at diagnosis. The primary treatment was cryotherapy in 14% (15/107) of eyes, radioactive plaque brachytherapy in 3.7% (4/107), and chemotherapy in 10% (11/107). It was lens sparing radiotherapy in 37% (40/107), whole eye radiotherapy in 29% (31/107), combined radiotherapy and chemotherapy in 2.8% (3/107), chemothermotherapy in 0.9% (1/107), and combined focal therapy in 1.8% (2/107). The primary treatment failed to achieve local tumour control during the follow up period in 37% (40/107) of eyes. In 17 eyes failure was due to inadequate control of the presenting tumour, in 16 to development of a new tumour, and in eight eyes to a combination of both. 35 (88%) of the 40 failures were managed by secondary conservative treatment and the remaining five were treated by enucleation of the only eye. There were eight (7.4%) deaths and the 3 year survival rate was 93% (100/108). Anatomical results included vitreous haemorrhage in four cases, tractional retinal detachment also in four cases, and 24 children required cataract surgery., Conclusions: Aggressive conservative treatment achieved a good rate of globe salvage without impairing survival.

Forty-nine primary retinoblastoma (Rb) tumors were analyzed by the use of comparative genomic hybridization (CGH), and clinical/histological correlations were performed. Adverse histological factors were present in 13 patients. Chromosomal imbalance was a frequent phenomenon, seen in 96% of the tumors. Gain of 6p represented the most frequent event (69% of the tumors), whereas +1q was observed in 57%, confirming that these abnormalities are key secondary events in retinoblastoma tumor progression. Loss of 13q and 16 was significantly associated with tumors displaying adverse histo-prognostic factors, whereas -16q was significantly associated with tumors without adverse features. In three patients who developed an extra-ocular relapse, the tumors showed -13q and 2/3 had -5q, suggesting that these abnormalities may be associated with metastasis. Children >or= 36 months of age at enucleation tended to have more CGH abnormalities per tumor than children < 12 months (median numbers 11 vs. 3). In addition, +1q, +13q, -16, and -16q were more frequent in children with an older age at enucleation. Identical CGH changes were found in both tumors from one patient with bilateral tumors, suggesting a common origin. It is possible that tumors displaying loss of 13q and 5q indicate those patients who may suffer an adverse outcome and who would require alternative or more intensive therapy. CGH analysis on larger cohorts and in prospective clinical trials will be invaluable in determining whether a genetic classification of retinoblastoma represents a reliable measure of prognosis., (Copyright 2003 Wiley-Liss, Inc.)

Twenty-five primary retinoblastoma tumours were analysed by real-time quantitative polymerase chain reaction to determine the genomic copy number of the N-MYC gene (2p24) relative to the copy number for REL, B2M, ALB, AF10 and MLL. Twenty-one of these tumours were shown by Comparative Genomic Hybridization to contain variable copy number increases of chromosomal material mapping to 2p. High level amplification (>30-fold) of N-MYC was found in three tumours, none of which showed adverse histological features and all patients are surviving at between 54 and 108 months post enucleation. Furthermore, the three tumours associated with metastasis and adverse patient outcome showed normal N-MYC copy number. Although high level amplification of N-MYC is an unfavourable prognostic indicator in neuroblastoma, these data show no evidence of a correlation between amplification of N-MYC and adverse outcome in retinoblastoma.

Aims: To evaluate how tumour size, retinal location, and patient age affect the outcome of retinoblastoma foci treated with chemotherapy., Methods: Retrospective review of retinoblastoma foci treated with primary chemotherapy alone. Individual tumours were coded with regard to their largest basal diameter, location within the eye (macula, macula to equator, equator to ora serrata), and patient's age at diagnosis. Successfully treated tumours required no further intervention while those requiring additional treatment were coded as failures., Results: 56 (72%) tumours responded successfully to chemotherapy alone while 22 (28%) required additional therapy. 26 of 31 macular tumours (84%) and 30 of 47 extramacular tumours (64%) responded to chemotherapy (p <0.060). Relative to size, 46 of 60 tumours (77%) greater than 2 mm in basal diameter were successfully treated with chemotherapy, while only 10 of 18 tumours (56%) less than or equal to 2 mm responded (p <0.088). Among the eight tumour foci diagnosed in children less than 2 months of age, five (63%) failed to respond to chemotherapy alone (p <0.032)., Conclusion: Retinoblastoma is more likely to respond to primary chemotherapy if it is located in the macula and if the patient is older than 2 months of age. Tumours measuring less than 2 mm in diameter may be less responsive to this treatment.

Background: Delay in diagnosis of retinoblastoma causes considerable parental distress; however, the primary healthcare professional (PHP) may have difficulty detecting the most common presenting symptom-leucocoria. Alternatively, the PHP may not appreciate that retinoblastoma is the pathology underlying more common ocular symptoms in infants and young children., Method: The parents of 100 recently diagnosed patients with retinoblastoma were interviewed to establish the extent of diagnostic delay, ascertain any associated risk factors, and to determine whether or not delay influenced treatment outcome., Results: Although nearly 50% of patients were referred to an ophthalmologist within 1 week of first consulting a PHP, one quarter waited more than 8 weeks. There was a significantly increased risk of diagnostic delay in younger patients, those presenting with squint rather than leucocoria, and those first presenting to a health visitor rather than to a general practitioner. The risk of local tumour invasion was significantly increased by diagnostic delay. Treatment with primary enucleation was not increased by diagnostic delay. There were no deaths during the study period., Conclusion: Primary healthcare professionals require education about the importance of ocular symptoms, especially squint, in paediatric patients.

Objective: The purpose of the study is to describe results of a new treatment for retinoblastoma vitreous base seeding., Design: The study design was a retrospective review of patients treated at an ocular oncology referral center., Participants: Five eyes of five patients with vitreous base seeding that occurred after previous external beam radiation therapy were treated between October 1987 and December 1994., Intervention: A customized plaque made from iridium-192/platinum wire was placed to deliver 4000 cGy to the tumor apex along its entire length and systemic chemotherapy (consisting of carboplatin, vincristine, and etoposide) was given., Main Outcome Measures: Eye preservation and tumor control were measured., Results: Vitreous base seeding was controlled completely and the eye preserved in four of the five treated eyes with an average follow-up of 26.2 months., Conclusions: The combination of a customized iridium-192 plaque and systemic chemotherapy is an effective means of treating vitreous base seeding of retinoblastoma.

The RB1 gene mutation was investigated in a child with ectopic intracranial retinoblastoma using DNA obtained from both the pineal and retinal tumours of the patient. A nonsense mutation in exon 17 (codon 556) of the RB1 gene was found to be present homozygously in both the retinal and the pineal tumours. The same mutation was present heterozygously in the DNA from the constitutional cells of the patient, proving it to be of germline origin. The initial mutation was shown to have occurred in the paternally derived RB1 allele. The mutation is in an area of the gene that encodes the protein-binding region known as the 'pocket' region and has been detected in other cases of retinoblastoma.

Objective: To determine the visual anatomical results and survival after combined chemotherapy and whole eye radiotherapy for patients with bilateral Reese-Ellsworth group V retinoblastoma., Setting: A national referral center for retinoblastoma., Patients: Fourteen patients with bilateral Reese-Ellsworth group V retinoblastoma seen between March 1, 1989, and April 30, 1995, were treated., Interventions: Patients were treated with chemotherapy (using carboplatin, etoposide, and vincristine) and whole eye radiotherapy (40-44 Gy in 20-22 equivalent fractions). A medical record review was performed to determine outcomes., Main Outcome Measures: Survival, eye preservation rate, and visual acuity., Results: Two patients died, 1 from a primitive neuroectodermal tumor and the other from the meningeal spread of retinoblastoma. Four eyes were enucleated primarily because of severe disease at presentation. Of the remaining 20 eyes, 6 required enucleation. The disease recurred in 4 of those patients, and neovascular glaucoma developed in 2 patients. Of the 12 surviving children, 5 have a visual acuity better than l/60 in at least 1 eye., Conclusion: Although most of the treated group V eyes could be salvaged with chemotherapy plus radiotherapy, the resultant visual acuity was often poor.

Chemotherapy without radiation has not controlled most intraocular retinoblastoma, perhaps because of the common high expression of multidrug resistance P-glycoprotein that we found in retinoblastoma. Cyclosporin blocks P-glycoprotein-induced efflux of vincristine and teniposide in vitro, and possibly modulates responses to carboplatin. To avoid eye irradiation in bilateral retinoblastoma patients with RB1 germline mutations, which incurs a high second malignancy rate, we added cyclosporin A to a vincristine-teniposide-carboplatin protocol and consolidated chemotherapy responses with focal therapy. We scored patients requiring irradiation, enucleation, or focal ablation of central vision as failures. In 21 study patients, the overall relapse-free rate at a median follow-up of 3.3 years was 76%, with a rate of 92% for newly diagnosed and 50% for previously treated, relapsed retinoblastoma. Our results for the most unfavorable tumors with vitreous seeds (86% at 3.5 years) are better than published success rates of irradiation for similar tumors, or irradiation with the same chemotherapy without cyclosporin (45% at 2. 6 years). These results also exceeded our historic success rate with similar chemotherapy without cyclosporin, focal therapy, and/or radiation in 19 equivalently poor-risk patients (relapse-free rate 37% at a median follow-up of 5.6 years, P = 0.032), 16 of whom were previously untreated (relapse-free rate also 37%, P = 0.012). A better outcome occurred with higher cyclosporin blood levels and projected tissue exposure. Cyclosporin did not enhance the usual chemotoxicity. This clinical study suggests that cyclosporin improves the long-term response of retinoblastoma to chemotherapy, possibly by more than one mechanism.

Two children presenting with sporadic unilateral retinoblastoma and exhibiting a high degree of chromosome breakage were noted to have unusual facies, microcephaly and abnormal skin pigmentation. In the first child the pattern of both spontaneous and mitomycin-C-induced chromosome breakage was characteristic of Fanconi's anaemia although the degree of breakage was extreme. She also exhibited a striking increase in X-ray-induced chromosomal damage in G0 lymphocytes as measured by dicentric formation and increase in chromatid-type aberrations. She had a number of typical clinical features, including cafe-au-lait patches and abnormalities involving the kidney; however, she demonstrated neither the hypoplasia of radius and thumb nor the typical aplastic phase of this disorder. At age 22 months the child became anaemic with trilineage myelodysplasia, which was rapidly followed by the development of acute myeloblastic leukaemia. The early onset (at age 4 months) of retinoblastoma may have been associated with the underlying genomic instability. The second child exhibited a pattern of chromosome breakage characteristic of Bloom's syndrome, in addition to a moderate increase in damage induced by mytomycin-C. She had the typical stunted growth and malar hypoplasia of Bloom's syndrome although she did not demonstrate the frequently described erythematous 'butterfly rash' Although patients with Fanconi's anaemia and Bloom's syndrome are recognised to be at an increased risk of cancer, retinoblastoma has not previously been described in patients with either condition. We suggest that underlying recessive chromosome breakage syndromes may be underdiagnosed in paediatric cancer patients, with important implications for prognosis and genetic counselling.

A retrospective analysis has been performed of the results of external beam radiotherapy for retinoblastoma using a whole eye technique. Local tumour control has been assessed in a consecutive series of 175 eyes in 142 children all of whom received external beam radiotherapy as the primary treatment for retinoblastoma. Follow up ranged from 2 to 17 years (median 9 years). Tumour control rates have been analysed with respect to the Reese Ellsworth classification and the series includes eyes in groups I to V. Focal salvage therapy was given for persistent, recurrent, or new tumours after radiotherapy. Following whole eye radiotherapy alone, the overall ocular cure rate was 57%, though with salvage therapy 80% of eyes could be preserved.

A retrospective analysis is presented of the results of external beam radiotherapy for retinoblastoma utilising an accurate lens sparing technique. Local tumour control has been assessed in a consecutive series of 67 eyes in 53 children all of whom received external beam radiotherapy as the primary treatment of retinoblastoma. Follow up ranged from 12 to 82 months (median 35 months) with 76% of the children followed for more than 2 years. Tumour control rates have been analysed with respect to the Reese-Ellsworth classification. The role of adjuvant and salvage focal therapy is emphasised. Following lens sparing radiotherapy with prior adjuvant treatment of anterior tumours, where appropriate, the overall ocular cure rate was 72%. With salvage therapy of persistent, recurrent, or new tumours, 93% of eyes could be preserved in this series which includes mainly eyes classified in Reese-Ellsworth groups I-III. These results compare favourably with those of whole eye external beam radiotherapy for comparable tumours, and with those of lens and anterior segment sparing using other techniques. They were achieved without the ocular morbidity associated with whole eye external beam radiotherapy.

A retrospective analysis has been conducted of regression patterns following treatment of retinoblastoma by external beam irradiation. There were 180 tumours in 105 eyes of 83 patients. Type I regression was found to be the commonest pattern and occurred in 50% of cases. Initial tumour size was found to be the only statistically significant determinant of regression pattern (p < 0.01). Thirteen tumours (7%) recurred within a median interval to recurrence of 12 months. All recurrences occurred within 40 months of completion of treatment and none occurred after age 4 years. No tumour less than 6 mm in diameter recurred. Although 10 out of 13 recurrences were of Type I, Cox model regression analysis showed initial tumour size to be the only independent predictor of recurrence (p < 0.01).

Five children with an orbital recurrence of retinoblastoma have been successfully treated by a combination of excision biopsy of the tumour mass, radical orbital radiotherapy, and systemic chemotherapy. Nine previous children, consecutive with the five presented here, died from disseminated retinoblastoma after failure of earlier treatment programmes for orbital recurrence. An aggressive therapeutic approach is justified by this improvement in survival.

123I metaiodobenzylguanidine (MIBG) is a radiopharmaceutical used for imaging neural crest tumours. The possibility of using 123I MIBG for imaging retinoblastomas has been assessed in this pilot study. Ten patients were studied, nine with clinically and histologically proved retinoblastomas and one with Coats's disease. 123I MIBG scintigraphy correctly identified the neoplasm in eight patients but gave a negative result in two, one of whom had Coats's disease and the other a retinoblastoma which proved to be extensively necrotic on histological examination. These preliminary results suggest that 123I MIBG scintigraphy may have a role in differentiating retinoblastomas from lesions that simulate them.

Radioiodinated metaiodobenzylguanidine (MIBG) has been used for diagnostic purposes to image neural crest tumors. We report the uptake of 123I MIBG in a child with ectopic intracranial retinoblastoma. It is felt that 123I MIBG scintigraphy may have a role in detecting occult metastatic disease in these patients.

A register of retinoblastoma is being compiled with the aim of complete ascertainment of all cases with a recorded diagnosis of retinoblastoma in the United Kingdom. Sources of ascertainment include patients seen at St Bartholomew's and Moorfields Eye Hospitals, cases recorded in regional cancer registries, and pathology reports. Ascertainment of the Hospital series is complete, but that of the rest of the country is still incomplete. Comparison between the proportions of bilateral and unilateral cases in an age cohort in the Hospital series and the country as a whole shows that the Hospital series is biased towards an excess of bilateral cases.

Twelve out of a series of 630 children with retinoblastoma, treated in the ocular oncology units at St Bartholomew's and Moorfields Eye Hospitals during the past 30 years, have developed ectopic intracranial retinoblastoma. The ectopic tumour occurred in the pineal region in eight children and in the suprasellar region in four. Ten patients had bilateral retinoblastoma, one unilateral disease, and one child presented with an isolated suprasellar tumour but no evidence of retinal disease. The interval from the initial diagnosis of retinoblastoma to the development of ectopic intracranial disease ranged from 4 to 70 months, median 34 months. Methods of treatment for the ectopic tumour varied, but all 12 children died with a median survival of only 8 months following the diagnosis of ectopic retinoblastoma. Subsequent spread of tumour to other sites within the central nervous system proved to be the most frequent cause of death. Ectopic intracranial retinoblastoma is a potentially curable neoplasm, but it requires adequate therapy to the whole neuraxis as well as high dose equivalent radiotherapy to the primary tumour.

Forty years of research into retinoblastoma has seen wide-ranging changes in our knowledge of the histogenesis of this childhood tumour and in the treatment of the disease. These changes, and some of the more recent developments in the molecular biology of this tumour are reviewed.

Patients with retinoblastoma diagnosed from 1969 to 1980 have been followed up for periods of up to 17 years. Data from a previous study of patients diagnosed from 1962 to 1968 have been included for analysis of incidence and second primary tumours, and for study of trends in treatment. The registration rate in Britain (which may be about 10% less than the true incidence) is about one in 23,000 live births, approximately 40% of cases being known to be genetic. There is no apparent trend in incidence during the period covered by these two studies. The three-year survival rate in 88%. Patients with bilateral tumours have a better survival rate than those with unilateral tumours for the first few years, but their long-term survival rate is worse because of later deaths from ectopic intracranial retinoblastoma or second primary neoplasms. Older children tend to have a worse prognosis, which is related to the fact that their tumours are diagnosed at a more advanced stage. There is a significantly higher survival rate for boys than for girls; this is partly accounted for by difference in age and stage at diagnosis between the sexes. Children referred to units specialising in the treatment of retinoblastoma have a higher three-year survival rate than those treated at other hospitals. Comparing methods of treatment between the periods 1962-8 and 1969-80, we find there has been a trend towards more conservative treatment. The use of chemotherapy is now usually reserved for recurrences and metastases and for palliative treatment in terminal retinoblastoma.

In a series of 882 retinoblastoma patients, 384 known to have the genetic form of the disease and 498 others, 30 patients developed second primary neoplasms. The spectrum of these second neoplasms is discussed in relation to the forms of treatment used for the retinoblastoma. Cumulative incidence rates of second tumours in the whole series are 2.0% at 12 years after diagnosis and 4.2% after 18 years. For patients with the genetic form of retinoblastoma the cumulative incidence rate after 18 years is 8.4% for all second neoplasms and 6.0% for osteosarcomas alone. The inherent risk among survivors from genetic retinoblastoma of developing an osteosarcoma, excluding all possible effects of treatment, is estimated to be 2.2% after 18 years. Within the field of radiation treatment the cumulative incidence rate for all second neoplasms after 18 years is 6.6% and for osteosarcomas alone 3.7%. There is some evidence that patients with genetic retinoblastoma are particularly sensitive to the carcinogenic effects of radiation. The results also suggest that the use of cyclophosphamide may increase the risk of second primary neoplasms in patients with genetic retinoblastoma. The incidence rates of second primary neoplasms in retinoblastoma survivors reported here are lower than those quoted for previously published series. Evidence from this and other papers strongly suggests an association between retinoblastoma and malignant melanoma.

Eleven children with metastatic retinoblastoma diagnosed during the period 1970-1984 were treated with chemotherapy. Short-term complete responses were observed in three children treated with a four-drug combination which included cisplatinum, and in one child treated with vincristine and cyclophosphamide. The median duration of survival of the 11 children receiving chemotherapy was nine months, whilst the median survival of 13 children with metastatic retinoblastoma who were not given chemotherapy was only 2.3 months (p = 0.06). This suggests that retinoblastoma is a chemosensitive tumour and therefore adjuvant chemotherapy may have a role in children with retinoblastoma who at diagnosis are thought to be at high risk of developing metastatic disease.