Treatment of retinoblastoma patients with chemoreduction plus local therapy: experience of the AC Camargo Hospital, Brazil

Effect of Intravenous Chemotherapy Regimen on Globe Salvage Success Rates for Retinoblastoma Based on Disease Class-A Meta-Analysis

Simple Summary

Intravenous chemoreduction (IVCRD) has been the standard of care for treatment of retinoblastoma (RB). Since survival rates exceed 95–98%, the goals of treatment have now shifted to emphasize eye salvage and vision preservation in addition to patient survival. Consequently, there has been a shift towards combining standard IVCRD with intravitreal chemotherapy or altogether replacing IVCRD with intra-arterial chemotherapy. As more data from intravitreal chemotherapy and intra-arterial chemotherapy are being published, there are claims of improved globe salvage rates resulting in more widespread use of these newer treatment modalities. However, there are no published randomized controlled trials comparing these to IVCRD head-to-head. To evaluate the relative efficacy of these new therapies, it is critical to determine the true success rates of IVCRD regimens alone. Therefore, it is both timely and essential to determine the baseline IVCRD success rates so that an evidence-based assessment of new and emerging therapies can be determined.

Abstract

To evaluate the relative efficacy of novel retinoblastoma treatments, eye classification-specific success rates for current standard-of-care intravenous chemotherapy regimens must be known. This meta-analysis included studies if: (1) patients received intravenous chemotherapy for retinoblastoma, (2) globe salvage data was reported, (3) only intravenous chemoreduction (with/without local consolidation) was used. The outcome measure was globe salvage success without need for salvage radiotherapy, subdivided by disease classification and chemotherapy regimen. Data from 27 studies (1483 eyes) were pooled. By Reese–Ellsworth classification, globe salvage rates were 85% (95%CI:73–92%) for Group I, 78% (95%CI:70–85%) for Group II, 68% (95%CI:56–78%) for Group III, 47% (95%CI:34–60%) for Group IV, and 35% (95%CI:26–45%) for Group V (Va: 35% [95%CI:21–54%]; Vb: 42% [95%CI:29–56%]; those without sub-classification: 31% [95%CI:19–47%]). By International Classification, globe salvage rates were 93% (95%CI:80–97%) for Group A, 83% (95%CI:73–89%) for Group B, 73% (95%CI:54–86%) for Group C, 40% (95%CI:31–51%) for Group D, and 19% (95%CI:5–50%) for Group E. Standard carboplatin-etoposide-vincristine out-performed two-drug regimens (odds ratio (OR) = 1.9 (95%CI:1.3–3.0) for Groups I-IV and OR = 2.1 (95%CI:1.3–3.4) for Group V; p = 0.002 for each). For eyes with diffuse vitreous seeds (Vb), an enhanced regimen out-performed standard chemotherapy (OR = 2.4 [95%CI:1.3–4.7]; p = 0.004). In conclusion, two-drug regimens were less effective for all eyes, whereas enhanced regimens were more effective for eyes with vitreous seeds. Novel therapies can now be compared to these baseline globe salvage rates.

Conservative management of retinoblastoma: Challenging orthodoxy without compromising the state of metastatic grace. "Alive, with good vision and no comorbidity"

Retinoblastoma is lethal by metastasis if left untreated, so the primary goal of therapy is to preserve life, with ocular survival, visual preservation and quality of life as secondary aims. Historically, enucleation was the first successful therapeutic approach to decrease mortality, followed over 100 years ago by the first eye salvage attempts with radiotherapy. This led to the empiric delineation of a window for conservative management subject to a "state of metastatic grace" never to be violated. Over the last two decades, conservative management of retinoblastoma witnessed an impressive acceleration of improvements, culminating in two major paradigm shifts in therapeutic strategy. Firstly, the introduction of systemic chemotherapy and focal treatments in the late 1990s enabled radiotherapy to be progressively abandoned. Around 10 years later, the advent of chemotherapy in situ, with the capitalization of new routes of targeted drug delivery, namely intra-arterial, intravitreal and now intracameral injections, allowed significant increase in eye preservation rate, definitive eradication of radiotherapy and reduction of systemic chemotherapy. Here we intend to review the relevant knowledge susceptible to improve the conservative management of retinoblastoma in compliance with the "state of metastatic grace", with particular attention to (i) reviewing how new imaging modalities impact the frontiers of conservative management, (ii) dissecting retinoblastoma genesis, growth patterns, and intraocular routes of tumor propagation, (iii) assessing major therapeutic changes and trends, (iv) proposing a classification of relapsing retinoblastoma, (v) examining treatable/preventable disease-related or treatment-induced complications, and (vi) appraising new therapeutic targets and concepts, as well as liquid biopsy potentiality.

Feasibility and results of an intraarterial chemotherapy program for the conservative treatment of retinoblastoma in Argentina

BACKGROUND

The feasibility and results of intraarterial chemotherapy, also termed ophthalmic artery chemosurgery (OAC), for retinoblastoma in less developed countries have seldom been reported.

PROCEDURE

A retrospective evaluation of a program of OAC in Argentina from 2010 to 2015.

RESULTS

Ninety-seven eyes from 81 patients (61 bilateral) were analyzed. In 35 eyes, OAC was given as primary therapy and in 62 it was used for the treatment of tumors with partial response or those relapsing after systemic chemoreduction with focal therapy or external-beam radiotherapy. Twenty-two primarily treated eyes had group D and 13 groups B/C. A total of 400 procedures were carried out. Chemotherapy used included combinations of melphalan, carboplatin, and topotecan. There was no mortality associated with OAC. Toxicity included fever and neutropenia in five (1.25%), hypotension and bradycardia during anesthesia in two and femoral thrombosis in one, eyelid edema in nine, and neutropenia or thrombocytopenia in 28 cycles. With a median follow-up of 48.7 months (range 12-79), the 3-year probability of event-free survival (pEFS) (enucleation and/or radiotherapy were considered events) was comparable for patients who received first-line therapy and those treated at relapse (0.65 vs. 0.63, P = 0.5). In the former, the pEFS was 0.91 and 0.43 for groups B/C and D, respectively (P = 0.01). Two patients died of extraocular dissemination after refusal of enucleation.

CONCLUSIONS

OAC was feasible with low toxicity. pEFS improved in all groups compared to the previous experience with systemic chemotherapy reducing the use of radiotherapy. The overall mortality associated with OAC is comparable to our previous experience with systemic chemoreduction.

Intravitreal chemotherapy in retinoblastoma: expanded use beyond intravitreal seeds

BACKGROUND/AIMS

Ophthalmic artery chemosurgery (OAC) has changed the face of retinoblastoma treatment and led to a higher rate of globe salvage. The introduction of intravitreal chemotherapy (IVitC) has further enhanced globe salvage with increased success in treatment of intravitreal seeds. Our group has seen success at treating non-vitreous disease that is refractory to OAC using IVitC. This study was undertaken to quantify and report on this success.

METHODS

A retrospective review was used to identify patients treated with IVitC for indications other than vitreous seeds from two centres. The indication, prior and concurrent treatment, response time and duration of treatment were documented. Kaplan-Meier estimates were used to evaluate ocular and recurrence-free survival. Ocular toxicity was evaluated using the 30 Hz flicker electroretinogram (ERG). Continuous and categorical variables were compared with Student's t-test and χ² test, respectively.

RESULTS

Fifty-six eyes from 52 retinoblastoma patients were identified. There were no disease-related or treatment-related deaths. One patient developed a second primary malignancy (pinealoblastoma) and subsequent leptomeningeal spread. Ninety-eight per cent of the eyes showed clinical regression. Recurrence was seen in 14.3%. Of the recurrences, five occurred in retinal tumours and three in subretinal seeds. The Kaplan-Meier estimated risk of recurrence in all patients treated was 83.5% (95% CI 7.9 to 14.1) at 10 months. The mean change in ERG over treatment course was -17.7 μV.

CONCLUSIONS

Intravitreal chemotherapy is successful for the treatment of subretinal seeds and recurrent retinal tumours and could be considered as adjunctive therapy in globe-sparing treatment of retinoblastoma.

Integrin-linked kinase regulates senescence in an Rb-dependent manner in cancer cell lines

Anti-integrin-linked kinase (ILK) therapies result in aberrant mitosis including altered mitotic spindle organization, centrosome declustering and mitotic arrest. In contrast to cells that expressed the retinoblastoma tumor suppressor protein Rb, we have shown that in retinoblastoma cell lines that do not express Rb, anti-ILK therapies induced aberrant mitosis that led to the accumulation of temporarily viable multinucleated cells. The present work was undertaken to: 1) determine the ultimate fate of cells that had survived anti-ILK therapies and 2) determine whether or not Rb expression altered the outcome of these cells. Our data indicate that ILK, a chemotherapy drug target is expressed in both well-differentiated, Rb-negative and relatively undifferentiated, Rb-positive retinoblastoma tissue. We show that small molecule targeting of ILK in Rb-positive and Rb-deficient cancer cells results in increased centrosomal declustering, aberrant mitotic spindle formation and multinucleation. However, anti-ILK therapies in vitro have different outcomes in retinoblastoma and glioblastoma cell lines that depend on Rb expression. TUNEL labeling and propidium iodide FACS analysis indicate that Rb-positive cells exposed to anti-ILK therapies are more susceptible to apoptosis and senescence than their Rb-deficient counterparts wherein aberrant mitosis induced by anti-ILK therapies exhibit mitotic arrest instead. These studies are the first to show a role for ILK in chemotherapy-induced senescence in Rb-positive cancer lines. Taken together these results indicate that the oncosuppressive outcomes for anti-ILK therapies in vitro, depend on the expression of the tumor suppressor Rb, a known G1 checkpoint and senescence regulator.

Disparities in Retinoblastoma Presentation, Treatment, and Outcomes in Developed and Less-Developed Countries

Retinoblastoma (RB) is the most common intraocular malignancy in children. In the past century, RB survival rates in developed countries (DCs) have improved from <5% to as high as 99%. In contrast, in less developed countries (LDCs) where the tumor burden is greatest, survival rates remain poor, with some countries reporting survival rates as low as 0-5%. In addition, there are disparities between DCs and LDCs in RB presentation, treatment modalities, and prognosis. These disparities are due to many underlying causes, including delays in diagnosis, access to medical care, patient and physician familiarity with the disease, availability and cost of treatment, and patient acceptance of enucleation. It is our belief that attempts to extend the improvements in prognosis achieved in DCs to various LDCs must be culturally sensitive and tailored to each country's specific challenges, and thus, a "one-size-fits-all" approach to improving patient outcomes in LDCs is unlikely to work well. We discuss several culturally sensitive approaches that have been successfully implemented in various LDCs, including those that make use of telemedicine and "twinning" with centers of excellence around the world.

Impact of chemoreduction for conservative therapy for retinoblastoma in Argentina

BACKGROUND

Few studies were reported from developing countries regarding patient outcome and ocular survival in children with bilateral retinoblastoma treated with chemoreduction compared to external beam radiotherapy (EBRT).

PROCEDURE

We undertook a retrospective study of three treatment eras: (1) (1988-1995) n = 68 when EBRT was used as primary conservative therapy; (2) (1995-2003) n = 46 when carboplatin-based systemic chemoreduction was introduced and (3) (2003-2009) (n = 83) when additional periocular chemotherapy was added for advanced tumors and pre-enucleation chemotherapy was given for those with massive buphthalmia.

RESULTS

The probability of 5-year disease-free survival was 0.94 (95% confidence interval [CI] 0.91-0.98%) without significant differences among the three eras. Chemoreduction reduced the use of EBRT from 84.6% to 68.7% in eras 1 and 3, respectively (P = 0.008), which was more evident in cases with less advanced disease. Chemoreduction also significantly improved the 5-year probability of preservation of eyes with advanced disease from 0.13 (95% CI 0.04-0.27) during era 1 to 0.49 (95% CI 0.34-0.62) in era 3 (P < 0.0001). Chemoreduction was not associated with changes in the probability of extraocular relapse, which was reduced after the introduction of pre-enucleation chemotherapy. Second malignancies occurred in nine cases, acute myeloid leukemia being the most fatal one. Trilateral retinoblastoma occurred in three cases and all of them had been exposed to chemotherapy.

CONCLUSIONS

Chemoreduction reduced the need for EBRT in eyes with less advanced disease and improved the preservation of eyes with advanced disease while its effects on secondary malignancies or trilateral disease remain unclear.

[Retinoblastoma: preliminary results of national treatment protocol at Casablanca university medical center]

Retinoblastoma is the most frequent intraocular cancer, affecting almost exclusively children. We report prospective study results assessing the national protocol for retinoblastoma treatment in Morocco. Treatment included, depending on stage and laterality, primary chemotherapy either to facilitate enucleation or to make conservative treatment possible, postoperative chemotherapy, enucleation and conservative treatments such as transpupillary thermotherapy, thermochemotherapy and cryotherapy. Radiation was used in a few cases. Close supervision was performed until the age of 5. The incidence of retinoblastoma within the study period was 18 new cases per year in our department. Observations of 32 children were included in the study: 18 unilateral retinoblastomas (56%) and 14 bilateral retinoblastomas (44%), for a total of 46 eyes. Leucocoria was the most frequent presenting symptom (69%). Buphthalmia or proptosis were present in 47% of cases. The stage of retinoblastoma was V/D or E (Reese-Elsworth/ABC) in 69.5% of cases. Enucleation was necessary for 28 eyes. Transpupillary thermotherapy or thermochemotherapy were used for 13 eyes (11 children) and cryotherapy for 13 eyes (10 children). After an average follow-up period of 52 months, among 32 children, 4 died and 2 abandoned treatment. Ocular salvage rate was 85.7% (12 eyes out of 14, among which 11 without radiation). Retinoblastoma is a genetic tumor, which occurs in two forms: sporadic, always unilateral, and hereditary, often bilateral. The latter is the most challenging case. Current treatment protocols rely primarily on chemotherapy and local treatments. The future is oriented toward purely local treatments such as intra-arterial chemotherapy and intraocular chemotherapy.

Intra-arterial chemotherapy for retinoblastoma: a practical review

The use of chemotherapy for retinoblastoma constitutes a promising treatment strategy. Retinoblastoma is the most common eye cancer in the childhood.. Treatment depends on the laterality, intraocular location and tumor extension. Radiation therapy became an important element in the management of this type of injury risk of extraocular secondary tumor development. Eye salvage is mandatory when vision preserved. The current neuroendovascular techniques constitute a therapeutic tool for these tumors. We present a practical review of current concepts in the management of these tumors.

Survey on the management of orbital and intraocular tumors among oculofacial surgeons in the Asia-Pacific region

A web-based anonymous survey was performed to assess the common practices of oculofacial surgeons in the management of orbital and intraocular tumors in the Asia-Pacific region. The questionnaire comprised a series of questions covering controversial topics sent via email to 131 oculofacial surgeons across 14 countries in the Asia-Pacific region. A total response rate of 61.7 % was achieved from May to December 2012. The most common benign orbital tumor was cavernous hemangioma (39.6 %) and the most common malignant orbital tumor was lymphoma (85.7 %). 40 % of surgeons recommended orbital radiation, for which the most common indications were thyroid eye disease (70.0 %) and malignancy (30.0 %). The most common orbitotomy approach was lateral (79.2 %). Most surgeons (87.1 %) offered enucleation for retinoblastoma, but there was also a significant proportion that offered chemoreduction with transpupillary thermotherapy or cryotherapy (58.1 %). Fewer surgeons offered brachytherapy (16.1 %) and intra-arterial chemotherapy (6.5 %). When performing enucleation for retinoblastoma, 81.8 % of surgeons performed a primary orbital implant placement. The most preferred type of implant was silicone/acrylic (90.2, 90.2 and 87.8 % for elderly, adults and children, respectively). The majority of surgeons used donor sclera (57.5 %) or no wrapping material at all (32.5 %). Almost all surgeons (95.1 %) did not drill and peg the implant for motility. We report the results of the first survey of oculofacial surgeons in the Asia-Pacific region on the management of intraocular and orbital tumors. In comparison with previous surveys performed in the USA and the UK, we found the practice patterns of the Asia-Pacific surgeons to be comparable.

In human retinoblastoma Y79 cells okadaic acid-parthenolide co-treatment induces synergistic apoptotic effects, with PTEN as a key player

Retinoblastoma is the most common intraocular malignancy of childhood. In developing countries, treatment is limited, long-term survival rates are low and current chemotherapy causes significant morbidity to pediatric patients and significantly limits dosing. Therefore there is an urgent need to identify new therapeutic strategies to improve the clinical outcome of patients with retinoblastoma. Here, we investigated the effects of two natural compounds okadaic acid (OKA) and parthenolide (PN) on human retinoblastoma Y79 cells. For the first time we showed that OKA/PN combination at subtoxic doses induces potent synergistic apoptotic effects accompanied by lowering in p-Akt levels, increasing in the stabilized forms of p53 and potent decrease in pS166-Mdm2. We also showed the key involvement of PTEN which, after OKA/PN treatment, potently increased before p53, thus suggesting that p53 activation was under PTEN action. Moreover, after PTEN-knockdown p-Akt/ pS166Mdm2 increased over basal levels and p53 significantly lowered, while OKA/PN treatment failed both to lower p-Akt and pS166-Mdm2 and to increase p53 below/over their basal levels respectively. OKA/PN treatment potently increased ROS levels whereas decreased those of GSH. Reducing cellular GSH by l-butathionine-[S,R]-sulfoximine treatment significantly anticipated the cytotoxic effect exerted by OKA/PN. Furthermore, the effects of OKA/PN treatment on both GSH content and cell viability were less pronounced in PTEN silenced cells than in control cells. The results provide strong suggestion for combining a treatment approach that targets the PTEN/Akt/Mdm2/p53 pathway.

Intra-arterial chemotherapy is more effective than sequential periocular and intravenous chemotherapy as salvage treatment for relapsed retinoblastoma

BACKGROUND

Treatment of eyes with retinoblastoma failing systemic chemoreduction and external beam radiotherapy is seldom efficacious. This study compares the efficacy and toxicity of intra-arterial ophthalmic artery chemotherapy (IAO) to our historical cohort of sequential periocular and systemic chemotherapy in such patients.

PATIENTS AND METHODS

Eighteen eyes (15 consecutive patients) were retrospectively evaluated. Eight eyes received IAO for a median of four cycles (range: 2-9) including melphalan alone (n = 3) or after topotecan and carboplatin (n = 4) or topotecan and carboplatin without melphalan (n = 1). Ten eyes received a median of two cycles (range: 1-3) of periocular topotecan (n = 9) or carboplatin (n = 1) followed by intravenous topotecan and cyclophosphamide in three patients if at least stable disease was achieved. Both groups were comparable for disease extension and prior therapy.

RESULTS

No extraocular dissemination or second malignancy occurred and all patients are alive. The probability of enucleation-free eye survival at 12 months was 0.87 (95% CI: 0.42-0.97) for the IAO group, compared to 0.1 (95% CI: 0.06-0.35) for the periocular group (P < 0.01). Ocular toxicity was mild and similar in both groups (mostly mild orbital edema). Systemic toxicity was low for IAO and periocular injection, but children who received sequentially intravenous chemotherapy (n = 12 cycles) had five episodes of grade 4 neutropenia, three of which resulted in hospitalizations. No case in the IAO group presented these complications.

CONCLUSIONS

IAO is significantly superior to sequential periocular-intravenous topotecan-containing regimens in eyes with relapsed intraocular retinoblastoma with a more favorable toxicity profile.

SIOP-PODC recommendations for graduated-intensity treatment of retinoblastoma in developing countries

Retinoblastoma remains incurable in many regions of the world. The major obstacles to cure are delayed diagnosis, poor treatment compliance, and lack of evidence-based recommendations for clinical management. Although enucleation is curative for intraocular disease, in developing countries retinoblastoma is often diagnosed after the disease has disseminated beyond the eye. A SIOP-PODC committee generated guidelines for the clinical management of retinoblastoma in developing countries and developed a classification system based on the resources available in those settings. Recommendations are provided for staging and treatment of unilateral and bilateral retinoblastoma and counseling of families for whom compliance is an issue.

A clinical update and radiologic review of pediatric orbital and ocular tumors

While pediatric orbital tumors are most often managed in tertiary care centers, clinicians should be aware of the signs of intraocular and orbital neoplasms. In the pediatric population, a delay in diagnosis of orbital and intraocular lesions, even if benign, can lead to vision loss and deformity. Intraocular lesions reviewed are retinoblastoma, medulloepithelioma, and retinal astrocytic hamartoma. Orbital neoplasms reviewed are rhabdomyosarcoma, neuroblastoma metastases, optic pathway glioma, plexiform neurofibroma, leukemia, lymphoprolipherative disease, orbital inflammatory syndrome, dermoid and epidermoid inclusion cysts, and Langerhans' cell histiocytosis. Vascular lesions reviewed are infantile hemangioma and venous lymphatic malformation. In conjunction with clinical examination, high-resolution ophthalmic imaging and radiologic imaging play an important role in making a diagnosis and differentiating between benign and likely malignant processes. The radiologic imaging characteristics of these lesions will be discussed to facilitate prompt diagnosis and treatment. The current treatment modalities and management of tumors will also be reviewed.

Combined, sequential intravenous and intra-arterial chemotherapy (bridge chemotherapy) for young infants with retinoblastoma

Background

Intra-arterial (IA) chemotherapy has more risks of procedural complications in neonates and young infants. For these reasons, we have developed a strategy of bridge intravenous single agent chemotherapy to postpone IA chemotherapy in these children

Procedure

Neonates and young infants with retinoblastoma who required chemotherapy were treated with systemic carboplatin chemotherapy (18.7 mg/kg IV every 3–4 weeks) until they reached the age of 3 months and a weight of 6 Kg. If necessary, IA chemotherapy was subsequently performed at 4 weeks intervals. Efficacy was judged by tumor regression on ophthalmological examination. Retinal toxicity was judged by electroretinography.

Results

Eleven children (19 eyes) were treated. All patients are alive and no patient has developed metastatic disease or second malignancies (mean follow-up 27 months, range 9–46 months). Intravenous carboplatin (median 2 cycles, range 1–5) combined with cryotherapy and laser was given to all children. This was effective for five eyes, which did not require IA chemotherapy. IA chemotherapy was administered to 14 eyes (median 3.5 cycles per eye, range 1 to 6). No radiation therapy was required. The Kaplan Meier estimate of ocular radiation-free survival was 94.7% at one year (95% confidence interval 68.1–99.2%). One eye was enucleated due to tumor progression. ERG showed no deterioration of retinal function.

Conclusion

Bridge IV-IA chemotherapy was feasible and safe, and is a promising strategy to treat retinoblastoma in neonates and young infants.

Abnormal orbital growth in children submitted to enucleation for retinoblastoma treatment

Enucleation is typically performed for the treatment of advanced retinoblastoma in children. After enucleation, the orbit undergoes abnormal development. In this study, orbital asymmetry was calculated using computed tomography measurements obtained from patients who experienced enucleation for unilateral retinoblastoma. Influence factors analyzed included: type of treatment, use of orbital implants, and patient's age at diagnosis. A total of 42 children underwent enucleation with a mean follow-up period of 4.8 years. For 28 patients, treatment included enucleation alone, 14 patients received enucleation plus radiation therapy. Thirty patients kept orbital implants long term. The mean orbital volume asymmetry for treated versus contralateral orbits was 16.8%. Mean asymmetry in orbital volume was greater for patients who underwent enucleation combined to radiation therapy (23.7% vs. 13.3%, P=0.05) and for patients without long-term maintenance of the prosthetic implants (29.3% vs. 11.8%, P<0.01). In conclusion, orbital volume is abnormally affected in children after enucleation of 1 eye for the treatment of retinoblastoma, and computed tomography can precisely quantify the asymmetry that develops. Orbital implants improve volumetric growth after enucleation, with 2-fold greater orbital asymmetry achieved without an implant.

Evaluation of ototoxicity in children treated for retinoblastoma: preliminary results of a systematic audiological evaluation

BACKGROUND

The objective of this study was to identify the ocurrence of hearing loss in children treated for retinoblastoma using a multidisciplinary approach.

PATIENTS AND METHODS

Thirty-two children were evaluated pre- and post-treatment. Eleven children were treated exclusively with enucleation, fifteen with carboplatin and six with cisplatin. Otoacoustic emissions were performed with the ILO 88, before and after the treatment.

RESULTS

In our study we found 5 children (24%) with hearing loss among the 21 evaluated. However in the group of children treated with carboplatin (N=15), 1 case (6.6%) presented hearing loss, while among those treated with cisplatin (N=6) we found 4 cases (66.6%) with hearing loss (p=0.0114).

CONCLUSION

We concluded that patients who are treated with cisplatin are at risk for developing hearing loss.

Treatment with connexin 46 siRNA suppresses the growth of human Y79 retinoblastoma cell xenografts in vivo

Tumors with a hypoxic component, including human Y79 retinoblastoma cells, express a specific gap junction protein, Connexin 46 (Cx46), which is usually only found in naturally hypoxic tissues such as the differentiated lens. The aim of this study was to investigate if Cx46 downregulation would suppress Y79 tumor formation in vivo. Five-week old nude mice were subcutaneously implanted with human Y79 retinoblastoma cells and treated with intratumor siRNA injections of 30 μg Cx46 siRNA (n = 6), 30 μg non-silencing siRNA (n = 6), or no siRNA treatment (n = 6) every 2 days for a maximum of 10 treatments. Tumor volume (TV) was calculated from the recorded caliper measurements of length and width. Excised tumors were measured and weighed. Western blot analyses were performed to evaluate Cx46 and Cx43 expression in tumors which received Cx46 siRNA, non-silencing siRNA, or no siRNA treatment. Tumor histopathology was used to assess tumor features. Cx46 siRNA treated Y79 tumors had a reduced TV (287 mm(3) ± 77 mm(3)) when compared to the tumors of mice receiving the negative control siRNA (894 mm(3) ± 218 mm(3); P ≤ 0.03) or no siRNA (1068 mm(3) ± 192 mm(3); P ≤ 0.002). A 6-fold knockdown of Cx46 and a 3-fold rise in Cx43 protein expression was observed from western blots of tumors treated with Cx46 siRNA compared to mice treated with non-silencing siRNA. Knockdown of Cx46 with siRNA had an antitumor effect on human Y79 retinoblastoma tumors in the nude mouse model. The results suggest that anti-Cx46 therapy may be a potential target in the future treatment of retinoblastoma.

Strategies to manage retinoblastoma in developing countries

Survival of retinoblastoma is >90% in developed countries but there are significant differences with developing countries in stage at presentation, available treatment options, family compliance, and survival. In low-income countries (LICs), children present with advanced disease, and the reasons are socioeconomic and cultural. In middle-income countries (MICs), survival rates are better (>70%), but there is a high prevalence of microscopically disseminated extraocular disease. Programs for eye preservation have been developed, but toxicity-related mortality is higher. Although effective treatment of microscopically extraocular disease improved the outcome, worldwide survival will be increased only by earlier diagnosis and better treatment adherence.

Long term follow-up results of external beam radiotherapy as primary treatment for retinoblastoma

The authors reviewed their experiences of external beam radiotherapy (EBR) as an initial treatment in retinoblastoma patients to determine its long-term effect on subsequent tumor control and complications. A total of 32 eyes in 25 patients that underwent EBR for retinoblastoma were reviewed retrospectively. The patients consisted of 21 boys and 4 girls of median age at treatment of 7.1 months. Radiation doses ranged from 35 to 59.4 Gy. The 10-yr ocular and patient survivals were 75.4% and 92.3%, respectively. Nine of the 32 eyes progressed; 7 of these were enucleated and 2 were salvaged by focal treatment. According to the Reese-Ellsworth classification, 4 of 5 eyes of Group II, 13 of 16 Group III eyes, 2 of 4 Group IV eyes, and 5 of 7 Group V eyes were retained, and of the 32 eyes, 13 had visual acuity better than 20/200. Eleven patients experienced a radiation-induced complication. No patient developed a second malignancy during follow-up. Despite the limited number of patients enrolled, EBR may provide a mean of preserving eyeball and vision for some advanced lesions.

Familial retinoblastoma in developing countries

BACKGROUND

Although screening for familial retinoblastoma has been shown to be beneficial we suspected that such screening programs may be less than optimal in developing countries (DC).

METHODS

Retrospective cohort study comparing patients with familial retinoblastoma from five centers in DC (Argentina, Brazil, Turkey, Jordan, and Venezuela) versus a reference center in the USA.

RESULTS

Ninety-two (32 from the USA and 60 from DC) patients were included. Forty-one (44.6%) patients avoided enucleation, 42 (45.7%) had 1 eye removed, and 9 (9.8%) underwent bilateral enucleation. Eleven (11.9%) had major pathology risk factors at enucleation. There were no cases of metastatic disease at diagnosis. Detection via screening was significantly less common in DC than in the USA (23.3% vs. 71.8%, P < 0.0001). Patients in DC were diagnosed at a significantly later age and with more advanced intraocular disease that led to increased risk of bilateral enucleation. Patients detected by screening in DC were significantly younger at diagnosis, had less advanced intraocular disease, better ocular preservation rates and survival results than those whose retinoblastoma was not detected via early screening. Five-year pEFS was 0.92 for the patients treated in the USA and 0.81 for the patients in DC (P = 0.42). Seven events occurred (extraocular relapse four in patients from DC and second malignancies in three).

CONCLUSIONS

Patients with familial retinoblastoma are less likely to be diagnosed by screening in DC and had higher morbidity and mortality caused by recurrent extraocular retinoblastoma.

Retinoblastoma: a three-year-study at a Brazilian medical school hospital

OBJECTIVE

To present the characteristics and treatment outcomes of patients with retinoblastoma.

METHODS

A retrospective case series was conducted to review the records of all new patients diagnosed with retinoblastoma between 2003 and 2005. Eyes with early disease, or advanced disease with potential vision were treated with chemotherapy (carboplatin and etoposide) in conjunction with early local therapy (laser or cryo). Radiotherapy was used in cases where the disease did not respond to the above protocols or in recurrent cases. Eyes in the late stage of disease with no potential vision in the initial examination or eyes and where conservative treatment had failed were enucleated.

RESULTS

In total, we reviewed 28 new cases of retinoblastoma, 15 of which were unilateral and 13 of which were bilateral (46%). These data correspond to a mean of 9.3 new cases per year (0.77 case/ month). The mean age at diagnosis was 33.8 months for unilateral cases, and 19.15 months for bilateral cases (p=0.015). Leucocoria was the major presenting symptom (75%). All but one patient with unilateral disease had the affected eye enucleated due to advanced disease (mean follow-up: 39.91 months). Among the 13 bilateral cases, 13 eyes (50%) were enucleated, 11 eyes (42.4%) were saved with chemotherapy in conjunction with local therapy and 2 eyes (7.6%) were saved using external beam radiotherapy (mean follow-up: 41.91 months). In unilateral and bilateral disease, pathology data revealed choroid involvement in 50% and 30%, respectively, and optic nerve invasion in 92% and 50%, respectively.

CONCLUSION

In this population, retinoblastoma was diagnosed too late and most eyes were consequently enucleated. In cases with bilateral disease, half of the eyes were preserved.

Analysis of ototoxicity in young children receiving carboplatin in the context of conservative management of unilateral or bilateral retinoblastoma

BACKGROUND

Carboplatin plays an important role in the conservative management of retinoblastoma, but is associated with risk of ototoxicity in these young children whose sensory prognosis may be also compromised by their loss of vision. This retrospective study analyzed the impact of carboplatin on hearing in the context of conservative management of children with retinoblastoma.

METHODS

Data for 175 children treated at the Institut Curie between 1994 and 2002 were analyzed.

RESULTS

Median age at diagnosis was 8 months (0-60). Carboplatin was administered on 3 days (200 mg/m(2)/day) or 5 days (160 mg/m(2)/day) with etoposide and with diode-laser therapy at the dose of 560 mg/m(2) (chemothermotherapy). Median cumulative dose of carboplatin was 2,880 mg/m(2) (560-6,160). Ototoxicity was investigated by pure-tone audiometry and scored by Brock's grading scale before and after treatment. The median follow-up of hearing assessment was 5 years (1.8-11). Ototoxicity was detected in 8 children: 3 grade 1, 1 grade 2, and 2 grade 4. The two patients with grade 4 hearing-loss required a hearing aid. Two children developed bilateral high frequency hearing-loss, considered to be secondary to carboplatin but with less than Brock grade 1. Ototoxicity was observed for a median cumulative dose of carboplatin of 3,120 mg/m(2) (1,200-5,830). Only one child developed ototoxicity during treatment. All other cases were discovered after the last dose of carboplatin with a median interval of 3.7 years (0-7.6). No other risk factor for ototoxicity was able to account for these lesions.

CONCLUSION

Children receiving carboplatin require long-term audiometric follow-up.

Behavioural functioning of retinoblastoma survivors

OBJECTIVE

To assess behavioural problems in retinoblastoma (RB) survivors.

METHODS

This population-based cross-sectional study included 148 RB survivors (8-35 years), registered in the Dutch national RB register. Survivors and parents were asked to fill in behavioural questionnaires. Prevalence rates were computed, based on both self-reports and proxy reports. One-sample T-tests were applied to analyse differences compared with healthy reference samples. Multiple regression analyses were performed to identify predictors for behavioural problems within the RB sample.

RESULTS

Between-group differences varied across informants and across age groups. Parents reported significantly elevated total problem behaviour in 30% of their offspring (aged 8-17 years); this against 9% in adolescents (12-17 years) and 12% in adults (18-35 years) based on self-report. Parental reports showed significantly elevated rates of (1) internalising problems in boys and (2) somatic complaints in both girls and boys. Self-reports indicate significantly lowered levels of (1) externalising problems in adolescent and adult women and (2) thought problems in female adolescents and in adult men. Especially survivors who suffered hereditary RB, who had undergone more intensive treatment, and who came from a single-parent family were identified to be at most behavioural risk.

CONCLUSION

Perception of severity and the nature of behavioural problems seem to differ between beholder, and to vary between age groups, if not between life stages. Health professionals should be aware that especially those who are confronted with hereditary RB and who subsequently undergo intensive treatment, and who grow up in broken families, run the risk of developing behavioural difficulties.

Retinoblastoma: one world, one vision

Retinoblastoma is curable when diagnosed early and treated appropriately; however, the prognosis is dismal when the basic elements of diagnosis and treatment are lacking. In developing countries, poor education, lower socioeconomic conditions, and inefficient health care systems result in delayed diagnosis and suboptimal care. Furthermore, the complexity of multidisciplinary care required is seldom possible. Whereas ocular salvage is a priority in the Western world, death from retinoblastoma is still a major problem in developing countries. To bring the 2 ends of this spectrum together and provide a forum for discussion, the "One World, One Vision" symposium was organized, at which clinicians and researchers from various cultural, geographic, and socioeconomic backgrounds converged to discuss their experiences. Strategies for early diagnosis in developing countries were discussed. Elements of the development of retinoblastoma centers in developing countries were discussed, and examples of successful programs were highlighted. An important component in this process is twinning between centers in developing countries and mentor institutions in high-income countries. Global initiatives by nongovernmental organizations such as the International Network for Cancer Treatment and Research, Orbis International, and the International Agency for Prevention of Blindness were presented. Treatment of retinoblastoma in developing countries remains a challenge; however, it is possible to coordinate efforts at multiple levels, including public administrations and nonprofit organizations, to improve the diagnosis and treatment of retinoblastoma and to improve the outcome for these children.

A retrospective review of hearing in children with retinoblastoma treated with carboplatin-based chemotherapy

BACKGROUND

Retinoblastoma occurs in approximately 4 per million children per year in the United States, usually before 2 years of age. In developed countries, 95% of children with tumor in one eye can be cured with enucleation, while children with tumor in both eyes require individualized therapy to preserve vision. Although enucleation and radiation are very effective therapies for children with bilateral disease, the resultant visual impairment, cosmetic deformity and risk for new tumors result in morbidity to these children who otherwise have a near normal lifespan. Therefore, since 1994, chemoreduction with vincristine, carboplatin, and etoposide combined with focal treatment, have been used successfully. However, a major concern with the use of carboplatin has been ototoxicity.

PROCEDURES

To determine whether carboplatin, in the doses and schedule used by us and others to treat retinoblastoma (18.6 mg/kg q 4 weeks for six cycles) results in hearing impairment, we reviewed the records of 248 children with retinoblastoma, 164 of whom had received carboplatin. Children generally received carboplatin, vincristine, and etoposide (CEV) for six cycles of chemotherapy.

RESULTS

Hearing evaluations prior to initiating therapy were abnormal in 14 patients (5.6%). No patients with normal initial audiograms were found to have abnormal studies following repeated evaluations.

CONCLUSION

While ototoxicity is a potential concern in this young patient population, carboplatin in the treatment of retinoblastoma does not appear to produce impairment. Screening can identify children who require frequent audiologic follow-up, but children whose hearing is normal prior to therapy do not require routine surveillance following six cycles of standard CEV therapy.

Current management strategies for intraocular retinoblastoma

Survival rates for retinoblastoma patients have increased dramatically over the last century, with documented 5-year survival figures reaching 87-99% in developed countries. During the last decade, there has been a dramatic paradigm shift in the treatment approach for intraocular retinoblastoma, emphasising chemoreduction protocols and minimising the use of external beam radiation. The recognition of the increased risk for second non-ocular cancers with external beam radiation contributed to the growing emergence of chemotherapy. Although chemoreduction protocols vary slightly between institutions, many centres are currently treating intraocular retinoblastoma with carboplatin, vincristine and etoposide as a three-drug regimen given in two to six cycles. Clinical studies have demonstrated that systemic chemotherapy must be combined with other modalities, such as laser treatment and cryotherapy, for adequate tumour control and many eyes with advanced intraocular disease require salvage therapy with radiation or enucleation. Therefore, modern centres treating retinoblastoma continue to manage patients with a variety of modalities, individualising the therapy according to the patient's presentation and clinical course.

Health-related quality of life of child and adolescent retinoblastoma survivors in the Netherlands

Background

To assess health-related quality of life (HRQoL) in children (8–11 years) and adolescents (12–18 years) who survived retinoblastoma (RB), by means of the KIDSCREEN self-report questionnaire and the proxy-report version.

Methods

This population-based cross-sectional study (participation rate 70%) involved 65 RB survivors (8–18 years) and their parents. Child/adolescents' and parents' perception of their youth's HRQoL was assessed using the KIDSCREEN, and the results were compared with Dutch reference data. Relations with gender, age, marital status of the parents, and visual acuity were analyzed.

Results

RB survivors reported better HRQoL than did the Dutch reference group on the dimensions "moods and emotions" and "autonomy". Increased ratings of HRQoL in RB survivors were mainly seen in perceptions of the younger children and adolescent girls. RB survivors with normal visual acuity scored higher on "physical well-being" than visually impaired survivors. Age was negatively associated with the dimensions "psychological well-being", "self-perception" (according to the child and parent reports) and "parent relations and home life" (according to the child). "Self-perception" was also negatively associated with visual acuity (according to the child). Only parents of young boys surviving RB reported lower on "autonomy" than the reference group, and parents of low visual acuity and blind RB survivors reported higher on "autonomy" than parents of visually unimpaired survivors. Survivors' perceptions and parents' perceptions correlated poorly on all HRQoL dimensions.

Conclusion

RB survivors reported a very good HRQoL compared with the Dutch reference group. The perceptions related to HRQoL differ substantially between parents and their children, i.e. parents judge the HRQoL of their child to be relatively poorer. Although the results are reassuring, additional factors of HRQoL that may have more specific relevance, such as psychological factors or coping skills, should be explored.

Quality of life of adult retinoblastoma survivors in the Netherlands

Background

To assess the quality of life (QoL) and predictors thereof in Dutch adult hereditary and non-hereditary retinoblastoma (RB) survivors.

Methods

In this population-based cross-sectional study, a generic QoL questionnaire (SF-36) and a disease-specific interview were administered to 87 adult RB survivors aged 18 to 35 years. Their QoL data were compared with those of a Dutch healthy reference group. Among the RB hereditary/non-hereditary survivors, the QoL was compared and predictors for QoL were identified by linear multiple regression analyses.

Results

As a group, RB survivors scored significantly lower than the reference group on the SF-36 subscale 'mental health' (t = -27, df = 86, p < 0.01). Hereditary RB survivors scored lower on the subscale 'general health' (t = 2.6, df = 85, p < 0.01) than non-hereditary RB survivors. Having experienced bullying, as a child was a predictor for the SF-36 subscales: 'physical functioning' (p < 0.05), 'role functioning physical' (p < 0.01), 'role functioning emotional' (p < 0.05) and 'social functioning' (p < 0.01). Having experienced bullying (p < 0.01), but also subjective experience of impairment related to RB (p < 0.05), was predictors for 'general health'. Subjective experience of impairment was a predictor for 'vitality' (p < 0.01) and 'bodily pain' (p < 0.01).

Conclusion

In this exploratory study, it appears that the group of adult RB survivors experience a relatively good overall but slightly decreased QoL compared with the reference group. However, they report more problems with regard to their mental health (anxiety, feelings of depression, and loss of control). Hereditary RB survivors differ significantly from non-hereditary RB survivors only in 'general health'. Bullying in childhood and subjective experience of impairment are the main predictors of a worse QoL. In order to prevent worsening of QoL, or perhaps to improve it, clinicians should make an inventory of these issues at an early stage. We recommend further research to assess the specific psychological factors that may lead to mental health problems in this population.