Intravitreal injection of melphalan for intraocular retinoblastoma

A pilot study of intraoperative melphalan to prevent recurrent PVR: the IOMPVR study

BACKGROUND

Proliferative vitreoretinopathy (PVR) is a major cause of failure in cases of retinal detachment (RD) repair. Intravitreal melphalan, a known inhibitor of cellular proliferation, offers a novel therapeutic approach to reduce PVR recurrence and improve outcomes. We evaluated the safety and efficacy of 5 µg/0.1 ml intravitreal melphalan at the end of pars plana vitrectomy (PPV) before silicone oil (SO) injection in eyes with primary PVR related to rhegmatogenous retinal detachments (RRDs) with a minimal 90-day follow-up period.

METHODS

This prospective, cross-sectional, interventional pilot study was conducted at the Department of Ophthalmology of the Federal University of São Paulo in patients with primary RRD and PVR. Patients were included who were aged 18 to 85 years with PVR grade CP2 or worse secondary to RRDs in eyes without having undergone a previous RRD surgery. They underwent PPV + scleral buckle + fluid air exchange followed by intravitreal injection of 5 µg/0.1 ml melphalan (270 mOsm) and SO injection.

RESULTS

Six eyes of six patients were enrolled. Ocular examination and imaging showed no retinal toxicity. The logarithm of the minimum angle of resolution best-corrected visual acuity improved from the mean ± standard deviation preoperatively of 2.11 ± 0.22 to 0.89 ± 0.37 at 30 and to 0.84 ± 0.42 at 90 days postoperative (P < 0.001). Optical coherence tomography identified intraretinal cysts in five of six eyes and outer retinal layer loss in all study eyes. Only one of six eyes developed a recurrent localized RD on day 90 unrelated to recurrent PVR. PVR recurrence was not observed during the study follow-up.

CONCLUSIONS

In this pilot study, the preliminary data showed that PPV followed by intravitreal injection of 5 µg/0.1 ml melphalan was not related to ocular toxicity. The absence of PVR recurrence at 3 months follow-up in these complex PVR eyes is an interesting finding that justifies further investigation.

The Role of Intravitreal Chemotherapy as an Adjunctive Treatment for Retinoblastoma: A Systematic Review and Single-Arm Meta-Analysis

TOPIC

evaluation of clinical outcomes of patients with retinoblastoma treated with intravitreal chemotherapy (IvitC).

DESIGN

Systematic review and single-arm meta-analysis CLINICAL RELEVANCE: Clinical outcomes with IVitC vary across reports according to patient characteristics and concomitant treatment modalities, mainly intravenous chemotherapy (IVC) and intra-arterial chemotherapy (IAC). There are currently no large clinical trials or meta-analyses focusing on the topic.

METHODS

A systematic search was conducted in MEDLINE, EMBASE and Cochrane. All articles reporting use of IVitC for RB and safety or efficacy outcomes were included regardless of publication date. Studies with fewer than 10 eyes were excluded. Enucleation rates (ER) were calculated using proportions and 95% confidence intervals (CIs). The analysis was performed using the Random Effects model in R Studio.

RESULTS

25 studies comprising 1082 eyes met inclusion criteria. Melphalan was exclusively used in 687 eyes (63.49%), 104 eyes received topotecan exclusively (9.61%), and the remaining 291 (26.90%) used a combination. General ER was 24.70% (95% CI 19.20-31.18%). Subgroup analysis showed an ER of 27.76% (95% CI 19.05-38.55%) for melphalan, 14.23% (95% CI 5.61-21.66%) for topotecan, and 23.82% (95% CI 11.95-41.87%) for combination therapy (P < .05). It also revealed an ER of 21.54% (95% CI 15.57-29.01%) for studies that implemented IAC+IVitC versus 35.50% (95% CI 20.73-53.66%) for those who used IVC+IVitC (P < .05). Pigmentary retinopathy rate was 36.56% (95% CI 24.61-50.44%) in subjects treated with melphalan and 2.42% (95% CI 0.70-8.01%) for those receiving topotecan (P < .05). Other adverse events were cataract (17.76%) followed by vitreous hemorrhage (12.10%) and retinal detachment (5.62%). All studies, except 1, were determined to have a serious risk of bias.

CONCLUSION

IVitC represents an effective strategy for retinoblastoma, especially when administered after IAC; however, melphalan retinal toxicity still poses a challenge. Results with topotecan are promising but scarce. Comparing both drugs is needed to define the best treatment strategy. This study is limited by the lack of large, randomized studies on this subject.

Intraocular Surgery for Retinoblastoma: An Evaluation of Current Evidence

Background

Retinoblastoma (Rb) is the most common intraocular malignancy of childhood. The prognosis in Rb directly relates to the spread of disease beyond the eye, particularly to the central nervous system. Therefore, until the recent past, surgically entering an eye with active or recently active Rb was absolutely contraindicated in most centres around the world due to the risk of iatrogenic extraocular spread.

Summary

In this review article, we explore the role of intraocular surgery in Rb. We describe the techniques which have been developed in order to safely deliver chemotherapeutic agents into the eye, both intravitreal and intracameral. We discuss the role of vitrectomy and endoresection for treatment of vitreous seeds and active retinal tumours. In the context of previously treated Rb, we outline various surgical interventions performed to improve visual outcomes or to manage the ocular sequelae of the disease. In particular, we review the various techniques used to maximise the safety of cataract, retinal and glaucoma surgery in children with a history of Rb.

Key Messages

The role of intraocular surgery in Rb is now well established, particularly in the delivery of chemotherapeutic agents or in the presence of previously treated diseases. The role of intraocular surgery in eyes with active Rb is less well established and remains the subject of much debate. However, it is likely that with further development of safer surgical techniques, the indications and modalities will continue to broaden.

Varied toxicity profile of intravitreal melphalan in two retinoblastoma eyes

Retinoblastoma (RB) is the most common primary intraocular malignant tumor of childhood. Persistent or recurrent vitreous seeding is the most common reason for therapeutic failure in advanced RB. Intravitreal chemotherapy has emerged as an effective therapy for vitreous seeding in RB, with a generally acceptable safety profile. However, intravitreal chemotherapeutics, especially melphalan, can cause toxicity that may progress to total retinal atrophy. In this report, we present two cases with retinal melphalan toxicity that had varied clinical findings. One of the cases had extensive retinal atrophy that was demonstrated by hand-held spectral domain optical coherence tomography (HHSD-OCT), while the other had normal retinal anatomy on HHSD-OCT but markedly diminished retinal function on flash electroretinography.

Safety of intravitreal chemotherapy in the management of retinoblastoma: A systematic review of the literature

Intravitreal chemotherapy is used as a salvage therapy for retinoblastoma with persistent or recurrent vitreous seeding after primary treatment. To assess the safety of this technique, we conducted a systematic review of all studies reporting ocular toxicity data. Forty-eight trials involving 2751 eyes were included. The most common complications were cataract, retinal toxicity, and vitreous hemorrhage. However, severe and permanent adverse events were limited, while the risk of extraocular dissemination, a significant concern, was practically eliminated through preventive techniques. Globe salvage rates ranged from 29 % to 100 %. In conclusion, intravitreal chemotherapy seems to improve prognosis of eyes with advanced disease, with an acceptable safety profile. Nevertheless, most relevant studies are retrospective, and no randomized trials have been performed. Recognizing the challenges regarding the conduct of randomized studies for such a rare pediatric cancer, we believe that multicenter trials through international collaborations can significantly enhance the available information.

Selective ophthalmic arterial injection using a balloon catheter for retinoblastoma: a seven-year clinical evaluation

PURPOSE

To evaluate the effectiveness and safety of selective ophthalmic arterial injection (SOAI) for retinoblastoma utilizing a microballoon catheter system with an M chamber.

STUDY DESIGN

Retrospective analysis.

METHODS AND PATIENTS

This study was sanctioned by theNational Cancer Center Hospital' Independent Ethics Committee. The surgeon was a general interventional radiologist. After confirming that the distal internal carotid artery was not delineated by balloon occlusion and the ophthalmic artery was visualized using digital subtraction angiography, melphalan was manually administered. Notably, in cases presenting bilateral retinoblastoma, both eyes received treatment in a singular, low-dose procedure. Between July 2015 and December 2021, 125 patients with retinoblastoma (68 boys and 57 girls) underwent SOAI at our facility. The average age at initial treatment was 19.3 months. The study covered 250 procedures, with patients undergoing an average of 3.7 procedures.

RESULTS

The success rate of the procedure was 99.2%, with a mean procedure duration of 18.3 min. Two distinct technical failures were recorded: one attributed to an internal carotid artery having a wide lumen and the other due to the ophthalmic artery remaining undetected on angiography post-balloon occlusion of the internal carotid artery. Adverse events were minimal but included bronchospasm post-procedure and severe orbital inflammation in 0.8% and 0.4% of cases, respectively.

CONCLUSION

SOAI using the microballoon catheter with the M chamber is a feasible and safe procedure for the treatment of retinoblastoma. The success rate was 99.2%. This system can be recommended as intra-arterial chemotherapy for retinoblastoma.

Liposomal Phenylephrine Nanoparticles Enhance the Antitumor Activity of Intratumoral Chemotherapy in a Preclinical Model of Melanoma

Intratumoral injection of anticancer agents has limited efficacy and is not routinely used for most cancers. In this study, we aimed to improve the efficacy of intratumoral chemotherapy using a novel approach comprising peri-tumoral injection of sustained-release liposomal nanoparticles containing phenylephrine, which is a potent vasoconstrictor. Using a preclinical model of melanoma, we have previously shown that systemically administered (intravenous) phenylephrine could transiently shunt blood flow to the tumor at the time of drug delivery, which in turn improved antitumor responses. This approach was called dynamic control of tumor-associated vessels. Herein, we used liposomal phenylephrine nanoparticles as a "local" dynamic control strategy for the B16 melanoma. Local dynamic control was shown to increase the retention and exposure time of tumors to intratumorally injected chemotherapy (melphalan). C57BL/6 mice bearing B16 tumors were treated with intratumoral melphalan and peri-tumoral injection of sustained-release liposomal phenylephrine nanoparticles (i.e., the local dynamic control protocol). These mice had statistically significantly improved antitumor responses compared to melphalan alone (p = 0.0011), whereby 58.3% obtained long-term complete clinical response. Our novel approach of local dynamic control demonstrated significantly enhanced antitumor efficacy and is the subject of future clinical trials being designed by our group.

Intravitreal Topotecan for Vitreous Seeds in Retinoblastoma: A Long-term Review of 91 Eyes

PURPOSE

To study the long-term efficacy of intravitreal topotecan (IVT) for vitreous seeds in eyes with retinoblastoma and risk factors for their recurrence.

DESIGN

Retrospective, non-comparative, interventional study.

PARTICIPANTS

Ninety-one eyes of 90 patients with retinoblastoma treated between January 2013 and April 2019.

METHODS

Patients with recurrent or refractory vitreous seeds after completion of intravenous or intra-arterial chemotherapy were treated with IVT (30 μg/0.15 ml) by the safety-enhanced technique. The injection was repeated every 4 weeks until the regression of seeds. Patients with a minimum follow-up of 12 months were included in the analysis.

MAIN OUTCOME MEASURES

Primary outcome measures were vitreous seed regression and eye salvage. Secondary outcomes were risk factors for vitreous seed recurrence after treatment with IVT, vision salvage, and complications of IVT.

RESULTS

The median age of the patients was 18 months, with most having group D (n = 58 [64%]) and group E (n = 26 [29%]) retinoblastoma. Vitreous seeds were refractory in 46 eyes (51%) and recurrent in 45 eyes (49%). A total of 317 IVT injections were administered, with the median being 3 injections. The median number of IVT injections required was 2.5 injections for dust, 3 injections for sphere, and 5 injections for cloud morphologic features. Recurrence of vitreous seeds after IVT was seen in 17 eyes (19%) at a mean follow-up of 7.9 months. At a mean follow-up 34 months, vitreous seed regression was achieved in 88 eyes (97%) and eye salvage was achieved in 77 eyes (85%). Older age (P = 0.018) and recurrence of retinal tumor (15/17 eyes; P < 0.01) significantly increased the risk of vitreous seed recurrence. Cataract was the most common complication seen in 17 eyes (9%).

CONCLUSIONS

Intravitreal topotecan at an every 3- to 4-week regimen is effective against both refractory and recurrent vitreous seeds. The vitreous seed morphologic features correspond to the number of injections required for regression. Increasing age and recurrence of retinal tumor increase the risk of vitreous seed recurrence after treatment with IVT.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Evidence in Focus: The Sparse Landscape of Randomized Trials on Retinoblastoma Treatment

Background

Retinoblastoma, although rare, is one of the most common intraocular malignancies worldwide. Its prognosis has improved significantly in the past few decades, thanks to modern treatments, like systemic, intra-arterial, and intravitreal chemotherapy. However, regarding survival, there are significant differences between high- and low-income countries, eye salvage is still a challenge worldwide, and treatment-related toxicity needs to be carefully and sufficiently managed.

Summary

To appraise the strength of supporting evidence, we performed a systematic review of randomized controlled trials investigating any therapeutic protocol for retinoblastoma. Four trials with 174 participants (188 eyes) were eligible, all pertaining to different intravenous chemotherapy regimens. Vincristine, etoposide, and carboplatin (VEC) appear superior to a 5-drug combination for stage III retinoblastoma. Moreover, etoposide and carboplatin as neoadjuvant chemotherapy followed by thermochemotherapy seem to offer better local control than vincristine and carboplatin. However, increasing carboplatin dose in the VEC protocol failed to improve treatment efficacy.

Key Messages

Retinoblastoma is a success story of modern medicine. However, only intravenous chemotherapy has been studied through randomized trials, while evidence for the most novel retinoblastoma treatments has mainly stemmed from observational studies. International collaborations for multicenter randomized trials could overcome difficulties and increase certainty and precision in the field.

Advancements in Retinoblastoma Treatment: Unraveling the Potential of Intravitreal Chemotherapy

Retinoblastoma necessitates urgent attention due to its potential fatality if untreated. Multiple treatment options are available and should be employed according to size, location, and the extent of dissemination. This review emphasizes the need for increased awareness, advanced diagnostic tools, and innovative treatment approaches, especially intravitreal chemotherapy (IVitC) to address the diverse manifestations and aggressive nature of retinoblastoma. Timely diagnosis and commitment to treatment are pivotal, as delays and reluctance to undergo enucleation contribute to unfavorable outcomes. The evolving treatment landscape, spanning from traditional interventions to modern targeted therapies such as intravitreal melphalan, holds promise for improved outcomes. While the intravitreal approach presents challenges, ongoing research aims to establish its definitive role in retinoblastoma treatment. In the treatment of retinoblastoma, IVitC raises considerations about side effects. The risk of tumor spread beyond the eye is rare, emphasising the potential of IVitC in carefully selected cases. Intravitreal injections exhibit fewer local adverse effects compared to intra-arterial chemotherapy, with careful measures reducing significant ocular complications. The evaluation of ocular toxicity, particularly with melphalan, underscores the importance of a nuanced approach to achieve the right balance between therapeutic efficacy and ocular safety. This comprehensive analysis of studies on IVitC and its ocular and systemic complications provides valuable insights for enhanced patient care. The review concludes with a focus on balancing safety and efficacy in local chemotherapeutic drugs, highlighting the need for thoughtful measures and continued research to optimise treatment modalities globally.

Presence of cataract in patients treated for retinoblastoma at the national institute of pediatrics in Mexico (2011-2021)

PURPOSE

The goal of this study is to describe the presence of secondary cataract in patients with retinoblastoma treated at the National Institute of Pediatrics of Mexico (INP) over the past 10 years.

METHODS

This was a single center observational, retrospective and descriptive study. We included all eyes diagnosed with retinoblastoma and cataract between June 2011 and June 2021.

RESULTS

In total, 833 records of patients diagnosed with Retinoblastoma at the National Institute of Pediatrics during the period between June 2011 and June 2021 were reviewed. Out of all of them, only 14 developed cataract (1.6%). The median age at retinoblastoma diagnosis was 10.5 months (Rank: 6-13 months), and the median age at cataract diagnosis was 51.5 months (Rank: 25-73 months). The majority (13, 92.9%) of the patients had bilateral involvement. 42% of the eyes were Stage D according to the international classification of retinoblastoma. Cryotherapy was applied in 57.1%, intravitreal chemotherapy in 85.7%, radiation therapy in 42.6%, and only 7.1% of cases were treated with intra-arterial chemotherapy.

CONCLUSIONS

The presence of cataract in patients with retinoblastoma is a rare but important entity impacting the development of vision in children and detection of intraocular tumors. These probably occur late as a result of the multiple treatments to which the children have been subjected, without being able to determine in this study which is the risk factor most associated with the development of this pathology.

Intravitreal Topotecan 90 µg for Recurrent Solid Retinoblastoma Tumors Is Effective and Not Toxic

The authors report on the safety and efficacy of 90 µg/0.18 cc of intravitreal topotecan for recurrent solid retinal tumors in retinoblastoma. Topotecan 90 µg was injected intravitreally in three retinoblastoma cases that progressed after prior therapy. Safety was monitored with retinal examinations under anesthesia and 30-Hz flicker electroretinograms. There was complete disappearance of recurrent retinal tumors with only one injection of 90 µg of intravitreal topotecan without any toxicity. Intravitreal 90 µg caused prompt regression of retinal tumors in three children who had progression of their retinoblastoma after prior therapy. No toxicity was seen. This is the first report of intravitreal 90 µg in humans and the first report of responses of retinal tumors from intravitreal topotrecan. [J Pediatr Ophthalmol Strabismus. 2023;60(2):e16-e18.].

Spotlight on Targeted Chemotherapy in Retinoblastoma: Safety, Efficacy, and Patient Outcomes

As the most common primary intraocular malignancy of childhood, retinoblastoma (RB) has had a complex journey in its management, following a course from enucleation as the first life-saving treatment to numerous globe-salvaging therapies during the last century. Currently, this potentially lethal disease has achieved high survival rates owing to multidisciplinary management and the introduction of neoadjuvant and multimodal chemotherapy. Therefore, the goal of treatment is shifting toward conserving the globe and vision as much as possible. Up until recently, many advanced cases of RB were enucleated primarily; however, targeted chemotherapy via the ophthalmic artery and management of intraocular seeding by local administration of chemotherapeutic agents have revolutionized the globe-conserving therapies. The added benefit of avoiding systemic complications of cytotoxic drugs resulted in these methods gaining popularity, and they are becoming a main part of care in many referral centers. Initially, there were some safety concerns regarding these approaches; however, increasing experience has shown that these modalities are relatively safe procedures and many complications can be averted by changing the choice of the drug and using some prophylactic measures. It is hoped that, in the near future, with advances in early diagnosis and patient-targeted molecular therapies, as well as gene-editing techniques, the patient's vision can be saved even in advanced RB.

A case of retinoblastoma resulting in phthisis bulbi after proton beam radiation therapy

Purpose

Proton beam radiation therapy (PBRT) is a treatment option for advanced retinoblastoma (RB) resistant to chemotherapy and focal ophthalmic treatment. Here we report a case of RB with phthisis bulbi following PBRT.

Observations

A 16-day-old boy with a family history of RB was referred to our institution. Initial examination revealed an extensive white mass in the right eye and a small tumor near the optic disk of the left eye. The patient was diagnosed with bilateral RB and treated with chemotherapy and focal ophthalmic therapy. The right eye showed shrinkage in the treatment course. The tumor control was not achieved bilaterally, and, therefore, PBRT was performed to preserve the eyes. However, the right eye became significantly phthisical following PBRT and ultimately required enucleation.

Conclusions and importance

PBRT for RB may result in phthisis bulbi. Further investigations of its role and possible complications are warranted.

Advances in biomaterials for the treatment of retinoblastoma

Retinoblastoma is the most common primary intraocular malignancy in children. Although traditional chemotherapy has shown some success in retinoblastoma management, there are several shortcomings to this approach, including inadequate pharmacokinetic parameters, multidrug resistance, low therapeutic efficiency, nonspecific targeting, and the need for adjuvant therapy, among others. The revolutionary developments in biomaterials for drug delivery have enabled breakthroughs in cancer management. Today, biomaterials are playing a crucial role in developing more efficacious retinoblastoma treatments. The key goal in the evolution of drug delivery biomaterials for retinoblastoma therapy is to resolve delivery-associated obstacles and lower nonlocal exposure while ameliorating certain adverse effects. In this review, we will first delve into the historical perspective of retinoblastoma with a focus on the classical treatments currently used in clinics to enhance patients' quality of life and survival rate. As we move along, we will discuss biomaterials for drug delivery applications. Various aspects of biomaterials for drug delivery will be dissected, including their features and recent advances. In accordance with the current advances in biomaterials, we will deliver a synopsis on the novel chemotherapeutic drug delivery strategies and evaluate these approaches to gain new insights into retinoblastoma treatment.

Ocular and systemic toxicity of high-dose intravitreal topotecan in rabbits: Implications for retinoblastoma treatment

Although many more eyes of children with retinoblastoma are salvaged now compared to just 10 years ago, the control of vitreous seeding remains a challenge. The introduction of intravitreal injection of melphalan has enabled more eyes to be salvaged safely but with definite retinal toxicity. Intensive treatment with high-dose intravitreal topotecan may be a strategy to control tumor burden because of its cell cycle-dependent cytotoxicity and the proven safety in humans. Therefore, we evaluated the ocular and systemic safety of repeated high-dose intravitreal injections of topotecan in rabbits. Systemic and ocular toxicity was assessed in non-tumor-bearing rabbits after four weekly injections of three doses of topotecan (10μg, 25μg, and 50μg) or vehicle alone. Animals were evaluated weekly for general and ophthalmic clinical status. One week after the last injection, vitreous and plasma samples were collected for drug quantification and the enucleated eyes were subjected to histological assessment. Weight, hair loss, or changes in hematologic values were absent during the study period across all animal groups. Eyes injected with all topotecan doses or vehicle showed no signs of anterior segment inflammation, clinical or histologic evidence of damage to the retina, and ERG parameters remained unaltered throughout the study. Vitreous and plasma topotecan lactone concentrations were undetectable. Four weekly intravitreal injections of topotecan up to 50μg in the animal model or a 100μg human equivalent dose were not toxic for the rabbit eye. High doses of topotecan may show promising translation to the clinic for the management of difficult-to-treat retinoblastoma vitreous seeds.

Pars plana vitrectomy for vitreoretinal complications in only seeing eyes after treatment for retinoblastoma

Purpose

To report the outcomes of two only seeing eyes of two cases with retinoblastoma in which vitrectomy was performed to treat vitreous hemorrhage or rhegmatogenous retinal detachment after treatment for retinoblastoma.

Observations

Case 1 was an 8-month-old girl whose bilateral retinoblastoma (group D, OU) was treated by chemotherapy and focal ablation therapy. As the tumor size increased, enucleation was required in the right eye. At 4 years of age, about 1 year after the last treatment for retinoblastoma, lens-sparing vitrectomy was performed for dense, nonclearing vitreous hemorrhage, which had occurred 6 months previously. No recurrence of the tumor was found, and the patient's visual acuity improved to 0.9 postoperatively. Case 2 was a 4-month-old boy who was diagnosed with bilateral retinoblastoma (group D, OD; group C, OS) and underwent treatment, including systemic and local chemotherapy and proton beam therapy. Because large, regressed tumor masses were present in the posterior pole of the right eye, the left eye was the only seeing eye. At the age of 1 year 7 months, retinal detachment developed in the left eye 1 month after cryotherapy was performed for tumor recurrence. Although a scleral buckling procedure without drainage was performed, the retina was not reattached. The retina was reattached after vitrectomy with melphalan irrigation and silicone oil tamponade. However, recurrence was noted 6 months after the operation, and enucleation was required.

Conclusion and importance

Vitrectomy appears to be beneficial for the treatment of vision-threatening complications after retinoblastoma treatment. However, vitrectomy may be associated with the potential spread of tumor cells and/or tumor recurrence and therefore should be reserved as the last treatment modality for only seeing eyes. Careful postoperative follow-up is mandatory.

•

Pars plana vitrectomy was performed in two only seeing eyes of two cases.

•

In a case with nonclearing vitreous hemorrhage and tumor regression over 1 year, visual acuity improved to 0.9 postoperatively without recurrence.

•

In the other case with retinal detachment and vitreous seeding required enucleation for tumor recurrence.

Recurrence and new tumor development after frontline intravenous chemotherapy for retinoblastoma: Risk factors and treatment results

PURPOSE

To evaluate the risk factors leading to recurrence and new tumor (NT) development in patients with retinoblastoma after intravenous chemotherapy (IVC) and to review the treatment outcomes.

MATERIALS AND METHODS

The records of 166 retinoblastoma cases (having 246 affected eyes) who underwent six-cycle IVC (vincristine, etoposide, and carboplatin) as primary treatment between October 1999 and August 2020 were reviewed retrospectively.

RESULTS

The mean ages at presentation were 9.0 (median: 8.0) and 9.2 (median: 8.5) months in cases with recurrence and NTs respectively. Recurrence was detected in 40 (16.3%) eyes, NTs in 29 (11.8%), and both recurrence/NTs in 24 (9.8%). The mean time elapsed till recurrence and NT was 10.7 months. Multivariable analysis showed that the factors predictive of recurrence were largest tumor base diameter (LTBD) >12 mm (p = 0.039) and presence of subretinal seeds at diagnosis (p = 0.043). Multivariable risk factors for the development of NTs were bilateral familial retinoblastoma (p = 0.001) and presence of subretinal seeds at diagnosis (p = 0.010). Mean follow-up was 80.1 (median: 72.5) months. By Kaplan-Meier analysis, the 1-, 3-, and 6-year recurrence and NT rates were 21.2%, 28.1%, and 28.7% and 14.9%, 22.6%, and 23.9% respectively. The most common treatment methods used for recurrent and/or NTs included cryotherapy, transpupillary thermotherapy, and intra-arterial chemotherapy. Enucleation was eventually required in 24/93 (25.8%) eyes. No patient developed metastasis.

DISCUSSION

Development of recurrence and/or NT after IVC was noted in 38% of all retinoblastoma eyes. Bilateral familial disease, LTBD >12 mm, and presence of subretinal seeds at baseline were risk factors for recurrence and NTs in this study.

Hsa_circ_0099198 facilitates the progression of retinoblastoma by regulating miR-1287/LRP6 axis

Retinoblastoma (RB) is an intraocular malignancy that occurs in children. Circular RNAs (circRNAs) have been confirmed to play an essential role in tumorigenesis and development. This study aimed to ascertain the role and potential mechanism of hsa_circ_0099198 in RB. The levels of circ_0099198, microRNA-1287 (miR-1287) and low-density lipoprotein receptor-related protein 6 (LRP6) were determined by real-time quantitative polymerase chain reaction and Western blot. Cell proliferation was assessed by colony formation assay. Cell cycle arrest and apoptosis were evaluated by flow cytometry. Cell migration and invasion were tested using transwell assay. The activity of caspase-3/caspase-9 was examined with commercial kits. The interaction among circ_0099198, miR-1287 and LRP6 were verified by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay or RNA pull-down assay. Xenograft experiment was used to assess tumor growth in vivo. circ_0099198 and LRP6 levels were increased, while miR-1287 level was reduced in RB cells. circ_0099198 silencing suppressed proliferation and metastasis and expedited cell cycle arrest and apoptosis in Y79 and So-RB50 cells. In addition, depletion of circ_0099198 inhibited RB cell progression via regulating miR-1287/LRP6 axis. Moreover, knockdown of circ_0099198 blocked the growth of xenograft tumors. circ_0099198 contributed to RB progression by sponging miR-1287 and up-regulating LRP6, which provided novel biomarkers for RB therapy.

Outcomes of Group D Retinoblastoma With Resistant Vitreous Seeds After Integration of Intravitreal Chemotherapy to the Treatment Protocol

Introduction: A major therapeutic challenge in the salvage of Group D retinoblastoma eyes is the poor response of vitreous seeds to intravenous chemotherapy. The novel use of intravitreal melphalan has greatly impacted the salvage of such eyes; however, concerns regarding its safety and toxicity still exist, particularly in dark-eyed children. This study aims to evaluate our experience and determine the visual and anatomical outcomes of intravitreal melphalan in group D retinoblastoma with resistant vitreous seeds.

Method: All patients, from August 2018 to February 2020, with group D retinoblastoma harboring vitreous seeds refractory to first-line chemo reduction regimen with vincristine, etoposide, and carboplatin for six cycles plus local consolidation with thermotherapy or cryotherapy were evaluated. Fifteen eyes of 15 patients that fulfilled the eligibility criteria and received intravitreal melphalan were retrospectively reviewed for demographics, iris color, treatments offered, seed inactivation, globe survival, visual acuity, and complications.

Result: Mean age at presentation was 22 months for bilateral disease and 36 months for unilateral disease. A total of 77 injections were administered (mean, five injections per eye) with doses ranging from 20 µg to 30 µg. Complete seed control was seen in 13 of 15 (87%) eyes, and globe salvage was possible in 11 of 15 (73%) eyes. Eyes with macular tumor had visual acuity ranging from 6/36 (0.8) to 6/60 (1.0). SIx of eight eyes (75%) with extra macular tumors had vision 0.4 or better.

Conclusion: Intravitreal melphalan seems like a promising treatment modality in group D retinoblastoma with resistant vitreous seeds having dark eyes. Amblyopia therapy may play an important role in attaining maximal visual benefits in these children.

Ocular surface complications of local anticancer drugs for treatment of ocular tumors

Local chemotherapy is increasingly used, either in combination with surgery or as monotherapy, for management of ocular tumors. Yet many of the local chemotherapeutic agents used for ocular tumors are cytotoxic drugs that are frequently associated with toxicities in normal ocular tissues. Understanding and managing these side effects are important because they affect treatment tolerability, outcome and quality of vision. Herein, we review local anticancer drugs administered for the treatment of ocular tumors, with an emphasis on their toxicities to the ocular surface, adnexa and lacrimal drainage system. We provide the underlying mechanisms and management strategies for the ocular side effects. Recent innovations in anticancer immunotherapy and ocular drug delivery systems also are discussed as new potential therapeutic modalities for alleviation of side effects.

An Overview of Retinoblastoma and Enucleation in Pediatric Patients

Retinoblastoma is a rare malignancy of the eye affecting children, most commonly four years old and younger. Although chemotherapy and radiation treatment aim to spare the eye, in some cases, enucleation (ie, removal of the eye) is required to prevent cancer metastases or recurrence. Enucleation procedures are primarily performed at specialty institutions and may involve the surgical placement of an implant in the orbit of the eye. Unique perioperative considerations are required because of the age of the child at the time of the diagnosis and procedure and the involvement of a parent or caregiver who will be caring for the child postoperatively. This article presents an overview of retinoblastoma and enucleation and discusses the care and management of the unique patient population undergoing enucleation.

Secondary intra-arterial chemotherapy and/or intravitreal chemotherapy as salvage treatment for retinoblastoma

PURPOSE

To evaluate the results of secondary intra-arterial chemotherapy (IAC) and/or intravitreal chemotherapy (IVC) as a salvage treatment for retinoblastoma (RB).

MATERIALS AND METHODS

The medical records of 31 (20 male, 11 female) cases (with 38 eyes) who underwent secondary IAC and/or IVC between February 2010 and June 2019 were retrospectively reviewed.

RESULTS

Thirteen (41.9%) cases had unilateral and 18 (58.1%) had bilateral RB. According to the International Classification of RB, 6 (15.8%) eyes had group B, 9 (23.7%) eyes had group C, 16 (42.1%) eyes had group D, and 7 (18.4%) eyes had group E RB at diagnosis. All patients underwent six-cycle intravenous chemotherapy as primary treatment and 8 eyes received external radiotherapy before IAC/IVC. Secondary IAC was performed in 21 (55.3%) eyes, IVC in 10 (26.3%) eyes, and IAC + IVC in 7 (18.4%) eyes. External radiotherapy was applied in 2 (5.3%) eyes after IAC/IVC, one of which was later enucleated. In total, 17 (44.7%) eyes undergoing secondary IAC/IVC treatments were enucleated. Metastasis and death were not observed in any case during the mean follow-up period of 59.3 (median 61, range: 10-98) months.

DISCUSSION

Although 60.5% of the eyes undergoing IAC/IVC consisted of groups D and E RB, globe salvage and survival rates were 55.3% and 100.0%, respectively. External radiotherapy was required in 5.3% of the eyes after IAC/IVC. In conclusion, IAC and IVC are safe and effective treatment methods in eyes with RB unresponsive to other eye-preserving treatments and those demonstrating recurrence.

Retinoblastoma: Etiology, Modeling, and Treatment

Retinoblastoma is a retinal cancer that is initiated in response to biallelic loss of RB1 in almost all cases, together with other genetic/epigenetic changes culminating in the development of cancer. RB1 deficiency makes the retinoblastoma cell-of-origin extremely susceptible to cancerous transformation, and the tumor cell-of-origin appears to depend on the developmental stage and species. These are important to establish reliable preclinical models to study the disease and develop therapies. Although retinoblastoma is the most curable pediatric cancer with a high survival rate, advanced tumors limit globe salvage and are often associated with high-risk histopathological features predictive of dissemination. The advent of chemotherapy has improved treatment outcomes, which is effective for globe preservation with new routes of targeted drug delivery. However, molecularly targeted therapeutics with more effectiveness and less toxicity are needed. Here, we review the current knowledge concerning retinoblastoma genesis with particular attention to the genomic and transcriptomic landscapes with correlations to clinicopathological characteristics, as well as the retinoblastoma cell-of-origin and current disease models. We further discuss current treatments, clinicopathological correlations, which assist in guiding treatment and may facilitate globe preservation, and finally we discuss targeted therapeutics for future treatments.

[Tumors and Pseudotumors of the Retina and the Ciliary Epithelium]

The variety of retinal tumors ranges from harmless lesions to benign, locally destructive tumors and life-threatening diseases, and they are not always easy to distinguish from each other. The differential diagnosis includes real neoplasia, reactive inflammatory pathologies and vascular anomalies of the fundus as well. If possible, the diagnosis should be made clinically in order to avoid the danger of tumor cell spread via invasive diagnostic tools. Nevertheless, genetic analysis of the pathology is gaining more importance and adds to the precise characterization of the diagnosis. Depending on the tumor entity, therapy in a specialized center is necessary.

Tumoren und Pseudotumoren der Netzhaut und des Ziliarepithels

Die Varietät retinaler Tumoren reicht von harmlosen Läsionen über benigne, lokal destruierende Tumoren bis hin zu lebensbedrohlichen Erkrankungen. Nicht immer lassen sie sich einfach voneinander unterscheiden. Die Diagnose sollte nach Möglichkeit klinisch gestellt werden wegen der Gefahr einer Tumorzellverschleppung durch invasive Diagnostik. Jedoch rückt die genetische Charakterisierung der Läsion immer mehr in den Vordergrund. Je nach Entität ist eine Therapie in einem spezialisierten Zentrum notwendig.

Comparison of intravitreal melphalan with and without topotecan in the management of vitreous disease in retinoblastoma

PURPOSE

To evaluate clinical outcomes and enucleation rates after intravitreal melphalan (IVM) alone and after IVM combined with intravitreal topotecan (IVT) for the treatment of vitreous disease, and to a lesser extent subretinal and retrohyaloid seeds, in patients with retinoblastoma.

STUDY DESIGN

A retrospective analysis of 77 eyes of 72 consecutive patients.

METHODS

Demographic data, classification of tumors, seed type (dust, sphere or cloud) before injection and at the end of follow-up, injection type (IVM or IVM+IVT), doses of IVM and IVT, number of injections, follow-up time, enucleation status and side effects were recorded. Cox regression analysis and log-rank test for Kaplan-Meier curves were performed.

RESULTS

Of 77 eyes, 40 received IVM alone (group 1) and 37 received IVM+IVT (group 2). Enucleation rates were 62.5% (n=25) in group 1 and 10.8% (n=4) in group 2 (p=0.001). Median eye survival was 23.6 months in group 1 and 25.6 months in group 2. Mantel-Cox test revealed statistically significant differences between Kaplan-Meier curves of group 1 and 2 (p=0.022). Multiple Cox regression analysis showed a significantly elevated enucleation rate associated with: IVM only treatment group (p=0.019) and pre-injection cloud type of seeding (p=0.014).

CONCLUSION

The combined use of intravitreal melphalan and topotecan provides significantly better results in terms of avoiding enucleation and vitreal and subretinal seed control.

Low retinal toxicity of intravitreal carboplatin associated with good retinal tumour control in transgenic murine retinoblastoma

BACKGROUND

Retinoblastoma is a rare intraocular malignancy in children. Current treatments have many adverse effects. New therapeutic approaches like intravitreal injections of chemotherapies are currently being developed but their toxicities need to be evaluated on animal models. This study compares the efficacy and toxicity of intravitreal melphalan, topotecan and carboplatin, alone or in combination (sequential administration), in the LHBetaTag retinoblastoma mice.

METHODS

Mice were divided into nine groups: control, carboplatin 1.5 and 4 μg, melphalan 0.1 and 1 μg, topotecan 0.1 and 1 μg, carboplatin 4 μg/topotecan 0.1 μg and melphalan 1 μg/topotecan 0.1 μg. The follow-up was performed using fundus imaging and optical coherence tomography combined with histopathological analysis. Absence of tumour and presence of calcified tumours were the criteria for therapeutic response assessment. Ocular complications were assessed after four weekly injections. Retinal toxicity was defined by the decrease of retinal thickness and of the number of retinal layers.

RESULTS

Topotecan was inactive on retinal tumours. Melphalan (1 μg) led to a complete tumour control in 91.7% of eyes. Carboplatin strongly decreased the tumour burden (85.7-93.8% of eyes without retinal tumour). The intravitreal injection itself led to ocular complications (25% of media opacities and 45.7% of retinal detachment). Only melphalan at 1 μg showed a strong retinal toxicity. The two combinations showed a good efficacy in reducing the number of eyes with retinal tumours with a reduced retinal toxicity.

CONCLUSIONS

This preclinical study suggests that intravitreal injection of carboplatin has a low toxicity and could be evaluated in clinical practice to treat patients suffering from retinoblastoma.

The Interdisciplinary Diagnosis and Treatment of Intraocular Tumors

BACKGROUND

Recent years have seen major changes in the diagnosis and treatment of solid intraocular tumors, mainly owing to an improved molecular biological understanding of their pathogenesis, new therapeutic approaches for the local treatment of tumors in children, and long-term follow-up observations in clinical trials.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed.

RESULTS

Retinoblastoma is the most common type of primary intraocular tumor, with approximately 8000 new cases per year around the world, while malignant melanoma of the uvea is the most common primary intraocular tumor in adults, with approximately 7000 new cases per year around the world. Intraocular metastases of malignant tumors are ten times more common, in terms of incidence, than primary intraocular tumors and are therefore the most common intraocular tumors overall. Improved methods of intraocular biopsy, diagnostic imaging, and molecular genetic investigation have led to steady improvement in clinical and predictive diagnostic assessment. In the treatment of retinoblastoma, local techniques including brachytherapy and intra-arterial and intravitreal chemotherapy play a prominent role. Prognostic molecular-genetic testing now enables the highly selective identification of uveal melanomas that have a high potential to metastasize. Cutaneous and uveal melanomas differ both in their clinical behavior and in their basic biological features; to date, effective systemic treatment has been established for melanoma of the skin, but not for metastatic melanoma of the uvea. Intraocular metastases are common and often the initial manifestation of an extraocular tumor, particularly lung cancer.

CONCLUSION

Modern diagnostic and therapeutic concepts for intraocular tumors can only be implemented through the close interdisciplinary collaboration of ophthal - mologists, oncologists, radiologists, radiotherapists, pathologists, and human geneticists.

Heterochromia following intravitreal chemotherapy in two cases

Intravitreal chemotherapy is recognized as an effective treatment for retinoblastoma with vitreous (and occasionally subretinal) seeding refractory to intravenous or intra-arterial chemotherapy. However, this treatment carries with it the risk of toxicity to both the posterior and anterior segments of the eye, including retinal pigment epithelial mottling, ischemic/hemorrhagic retinopathy, posterior synechia, cataract, scleral necrosis, and focal iris depigmentation. We report 2 cases of iris heterochromia secondary to profound iris stromal depigmentation following intravitreal melphalan and topotecan injections.

Risk of Extraocular Extension in Eyes With Retinoblastoma Receiving Intravitreous Chemotherapy

Importance

The risk of extraocular extension from injecting chemotherapy into eyes with retinoblastoma is minimally understood; however, understanding this risk is important because of the increasing use of intravitreous chemotherapy.

Objective

To evaluate the risk of extraocular extension in eyes with retinoblastoma that have received intravitreous chemotherapy injections.

Design, Setting, and Participants

This retrospective cohort study was performed in 655 patients at 10 retinoblastoma centers in North and South American, European, Israeli, and Chinese centers. Physicians at the retinoblastoma centers administered more than 120 intravitreous chemotherapy injections in eyes with retinoblastoma from February 1, 1999, through February 28, 2017.

Main Outcomes and Measures

Risk of extraocular extension with secondary observational variables, including injection and precautionary techniques.

Results

A total of 3553 intravitreous chemotherapy injections (3201 melphalan hydrochloride, 335 topotecan hydrochloride, and 17 methotrexate sodium) were administered to 704 eyes in 655 patients with retinoblastoma (mean [SD] age of patients at the time of the initial injections, 31.6 [11.6] months; 348 male [53.1%]). There were no extraocular tumor events related to prior intravitreous injections. This finding resulted in a calculated proportion of zero extraocular events per eye. According to the rule of 3, the risk is no greater than 0.08% injections. All 10 centers included in this study used at least 2 presumed precautionary injection methods (lowering of intraocular pressure, cryotherapy, ocular surface irrigation, ultrasonic biomicroscopy surveillance of the injection site, and subconjunctival chemotherapy deposition).

Conclusions and Relevance

With use of at least 2 presumed precautionary safety methods, no extraocular extension of tumor events occurred. According to the rule of 3, this finding suggests that the risk is no greater than 0.08% injections.

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.

Ocular toxicity of intravitreal melphalan for retinoblastoma in Chinese patients

Background

To evaluate the efficacy, complications, and clinical characteristics, including the ocular toxicity, of intravitreal melphalan(IVM) treatment for vitreous seeding in Chinese retinoblastoma patients.

Methods

This was a retrospective, non-comparative analysis including 30 consecutive eyes of 23 patients with viable persistent or recurrent vitreous seeding following retinoblastoma treatment. All of the eyes received IVM injections (20–33 μg). Vitreous seeding control, determination of the ocular toxicity, and the clinical characteristics of intravitreal melphalan treatments were observed.

Results

The mean patient age at the time of the injection was 28 months (median = 22 months, range = 12–50 months). In total, 80 injections were administered in 30 eyes, the overall enucleation-free survival rate was 83.3% (25/30). The complications included retinal pigment epithelium (RPE) and choroidal atrophy (19/30, 63.3%), pupillary synechiae (13/30, 43.3%), iris atrophy (12/30, 40%), retinal vascular occlusion (12/30, 40.0%), optic atrophy (6/30, 20%), vitreous hemorrhage (3/30, 10%), persistent hypotonia and phthisis bulbi (4/30 13.3%), and cataracts (8/30, 26.6%). Twelve eyes demonstrated grade 3 or greater IVM-associated retinal or anterior segment toxicity post injection. Mean dosage given showed significant difference between the groups. There were no significant differences in the retinal toxicity grades regarding the seed classification or seed regression patterns.

Conclusions

Intravitreal melphalan is an effective treatment for refractory vitreous seeding from retinoblastoma, but exhibits both anterior and posterior segment toxicity in Chinese patients.

Lens Dose-Response Prediction Modeling and Cataract Incidence in Patients With Retinoblastoma After Lens-Sparing or Whole-Eye Radiation Therapy

PURPOSE

We retrospectively assessed the incidence of cataracts in patients with retinoblastoma (Rb) treated with either lens-sparing radiation therapy (LSRT) or whole-eye radiation therapy (WERT). A secondary aim of this study was to model the dose-response risk of cataract.

METHODS AND MATERIALS

We reviewed 65 patients with Rb treated with radiation therapy (RT) at Children's Hospital, Los Angeles from 1997 to 2015. Eyes that were enucleated before RT or lacked follow-up eye examinations were excluded. All patients underwent computed tomography simulation, and mean lens dose data were collected. Follow-up ophthalmologic examinations and intraocular lens implant history were reviewed for cataracts. The primary event-free survival (EFS) outcome was cataract development. Eyes without cataracts were censored on the last date of eye examination or post-RT enucleation, if applicable. Kaplan-Meier estimates were used to compare EFS outcomes, and dose response was projected with Cox regression and logistic regression models.

RESULTS

Sixty-one patients (94 eyes) were analyzed with a median follow-up of 51.8 months. For eyes treated with WERT, cataracts developed in 71.7% versus 35.3% for LSRT. Median EFS for WERT and LSRT were 20.8 and 67.9 months, respectively. Compared with WERT, a significant EFS benefit was demonstrated for LSRT (P < .001). Mean lens dose had a significant effect on cataracts in both Cox regression and logistic regression models (P < .01). The mean lens dose of 7 Gy was projected to have a 5-year cataract incidence of 20% and 25% with the logistic and Cox regression models, respectively.

CONCLUSIONS

We report the first clinical data demonstrating significantly improved EFS in patients with Rb treated with LSRT. Through lens dose-response modeling, we validate a mean lens dose threshold of 7 Gy to keep cataract risk below 25%. Although RT is used less often for Rb owing to advances in chemotherapy delivery options, these findings are relevant for refining lens dose constraints, particularly in children who have received radiation dose near the orbit.

Integrated Treatment during the Intravitreal Melphalan Era: Concurrent Intravitreal Melphalan and Systemic Chemoreduction

Background

Intravitreal injection of melphalan (IVM) is safe and effective for the treatment of seeding in retinoblastoma. Current protocols require weekly injections during examination under anesthesia (EUA). To avoid additional anesthesia exposure for these children, IVM was initiated at the EUA concurrent with the 4th cycle of systemic chemoreduction in a series of 6 patients with persistent seeding.

Methods

A retrospective review was completed to assess treatment response compared to all patients at our center treated with IVM and systemic chemotherapy. Overall, 6 eyes of 6 patients were included; salvage therapy included systemic chemoreduction with vincristine, etoposide, and carboplatin and IVM for persistent seeding.

Results

IVM was initiated in all eyes at cycle 4 of their chemotherapy. Success in eradicating vitreous seeds was 100%; overall salvage rate was 67%. Anterior toxicity was observed in 2 out of 6 eyes and posterior toxicity in 4 out of 6 eyes.

Conclusion

The concurrent chemoreduction and IVM protocol demonstrated a similar efficacy of globe salvage while sparing children additional EUAs. However, the increased rates of observed melphalan-related toxicities for concurrent therapy are concerning. Further clinical experience is necessary to define the best initiation time and dosing schedule for IVM.

Potential of Aqueous Humor as a Surrogate Tumor Biopsy for Retinoblastoma

Importance

Retinoblastoma (Rb) is one of the first tumors to have a known genetic etiology. However, because biopsy of this tumor is contraindicated, it has not been possible to define the effects of secondary genetic changes on the disease course.

Objective

To investigate whether the aqueous humor (AH) of Rb eyes has sufficient tumor-derived DNA to perform genetic analysis of the tumor, including DNA copy number alterations.

Design, Setting, and Participants

This investigation was a case series study at a tertiary care hospital (Children's Hospital Los Angeles) with a large Rb treatment center. Cell-free DNA (cfDNA) was isolated from 6 AH samples from 3 children with Rb, including 2 after primary enucleation and 1 undergoing multiple intravitreous injections of melphalan for vitreous seeding. Samples were taken between December 2014 and September 2015.

Main Outcomes and Measures

Measurable levels of nucleic acids in the AH and identification of tumor-derived DNA copy number variation in the AH. The AH was analyzed for DNA, RNA, and micro-RNA using Qubit high-sensitivity kits. Cell-free DNA was isolated from the AH, and sequencing library protocols were optimized. Shallow whole-genome sequencing was performed on an Illumina platform, followed by genome-wide chromosomal copy number variation profiling to assess the presence of tumor DNA fractions in the AH cfDNA of the 3 patients. One child's cfDNA from the AH and tumor DNA were subjected to Sanger sequencing to isolate the RB1 mutation.

Results

Six AH samples were obtained from 3 Rb eyes in 3 children (2 male and 1 female; diagnosed at ages 7, 20, and 28 months). A corroborative pattern between the chromosomal copy number variation profiles of the AH cfDNA and tumor-derived DNA from the enucleated samples was identified. In addition, a nonsense RB1 mutation (Lys→STOP) from 1 child was also identified from the AH samples obtained during intravitreous injection of melphalan, which matched the tumor sample postsecondary enucleation. Sanger sequencing of the AH cfDNA and tumor DNA with polymerase chain reaction primers targeting RB1 gene c.1075A demonstrated this same RB1 mutation.

Conclusions and Relevance

In this study evaluating nucleic acids in the AH from Rb eyes undergoing salvage therapy with intravitreous injection of melphalan, the results suggest that the AH can serve as a surrogate tumor biopsy when Rb tumor tissue is not available. This novel method will allow for analyses of tumor-derived DNA in Rb eyes undergoing salvage therapy that have not been enucleated.

Assessment of retinoblastoma RNA reflux after intravitreal injection of melphalan

Background

Intravitreal injection of chemotherapy in retinoblastoma eyes with vitreous seeds may lead to a risk of extraocular tumour dissemination that has not been assessed so far.

Aims

To develop a sensitive and clinically feasible technique to assess for potential retinoblastoma cell reflux after intravitreal injection of melphalan.

Methods

Filter papers were cut in 6 mm diameter circles and sterilised before use. Eyes with retinoblastoma vitreous seeds (group D, International Classification) received weekly intravitreal melphalan injections (20 µg or 30 µg/dose) followed by cryotherapy as part of local treatment. Immediately after finishing the injection and cryotherapy, filter papers were placed on the injection site and on the cryoprobe tip to assess for the expression of the cone-rod homeobox gene (CRX) by real-time qPCR as a surrogate of retinoblastoma RNA. The assay was developed and validated to determine sensitivity, linearity, recovery, repeatability and reproducibility.

Results

The assay for quantitation of CRX expression was linear in the range of 1 to 1000 cells. The lowest limit of detection was one retinoblastoma cell and allowed to recover 100% of the cell load in external supplementation. A total of 14 eyes received 22 cycles of intravitreal melphalan and were evaluated for potential extraocular tumour cell dissemination using the developed technique. None of the cycles were positive for CRX in samples from the scar or from the cryoprobe tip.

Conclusions

A sensitive and simple method of tumour cell assessment has been developed that can be used in the clinics to assess for potential extraocular dissemination after intravitreal injections to assure its performance.

Vitreous Seeds in Retinoblastoma: Clinicopathologic Classification and Correlation

PURPOSE

A recent classification scheme for retinoblastoma vitreous seeds has shown promise in predicting treatment response. For the first time, we correlate this clinical classification scheme with its histopathologic features.

DESIGN

Retrospective review.

PARTICIPANTS

Enucleated eyes received at the pathology department of the Retinoblastoma Center of Houston from 2010 to 2015.

METHODS

Macroscopic photographs of the enucleated eyes of patients with retinoblastoma were analyzed to select those with vitreous seeds. Cases with adequate material for clinicopathologic correlation were selected for further analysis, and clinical photographs were reviewed. Routine histopathologic slides were reviewed and compared with the clinical and macroscopic photographs. Seeds were classified as type 1 ("dust"), type 2 ("sphere"), or type 3 ("cloud"). To confirm the presence of macrophages, CD68 immunohistochemical staining was used. Synaptophysin was used to stain retinoblastoma cells.

MAIN OUTCOME MEASURES

To correlate clinical vitreous seed type with histopathologic features.

RESULTS

A total of 14 eyes with adequate amounts of tumor seeds along with clinical and macroscopic photographic correlation were selected from a total of 138 eyes reviewed. Type 1 seeds consisted of individual viable tumor cells and scattered macrophages. Type 2 seeds consisted of 2 submorphologies: spheres with viable cells throughout and spheres with an outer rim of viable cells but necrotic cells centrally. Type 3 seeds were composed of more than 90% necrotic material admixed with few macrophages and viable cells at their outer rim. Untreated (8/14) and previously treated (6/14) eyes showed similar histopathologic features for each type of seeds. Treated eyes had more type 1 and 3 seeds.

CONCLUSIONS

We provide the first histopathologic correlation of the clinical classification scheme for vitreous seeds in retinoblastoma. "Dust" is formed by scattered single cells alternating with macrophages. "Spheres" with translucent centers contain multiple layers of viable tumor cells that shed single cells and may be more clinically aggressive. "Cloud" seeds are mostly composed of necrotic material, explaining their lack of therapeutic response. Pretreated eyes showed tumor seeds morphologically similar to untreated eyes. Knowledge of the underlying histopathology of vitreous seed types is a fundamental component of classification and may aid in understanding clinical response to treatment.

Intraocular Pressure Changes Following Intravitreal Melphalan and Topotecan for the Treatment of Retinoblastoma With Vitreous Seeding

PURPOSE

To investigate the impact of intravitreal chemotherapy on intraocular pressure (IOP) in children with retinoblastoma.

METHODS

This was a retrospective study of 10 eyes of 10 patients with retinoblastoma (7 males, 3 females, mean age: 33.6 ± 9.4 months) with vitreous seeding injected with intravitreal melphalan and topotecan. IOP was measured with Tonopen (Reichert, Inc., Buffalo, NY) at baseline prior to injecting and then repeatedly following each intravitreal injection.

RESULTS

Mean pre-injection IOP was 8.2 ± 2.3 mm Hg (range: 4 to 12 mm Hg). Mean IOP 1 to 30 seconds after intravitreal melphalan (first injection) was 45.4 ± 14.3 mm Hg. The IOP of 89.5% of patients declined to 29 mm Hg or less in a mean 153.3 ± 97.5 seconds. Mean IOP 1 to 30 seconds after intravitreal topotecan (second injection) was 44.5 ± 11.0 mm Hg, which decreased to 31.0 ± 5.0 mm Hg by 150 seconds after injection. No significant relationship was found between age and post-injection IOP elevation. IOP exceeded the calculated mean arterial perfusion pressure in four encounters.

CONCLUSIONS

Intravitreal chemotherapy caused a transient rise in IOP. Post-injection IOP elevations can reach levels that may exceed mean arterial pressure. [J Pediatr Ophthalmol Strabismus. 2017;54(3):185-190.].

Intravitreal chemotherapy in the management of vitreous disease in retinoblastoma

PURPOSE

To evaluate the therapeutic outcome of intravitreal melphalan injection in the management of vitreous disease in patients with retinoblastoma. We particularly aimed to assess whether higher melphalan dose with lower number of injections was more effective and associated with fewer side effects.

METHODS

This retrospective, interventional, noncomparative, and nonrandomized study included 39 eyes of 37 patients. Vitreous seeds were classified as dust, sphere, and cloud types. Intravitreal injections were performed through pars plana free of any visible tumor using 30-G needle. Response of the seeds (disappearance, conversion into inactive debris, or progression) and enucleation rate were determined as outcome measures.

RESULTS

All patients previously received systemic or intra-arterial chemotherapy. Vitreous seeding was primary in 54% of eyes and secondary in 46% of eyes. Vitreous seeds were classified as dust in 9 (23.1%) eyes, sphere in 24 (61.5%) eyes, and cloud in 6 (15.4%) eyes. Melphalan dose varied between 20 and 40 µg and 20 (51.3%) eyes received >30 µg. The total number of injections was 70 (range 1-5, mean 1.8 per eye). Various types of regression were obtained in 27 (69.2%) eyes. Sphere-type seeds were the most responsive to melphalan. Nonresponse and disease progression were noted in 12 (30.8%) eyes. After a mean follow-up of 11.8 months, 17 (44%) eyes were enucleated. Vitreous hemorrhage (18%) and retinal pigment epithelial alterations (8%) were the most common side effects.

CONCLUSIONS

Intravitreal melphalan at 30-40 µg in 1 or 2 injections proved effective in 69.2% of eyes with vitreous disease.

Acute Hemorrhagic Retinopathy following Intravitreal Melphalan Injection for Retinoblastoma: A Report of Two Cases and Technical Modifications to Enhance the Prevention of Retinal Toxicity

AIMS

To report the occurrence of acute hemorrhagic retinopathy following intravitreal melphalan injection for retinoblastoma.

METHODS

This is a retrospective case series of 2 patients with retinoblastoma treated with intravitreal melphalan for vitreous seeding who developed acute hemorrhagic retinopathy.

RESULTS

Patient 1 is a 6-month-old female with bilateral retinoblastoma (Group D right eye and Group B left eye) treated with 4 cycles of systemic chemotherapy and 2 intravitreal melphalan injections in each eye. Patient 2 is a 10-month-old male with unilateral Group D retinoblastoma treated with 6 cycles of systemic chemotherapy and 2 injections of intravitreal melphalan. At the 1-week follow-up after the second injection, both patients had an acute hemorrhagic retinopathy that resulted in chorioretinal toxicity with a sharp demarcation line between the normal and abnormal retina. At the last follow-up (22 and 12 months, respectively), there was total tumor control and resolution of vitreous seeding in both patients.

CONCLUSIONS

Although intravitreal melphalan injection is effective for vitreous seeding in eyes with retinoblastoma, acute hemorrhagic retinopathy and diffuse chorioretinal atrophy is a possible complication of this treatment modality. Given the clinical findings observed in these patients, the development of this retinal toxicity most likely results from a retrohyaloid overdose. Consequently we suggest preventive measures aimed at limiting the risk of retrohyaloid injection.

Highlights from the 1st Latin American meeting on metronomic chemotherapy and drug repositioning in oncology, 27-28 May, 2016, Rosario, Argentina

Following previous metronomic meetings in Marseille (2011), Milano (2014), and Mumbai (2016), the first Latin American metronomic meeting was held in the School of Medical Sciences, National University of Rosario, Rosario, Argentina on 27 and 28 of May, 2016. For the first time, clinicians and researchers with experience in the field of metronomics, coming from different countries in Latin America, had the opportunity of presenting and discussing their work. The talks were organised in three main sessions related to experience in the pre-clinical, and clinical (paediatric and adult) areas. The different presentations demonstrated that the fields of metronomic chemotherapy and repurposing drugs in oncology, known as metronomics, constitute a branch of cancer therapy in permanent evolution, which have strong groups working in Latin

America, both in the preclinical and the clinical settings including large, adequately designed randomised studies. It was shown that metronomics offers treatments, which, whether they are combined or not with the standard therapeutic approaches, are not only effective but also minimally toxic, with the consequent improvement of the patient’s quality of life, and inexpensive, a feature very important in low resource clinical settings. The potential use of metronomic chemotherapy was proposed as a cost/effective treatment in low-/middle-income countries, for adjuvant therapy in selected tumours. The fundamental role of the governmental agencies and non-governmental alliances, as the Metronomic Global Health Initiative, in supporting this research with public interest was underlined.