The Potential of Aqueous Humor Sampling in Diagnosis, Prognosis, and Treatment of Retinoblastoma.

Retinoblastoma (RB) is a rare malignant tumor that arises in the developing retina in one or both eyes of children. Pathogenic variants of the RB1 tumor suppressor gene drive the majority of germline and sporadic RB tumors. Considering the risk of tumor spread, the biopsy of RB tumor tissue is contraindicated. Advancement of chemotherapy has led to preservation of more eye globes. However, this has reduced access to tumor material from enucleation specimens. Recently, liquid biopsy of aqueous humor (AH) has advanced the RB tumor- or eye-specific genetic analysis. In particular, nucleic acid analysis of AH demonstrates the genomic copy number profiles and RB1 pathogenic variants akin to that of enucleated RB eye tissue. This advance reduces the previous limitation that genetic assessment of the primary tumor could be done only after enucleation of the eye. Additionally, nucleic acid evaluation of AH allows the exploration of the genomic landscape of RB tumors at diagnosis and during and after treatment. This review explores how AH sampling and AH nucleic acid analysis in RB patients assist in diagnosis, prognosis, and comprehending the pathophysiology of RB, which will ultimately benefit individualized treatment decisions to carefully manage this ocular cancer in children.

Child eye health in Ethiopia: a mixed methods analysis of policy and commitment to action.

BACKGROUND: Child eye health is a serious public health issue in Ethiopia, where children under the age of 15 account for over half of the population. Our aim was to review Ethiopian health policy and practice to reveal approaches and commitment to promotion and delivery of child eye health services. METHODS: We conducted a mixed-methods situational analysis employing documentary analysis and key informant interview methods. Government publications touching on any element of child eye health were included. Key informants were eligible if they were leaders, authorities, researchers or clinicians involved in child health. Data was combined and analysed by narrative synthesis, using an adaptation of the Eye Care Situation Analysis Tool as a framework. FINDINGS: Eleven documents developed by the Ministries of Health and Education were included and interviews with 14 key informants were conducted. A focus on child eye health was lacking in key health policy documents, demonstrated by limited allocation of funds, a shortage of human resources, and a subpar referral system across all levels of child eye care. CONCLUSION: The study identified several gaps and limitations in child eye health in Ethiopia. There is a need for health policies that strengthen ownership, finance and partnerships for improved coordination, and collaboration with line ministries and other stakeholders to improve child eye health services in Ethiopia.

Exploring the knowledge, attitudes, and practice towards child eye health: A qualitative analysis of parent experience focus groups.

BACKGROUND: The majority of childhood blindness causes in low-income countries are treatable or avoidable. Parents or guardians are responsible for making decisions regarding a child's eye care. Understanding parents' awareness and perception of eye problems in crucial in helping to know parents' eye care-seeking behavior. OBJECTIVE: To determine parental knowledge, attitudes and practice regarding child eye health. METHODS: Seven focus groups were carried out in Northwest Ethiopia on knowledge, attitude and practice of parents towards child eye health. Their responses were tape-recorded and later transcribed. A thematic phenomenological approach was used for the analysis. RESULT: Seventy-one parents participated in the focus groups. Participants were aware of common eye problems like trachoma, trauma, and glaucoma. However, they were unaware of the causes and etiologies of childhood blindness. Participants perceived that eye problems could be treated with hygiene and food, and often held misconceptions about the cause of strabismus and utilization of wearing spectacles. CONCLUSION: The study revealed that parents are often unaware of the causes and etiologies of common childhood eye diseases, which has downstream effects on health-seeking behavior. Health promotion efforts, potentially through mass and social media, could be helpful to raise awareness, coupled with training of health professionals at primary and secondary health facility levels.

Social Determinants of Health in Pediatric Ophthalmology Patients: Availability of Data in the Electronic Health Record and Association With Clinic Attendance.

Purpose: To characterize the availability of social determinants of health data in the electronic health record of pediatric ophthalmology patients and to examine the association of social determinants of health with attendance at scheduled operating room and clinic visits. Methods: This was a retrospective cohort study of pediatric ophthalmology patients seen at The Hospital for Sick Children between June 1, 2018, and May 23, 2022. Data were collected on demographics, diagnosis, and management-plan. The χ2 tests and multivariable regression were used to examine associations between social determinants of health and attendance at scheduled operating room and clinic visits. Results: The cohort consisted of 26,102 study subjects with 31,288 unique eye-related diagnoses representing 57 unique ICD-10 codes. Availability of data in the electronic health record ranged from 100% for sex, age and postal code to 0.1% for ethnic group. Female sex (P = 0.004) and urbanicity (P = 0.05) were associated with higher operating room visit cancellations. Female sex (P = 0.002), age group 0-13 (P ≤ 0.001), low-medium neighborhood income quintile (P ≤ 0.001), residence of Northern Ontario (P ≤ 0.001), and urbanicity (P ≤ 0.001) were associated with higher clinic visit cancellations and no-shows. Conclusions: At a major tertiary-care hospital in Canada, key social determinant data such as ethnicity are not consistently available in the electronic health record of pediatric ophthalmology patients. Female sex, younger age, and living in a rural area or neighborhood with low-medium income quintile may be predictors of missed visits and require further study. Translational Relevance: This study highlights a need for improved documentation of social determinants of health variables in electronic health records.

Health Services Needs Assessment for Retinoblastoma in Ethiopia.

PURPOSE: The aim of this study was to document the available resources and needs for the detection, diagnosis, and treatment of retinoblastoma (RB) in Ethiopia. METHODS: A health services needs assessment focused on RB care in Ethiopia was conducted. Information was obtained through a web-based survey and field visits. Facilities offering RB service delivery were categorized into three tiers, on the basis of the ability to detect (tier 1) and manage simple (tier 2) or complex (tier 3) patients with RB. Descriptive statistics were performed to quantify human and material resources available at each facility. RESULTS: The web survey received 29 responses from ophthalmologists at 19 health care facilities. Of the 19 units surveyed, seven (36.8%) had an ophthalmologist dedicated to RB treatment, classifying them as either a tier 2 or 3 facility. All tier 3 facilities had an affiliated health facility offering access to off-site pediatric oncology and pathology services. Of the focal therapies offered at tier 3 facilities, none included local chemotherapy or brachytherapy. Enucleation was offered at all tier 2 facilities, but availability of orbital implants and ocular prostheses was variable. None of the health facilities offered genetics services. CONCLUSION: This study demonstrated that the human and material resources needed for RB care in Ethiopia are constrained. Tier 3 RB facilities are rare and concentrated in urban areas, which could make it difficult for many patients to access. With focused capacity-building efforts, it is possible to increase the efficiency of RB therapy.

Incidence and geographic distribution of retinoblastoma in Ethiopia.

INTRODUCTION: Retinoblastoma is the most frequent intraocular malignancy of the eye in children, occurring in early childhood. Based on global estimates, Ethiopia is expected to observe over 200 new retinoblastoma cases per year, however without a cancer registry, this number is difficult to confirm. Therefore, the goal of the study was to determine the incidence and geographic distribution of retinoblastoma in Ethiopia. METHODS: A retrospective medical chart review of clinically diagnosed new retinoblastoma patients between January 1, 2017 - December 31, 2020, in four public Ethiopian tertiary hospitals was performed. The incidence of retinoblastoma was calculated by a birth-cohort analysis. RESULTS: There were 221 retinoblastoma patients observed in the study period. The incidence of retinoblastoma was found to be 1 in 52,156 live births. Incidence varied among different regions of Ethiopia. CONCLUSION: The incidence of retinoblastoma observed in this study is likely an underestimate. It is possible that patients were undercounted because they were seen outside of the 4 main retinoblastoma treatment facilities included in this facility, or they experienced barriers to accessing care. Our study suggests a need for a nationwide retinoblastoma registry and more retinoblastoma treatment centers in the country.

Referral patterns for retinoblastoma patients in Ethiopia.

BACKGROUND: Increased lag time between the onset of symptoms and treatment of retinoblastoma (RB) is one of the factors contributing to delay in diagnosis. The aim of this study was to understand the referral patterns and lag times for RB patients who were treated at Menelik II Hospital in Addis Ababa, Ethiopia. METHOD: A single-center, cross- sectional study was conducted in January 2018. All new patients with a confirmed RB diagnosis who had presented to Menelik II Hospital from May 2015 to May 2017 were eligible. A questionnaire developed by the research team was administered to the patient's caregiver by phone. RESULTS: Thirty-eight patients were included in the study and completed the phone survey. Twenty-nine patients (76.3%) delayed seeing a health care provider for ≥ 3 months from the onset of symptoms, with the most common reason being the belief that it was not a problem (96.5%), followed by 73% saying it was too expensive. The majority of patients (37/38, 97.4%) visited at least 1 additional health care facility prior to reaching a RB treatment facility. The mean overall lag time from noticing the first symptom to treatment was 14.31 (range 0.25-62.25) months. CONCLUSION: Lack of knowledge and cost are major barriers to patients first seeking care for RB symptoms. Cost and travel distance are major barriers to seeing referred providers and receiving definitive treatment. Delays in care may be alleviated by public education, early screening, and public assistance programs.

Caring for a child with retinoblastoma: Experience of Ethiopian parents.

OBJECTIVE: This study explored the lived experience of parents of children with retinoblastoma. DESIGN AND METHOD: A phenomenological qualitative study design was used, and a purposive sampling technique to recruit parents of children with retinoblastoma. Semi-structured interviews were conducted to document the lived experience of participants, who were asked to narrate their experiences caring for a child with retinoblastoma, thinking back to the day they learned about their child's condition, as well as their thoughts about the future. The interviews were conducted in Amharic and Oromo language, and audio recordings were transcribed and translated to English. Data were analyzed using thematic analysis. RESULTS: Thirteen parents (seven mothers, six fathers) participated in the study. Collectively, the children of the participants represented all the stages of the retinoblastoma journey (i.e., diagnosis, treatment, remission, and recurrence). Five major themes emerged from the thematic data analysis: (a) reactions when learning the child's condition; (b) receiving health care; (c) costs of caregiving; (d) support; and (e) uncertainties. CONCLUSION: The lived experiences of parents of children with retinoblastoma revealed a significant mental health and psychosocial burden. The sources of mental distress were found to be complex and varied. Holistic care for retinoblastoma should include programs that address the biopsychosocial needs of caregivers.

EMPOWER Retinoblastoma: Engaging Patient Partners in Solving the Top 10 Priorities for Eye Cancer Research in Canada.

While it is recognized that research priorities should reflect and integrate the perspectives and needs of patients along with those of health professionals and researchers, it remains challenging to actualize such priorities into tangible research projects. Targeted dissemination is required to catalyze research on these priorities. To create awareness of and inspire action toward actualizing the top 10 retinoblastoma research priorities in Canada, Canadian Retinoblastoma Research Advisory Board (CRRAB) members developed a wide range of dissemination tools and processes. These resources, co-produced with patients, were instrumental to CRRAB sharing the top 10 priorities internationally to mobilize action toward solving them.

The Retinoblastoma Research Booklet: A Catalyst for Patient Involvement in Retinoblastoma Research.

Peer-to-peer recruitment efforts are important in generating interest and participation of patients as partners in research but difficult to sustain when face-to-face interactions are limited. The Retinoblastoma Research and You! booklet, co-developed by patients, researchers and health professionals, serves as a guide for patient engagement in research while retaining an element of personalization. The Retinoblastoma Research and You! booklet was developed through two virtual workshops to iterate and finalize the booklet design and content. The booklet outlines how individual patients' lived experiences and skills can influence retinoblastoma research and highlights real-world examples of patient-partnered research activities at different stages of the research process.

Values of Retinoblastoma Survivors and Parents Regarding Treatment Outcomes: A Qualitative Study.

PURPOSE: Retinoblastoma is an aggressive pediatric eye cancer. Patient-reported outcome measures reveal important insights into how patients perceive their own health. Currently, there is no widely used or validated measure for assessment of retinoblastoma outcomes. The purpose of this research was to uncover which treatment outcomes that retinoblastoma survivors and their parents value, to inform the development of a future measure. METHODS: This qualitative, cross-sectional study included retinoblastoma survivors age 6 years and older and parents of retinoblastoma survivors. Participants who did not demonstrate fluency in English were excluded. Study participants participated in semistructured interviews or focus groups, either in person at The Hospital for Sick Children, Toronto, Canada, or through secure videoconference, between March 3, 2019, and January 25, 2020. Iterative rounds of opening coding, codebook development, and coresearcher analysis were used to identify key emergent themes and subthemes. RESULTS: Seventeen adults participated in six focus groups. Nine pediatric survivors participated in individual interviews. Four common themes emerged from all participant groups: (1) definition of treatment success, (2) enucleation-acceptance and challenges, (3) treatment outcomes to measure, and (4) need for outcome reporting. An additional, unique theme was identified in all pediatric discussions: worries and coping mechanisms. Treatment outcomes deemed valuable were related to the following domains: psychosocial outcomes, daily functioning, functional vision, retinoblastoma education, cosmetic outcomes, and secondary eye conditions. CONCLUSION: This study represents the first stage in the development of a retinoblastoma-specific patient-reported outcome measure. The findings reveal insight into what outcomes are valued by survivors after treatment and offer promise to improve outcomes assessment for retinoblastoma.

Clinicopathological Presentation of Retinoblastoma in Ethiopia.

Introduction: The presenting symptoms of retinoblastoma in Ethiopia, as well as their relationship to the stage of the disease, are poorly understood, but they could be important as background knowledge for creating early detection initiatives. This study aimed to describe the clinical and histopathological characteristics of retinoblastoma among Ethiopian patients. Methods: A hospital-based cross-sectional analysis of all children with newly diagnosed retinoblastoma during the study period of May 2015 to December 2019, inclusive, who presented to a tertiary referral center during were included. Demographic, clinical, and histological characteristics were collected and descriptive statistics were done using SPSS Version 20.0 software. Results: A total of 217 patients (unilateral 84.3%, bilateral 15.7%) were studied. The median age at presentation was 29 months (34 months vs. 19.5 months in unilateral and bilateral cases, respectively, p < 0.001). Among all patients, 57.8% were male. Leukocoria was the most common presenting sign (37.3%) and followed by fungating mass (31.8%). Tumors were extraocular in 40.1% of cases. From the intraocular cases, 73.3% were advanced International Intraocular Retinoblastoma Classification Group D or E disease. Sixty-two (54.4%) of the eyes had high-risk pathological features. The median lag time was significantly shorter for intraocular versus extraocular cases (5 months vs. 12 months, respectively, p < 0.001). Conclusion: Our results show that the majority of Ethiopian children with retinoblastoma have delayed presentation and late stage at diagnosis. This suggests that national health promotion campaigns to increase public knowledge on the presenting signs of retinoblastoma may be critical to achieving early diagnosis. Furthermore, the development of standard management guidelines informed by this study will be helpful in managing the complex and advanced cases currently observed.

Asynchronous pineoblastoma is more likely after early diagnosis of retinoblastoma: a meta-analysis.

PURPOSE: To determine the risk of patients with an early diagnosis of heritable retinoblastoma being diagnosed with TRb (or pineoblastoma) asynchronously in a later stage and its effect on screening. METHODS: We updated the search (PubMed and Embase) for published literature as performed by our research group in 2014 and 2019. Trilateral retinoblastoma (TRb) patients were eligible for inclusion if identifiable as unique and the age at which TRb was diagnosed was available. The search yielded 97 new studies. Three new studies and eight new patients were included. Combined with 189 patients from the previous meta-analysis, the database included 197 patients. The main outcome was the percentage of asynchronous TRb in patients diagnosed before and after preset age thresholds of 6 and 12 months of age at retinoblastoma diagnosis. RESULTS: Seventy-nine per cent of patients with pineoblastoma are diagnosed with retinoblastoma before the age of 12 months. However, baseline MRI screening at time of retinoblastoma diagnosis fails to detect the later diagnosed pineal TRb in 89% of patients. We modelled that an additional MRI performed at the age of 29 months picks up 53% of pineoblastomas in an asymptomatic phase. The detection rate increased to 72%, 87% and 92%, respectively, with 2, 3 and 4 additional MRIs. CONCLUSIONS: An MRI of the brain in heritable retinoblastoma before the age of 12 months misses most pineoblastomas, while retinoblastomas are diagnosed most often before the age of 12 months. Optimally timed additional MRI scans of the brain can increase the asymptomatic detection rate of pineoblastoma.

Clinical audit of retinoblastoma management: a retrospective single-institution study.

OBJECTIVE: The primary aim of this study was to identify the frequency of death, metastasis, enucleation, and use of external beam radiation therapy (EBRT) among retinoblastoma patients. The secondary aim was to determine whether any events were associated with suboptimal clinical management to identify areas for clinical care improvement. METHODS: Patients diagnosed with retinoblastoma between January 1, 2000, and December 31, 2015, at The Hospital for Sick Children were included. Medical records of eligible patients underwent a comprehensive 2-part review. First, a chart review collected diagnostic details, treatment course, and occurrence of 4 events: death, metastasis, use of EBRT, and enucleation. Next, events were reviewed in detail, and a multidisciplinary committee reached consensus on cases managed suboptimally. RESULTS: The study included 209 patients (292 eyes). There were 8 deaths, 11 metastases, 177 enucleations (143 primary, 34 secondary), and 8 uses of EBRT. Thirteen patients were reviewed by the multidisciplinary committee, which confirmed that 5 of these patients had events associated with suboptimal clinical management. Three patients developed metastases leading to death (misdiagnosis and mismanagement of trilateral retinoblastoma [1], parental refusal of enucleation [1], and inaccurate histopathology after primary enucleation [1]). One patient developed extraocular extension related to scleral invasion following aggressive focal therapy. One patient underwent secondary enucleation for a Group B eye related to mismanagement of a treatment complication. DISCUSSION: Deaths, metastases, and enucleations with documented instances of suboptimal care highlighted a need to enhance medical team and patient communication, histopathology interpretation, laser treatment guidelines, and trilateral retinoblastoma management. Routine clinical audit of retinoblastoma management can identify areas for clinical practice change.

Patient preferences in retinal drug delivery.

Retinal vascular diseases (RVDs) are often treated with intravitreally (IVT) injected drugs, with relatively low patient compliance and potential risks. Ongoing research explores alternative RVD treatments, including eye drops and oral tablets. This study surveyed RVD patients treated with IVT injections to establish factors influencing low compliance rates while gauging treatment delivery method preferences. Demographics, perspectives, and treatment preferences were collected via IRB-approved, self-administered survey sent to Glick Eye Institute patients treated via IVT injections. Demographics, diagnoses, and treatments were ascertained from respondents' medical records. Gender, age, and number of IVT injections received were used as stratifications. Five-level Likert-style scales and t-tests evaluated responses and stratification comparisons. The most common diagnoses in the respondent population (n = 54; response rate = 5%) were age-related macular degeneration, macular edema, and diabetic retinopathy. Respondents had varying levels of education, income, and age. Most (83%) admitted feeling anxious prior to their first IVT injection, but 80% reported willingness to receive IVT injections indefinitely, with a preference for ophthalmologist visits every 1-3 months. Eye drops would be preferred over IVT injections by 76% of respondents, while 65% preferred oral tablets, due to several perceived negative factors of IVT injections and positive factors for eye drops. Stratified groups did not differ in responses to survey questions. RVD patients will accept IVT injections for vision preservation, but alternative delivery methods like eye drops or oral tablets would be preferred. Thus, development of eye drop and oral therapeutics for RVD treatment is further emphasized by these findings.

Binary pan-cancer classes with distinct vulnerabilities defined by pro- or anti-cancer YAP/TEAD activity.

Cancer heterogeneity impacts therapeutic response, driving efforts to discover over-arching rules that supersede variability. Here, we define pan-cancer binary classes based on distinct expression of YAP and YAP-responsive adhesion regulators. Combining informatics with in vivo and in vitro gain- and loss-of-function studies across multiple murine and human tumor types, we show that opposite pro- or anti-cancer YAP activity functionally defines binary YAPon or YAPoff cancer classes that express or silence YAP, respectively. YAPoff solid cancers are neural/neuroendocrine and frequently RB1-/-, such as retinoblastoma, small cell lung cancer, and neuroendocrine prostate cancer. YAP silencing is intrinsic to the cell of origin, or acquired with lineage switching and drug resistance. The binary cancer groups exhibit distinct YAP-dependent adhesive behavior and pharmaceutical vulnerabilities, underscoring clinical relevance. Mechanistically, distinct YAP/TEAD enhancers in YAPoff or YAPon cancers deploy anti-cancer integrin or pro-cancer proliferative programs, respectively. YAP is thus pivotal across cancer, but in opposite ways, with therapeutic implications.

Opportunities and barriers for genetic service delivery in Kenya from a health personnel perspective.

Genetic counselling and testing are essential health services for the management of heritable diseases. However, in low-and-middle income countries like Kenya, genetic counsellors are not yet a licenced profession, and there is limited availability of and access to genetic testing. This study aimed to uncover opportunities and barriers for genetic service delivery in the Kenyan healthcare system from the perspectives of those who provide genetic testing and/or genetic counselling. Participants included Kenyan health personnel who deliver genetic services. This was a qualitative study that collected data via semi-structured one-on-one interviews and analyzed it using inductive thematic analysis. Participant demographics and characteristics of clinical genetic service provision were collected using a survey and results summarized using descriptive statistics. Themes revealed during analysis were compared to the clinical characteristics of genetic service provision to inform the opportunities and barriers. Fifteen interviews were conducted in total. Thematic analysis indicated that participants believed that the barriers facing genetic service delivery were linked to three themes: (1) education and training, (2) costs, and (3) counselling challenges. The opportunities for genetic service delivery were linked to four themes: (1) demand, (2) education and training, (3) encouraging a multidisciplinary approach to care, and (4) enhancing laboratory infrastructure. These findings are crucial for the development of a national evidence-informed and culturally appropriate model for genetic service delivery.

Defining Clinical Public Health.

PURPOSE: To solve complex health issues, an innovative and multidisciplinary framework is necessary. The Clinical Public Health (CPH) Division was established at the University of Toronto (UofT), Canada to foster inte-gration of primary care, preventive medicine and public health in education, practice and research. To better understand how the construct of CPH might be applied, we surveyed clinicians, researchers and public health professionals affiliated with the CPH Division to assess their understanding of the CPH concept and its utility in fostering broad collaboration. METHODS: A two-wave anonymous survey of the active faculty of the CPH Division, UofT was conducted across Canada. Wave 1 participants (n = 187; 2016) were asked to define CPH, while Wave 2 participants (n = 192; 2017) were provided a synthesis of Wave 1 results and asked to rank each definition. Both waves were asked about the need for a common definition, and to comment on CPH. RESULTS: Response rates for the first and second waves were 25% and 22%, respectively. Of the six definitions of CPH from Wave 1, "the intersection of clinical practice and public health," was most highly ranked by Wave 2 participants. Positive perceptions of CPH included multidisciplinary collaboration, new fields and insights, forward thinking and innovation. Negative perceptions included CPH being a confusing term, too narrow in scope or too clinical. CONCLUSION: The concept of Clinical Public Health can foster multidisciplinary collaboration to address com-plex health issues because it provides a useful framework for bringing together key disciplines and diverse professional specialties.

Ethical, social, and cultural issues related to clinical genetic testing and counseling in low- and middle-income countries: a systematic review.

PURPOSE: We performed a systematic review of the ethical, social, and cultural issues associated with delivery of genetic services in low- and middle-income countries (LMICs). METHODS: We searched 11 databases for studies addressing ethical, social, and/or cultural issues associated with clinical genetic testing and/or counselling performed in LMICs. Narrative synthesis was employed to analyze findings, and resultant themes were mapped onto the social ecological model (PROSPERO #CRD42016042894). RESULTS: After reviewing 13,308 articles, 192 met inclusion criteria. Nine themes emerged: (1) genetic counseling has a tendency of being directive, (2) genetic services have psychosocial consequences that require improved support, (3) medical genetics training is inadequate, (4) genetic services are difficult to access, (5) social determinants affect uptake and understanding of genetic services, (6) social stigma is often associated with genetic disease, (7) family values are at risk of disruption by genetic services, (8) religious principles pose barriers to acceptability and utilization of genetic services, and (9) cultural beliefs and practices influence uptake of information and understanding of genetic disease. CONCLUSION: We identified a number of complex and interrelated ethical, cultural, and social issues with implications implications for further development of genetic services in LMICs.

Characterization of international partnerships in global retinoblastoma care and research: A network analysis.

Global cooperation is an integral component of global health research and practice. One Retinoblastoma World (1RBW) is a cooperative network of global treatment centers that care for children affected by retinoblastoma. The study aimed to determine the number, scope and nature of collaborations within 1RBW, and uncover how they are perceived to contribute towards improving retinoblastoma outcomes. A cross-sectional, mixed-methods egocentric network analysis was conducted. Treatment centers (n = 170) were invited to complete an electronic survey to identify collaborative activities between their institution (ego), and respective partners (alters). Network maps were generated to visualize connectivity. Key informants (n = 18) participated in semi-structured interviews to add details about the reported collaborations. Interviews were analysed through inductive thematic analysis. Surveys were completed by 56/170 (33%) of 1RBW treatment centers. Collectively, they identified 112 unique alters (80 treatment centers; 32 other organizations) for a total network size of 168 nodes. Most collaborations involved patient referrals, consultations and twinning/capacity building. Interviews identified four main themes: conceptualization of partnership; primary motivation for collaborations; common challenges to collaboration; and benefits to partnership. There is extensive global collaboration to reduce global retinoblastoma mortality, but there is room to expand connectivity through active efforts to include actors located at network peripheries.