Bilateral advanced (group D or E) intraocular retinoblastoma: outcomes in 72 Asian Indian patients

Management of Intraocular Retinoblastoma: ICMR Consensus Guidelines

Retinoblastoma (RB) is the most common childhood intraocular malignancy. Delayed presentation due to a lack of awareness and advanced intraocular tumors are a common scenario in low-middle income countries (LMICs). Remarkable treatment advances have been made in the past few decades allowing globe salvage in advanced intraocular RB (IORB) including systemic chemotherapy with focal consolidation and targeted treatments like intraarterial chemotherapy and intravitreal chemotherapy. However, a lack of availability and affordability limits the use of such advances in LMICs. External beam radiotherapy, despite risk of second cancers in RB with germline mutations, still remains useful for recalcitrant RB not responding to any other treatment. When choosing conservative treatment for advanced IORB, the cost and long duration of treatment, morbidity from multiple evaluation under anesthesias (EUAs), side effects of treatment and risk of treatment failure need to be taken into account and discussed with the parents. In this article, the authors discuss the ICMR consensus guidelines on the management of IORB.

Clinicodemographic profile, management, and treatment outcomes in advanced retinoblastoma at a tertiary care center in North India

PURPOSE

The study was undertaken to look into the clinicodemographic profile, management, and clinical outcomes of advanced retinoblastoma at a tertiary care center.

METHODS

A prospective cohort study was conducted from Jan 2019 to Dec 2022. Forty-two patients of intraocular advanced retinoblastoma were assessed. The treatment protocol was formulated based on size, extension of tumor, and laterality. Primary outcome measure was response to the treatment in terms of regression of tumor and seeds and no evidence of recurrence after 12 month in enucleated eyes. Secondary outcome measures were complications like implant exposure, metastasis, and death associated with each treatment modality.

RESULTS

The mean age of the study group was 13 months. The most common presentation was leukocoria with diminished vision. Most of the patients had group E retinoblastoma ( n = 40, 95%) as per the International Classification of Retinoblastoma. In 12 patients with group E retinoblastoma, primary enucleation was performed and in six patients, secondary enucleation was done, in which initially, globe salvage treatment was tried. In 30 patients, globe salvage treatment was attempted and we could manage to save 23 eyes. The most common treatment modality was intra-arterial chemotherapy using a triple-drug regimen. One patient developed intracranial spread and died due to systemic metastasis during the follow-up period.

CONCLUSION

The current study showed that globe salvage is possible in advanced retinoblastoma if appropriate therapy is instituted depending upon the extent of the tumor and availability of latest treatment modalities. Intra-arterial chemotherapy using triple drugs can be offered as a first-line therapy in advanced unilateral retinoblastoma as it has been found to be very effective in the present study.

Antitumoral Potential of the Histone Demethylase Inhibitor GSK-J4 in Retinoblastoma

Purpose

The purpose of this study was to investigate the antitumor effects of GSK-J4 on retinoblastoma, as well as its related biological functions and molecular mechanisms.

Methods

The antitumor effect of GSK-J4 on retinoblastoma was evaluated by in vitro and in vivo assays. CCK-8, EdU incorporation, and soft agar colony formation assays were performed to examine the effect of GSK-J4 on cell proliferation. Flow cytometry was used to evaluate the effect of GSK-J4 on the cell cycle and apoptosis. RNA-seq and Western blotting were conducted to explore the molecular mechanisms of GSK-J4. An orthotopic xenograft model was established to determine the effect of GSK-J4 on tumor growth.

Results

GSK-J4 significantly inhibited retinoblastoma cell proliferation both in vitro and in vivo, arrested the cell cycle at G2/M phase, and induced apoptosis. Mechanistically, GSK-J4 may suppress retinoblastoma cell growth by regulating the PI3K/AKT/NF-κB signaling pathway.

Conclusions

The antitumor effects of GSK-J4 were noticeable in retinoblastoma and were at least partially mediated by PI3K/AKT/NF-κB pathway suppression. Our study provides a novel strategy for the treatment of retinoblastoma.

Identifying Treatment Resistance Related Pathways by Analyzing Serum Extracellular Vesicles of Patients With Resistant Versus Regressed Retinoblastoma

Purpose

To identify the genes and pathways responsible for treatment resistance (TR) in retinoblastoma (RB) by analyzing serum small extracellular vesicles (sEVs) of patients with TR active RB (TR-RB) and completely regressed RB (CR-RB).

Methods

Serum-derived sEVs were characterized by transmission electron microscopy and nanoparticle tracking analysis. sEV transcriptome profiles of two TR-RB and one CR-RB with good response (>20 years tumor free) were compared to their age-matched controls (n = 3). Gene expression data were analyzed by the R Bioconductor package. The CD9 protein and mRNA expression of CD9, CD63, and CD81 were studied in five RB tumors and two control retinae by immunohistochemistry and quantitative reverse transcription-polymerase chain reaction.

Results

The isolated serum sEVs were round shaped and within the expected size (30-150 nm), and they had zeta potentials ranging from -10.8 to 15.9 mV. The mean ± SD concentrations of sEVs for two adults and four children were 1.1 × 1012 ± 0.1 and 5.8 × 1011 ± 1.7 particles/mL. Based on log2 fold change of ±2 and P < 0.05 criteria, there were 492 dysregulated genes in TR-RB and 184 in CR-RB. KAT2B, VWA1, CX3CL1, MLYCD, NR2F2, USP46-AS1, miR6724-4, and LINC01257 genes were specifically dysregulated in TR-RB. Negative regulation of apoptotic signaling, cell growth, and proton transport genes were greater than fivefold expressed only in TR-RB. CD9, CD63, and CD81 mRNA levels were high in RB tumors versus control retina, with increased and variable CD9 immunoreactivity in the invasive areas of the tumor.

Conclusions

Serum sEVs could serve as a potential liquid biopsy source for understanding TR mechanisms in RB.

Salvage Intra-arterial Chemotherapy for Recurrent or Persistent Intraocular Retinoblastoma: A Study of 24 Eyes

OBJECTIVE

To analyze the outcomes of salvage intra-arterial chemotherapy (IAC) for recurrent or persistent intraocular retinoblastoma after failure with other treatment modalities.

DESIGN

Retrospective study.

SUBJECTS

Twenty-four eyes of 23 patients.

INTERVENTION

Intra-arterial chemotherapy.

MAIN OUTCOME MEASURES

Globe salvage, metastasis, and death.

RESULTS

The mean age at the time of salvage IAC was 41 months (median, 36 months; range, 14-86 months). All patients (n = 23) received IV chemotherapy (IVC) as the primary treatment. The mean number of IVC cycles before salvage IAC was 10 (median, 12; range, 6-18). The indications for salvage IAC were tumor recurrence (n = 17; 71%) or persistent tumor (n = 7; 29%) post-IVC. The mean number of salvage IAC cycles was 3 (median, 3; range, 1-6). Of 24 eyes, 17 eyes (71%) achieved tumor regression with salvage IAC, whereas 7 (29%) eyes displayed poor response. Of these 17 eyes with initial tumor regression, 9 (38%) eyes sustained good response, whereas 8 (33%) eyes displayed tumor recurrence over a mean follow-up period of 21 months (median, 21 months; range, 6-44 months). The mean interval between IAC and tumor recurrence (n = 8) was 4 months (median, 3 months; range, 1-14 months). Of these 8 eyes, globe salvage was achieved in 5 (21%) eyes with additional alternate treatment. Of the 7 eyes with poor response to IAC, globe salvage was achieved in 1 (4%) eye with additional alternate treatment. Overall, globe salvage was achieved in 15 (63%) eyes.

CONCLUSIONS

Salvage IAC is an effective treatment for recurrent and persistent retinoblastoma, enabling globe salvage in 63% cases.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any materials discussed in this article.

The role of m6A modification in pediatric cancer

With the development of RNA modification research, the importance of N6-methyladenosine (m6A) in tumors cannot be ignored. m6A promotes the self-renewal of tumor stem cells and the proliferation of tumor cells. It affects post-transcriptional gene expression through epigenetic mechanisms, combining various factors to determine proteins' fate and altering the biological function. This modification process runs through the entire tumors, and genes affected by m6A modification may be the critical targets for cancers breakthroughs. Though generally less dangerous than adult cancer, pediatric cancer accounts for a significant proportion of child deaths. What is more alarming is that the occurrences of adult tumors are highly associated with the poor prognoses of pediatric tumors. Therefore, it is necessary to pay attention to the importance of pediatric cancer and discover new therapeutic targets, which will help improve the therapeutic effect and prognoses of the diseases. We collected and investigated m6A modification in pediatric cancers based on mRNA and non-coding RNA, finding that m6A factors were involved in glioma, hepatoblastoma, nephroblastoma, neuroblastoma, osteosarcoma, medulloblastoma, retinoblastoma, and acute lymphoblastic leukemia. Consequently, we summarized the relationships between the m6A factors and these pediatric cancers.

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.

High-risk features in primary versus secondary enucleated globes with advanced retinoblastoma: a retrospective histopathological study

PURPOSE

The management of bilateral advanced retinoblastoma (RB) cases is challenging with attempts to use neoadjuvant therapy salvaging of one of the globes. Our aim in this study was to demonstrate the effect of this primary therapy on the histopathological features and risk factors in secondary enucleated compared to primarily enucleated globes with groups D and E RB.

METHODS

We retrospectively reviewed all enucleated globes with advanced RB received in the pathology laboratories over a period of 5 years. Patients were divided into two groups: one with primary enucleations and another with at least one secondary enucleated globe, and their demographic and clinical data were analyzed. The enucleated globes in the two groups were analyzed to compare the general histopathological features including tumor seeding, size, differentiation, growth pattern, mitotic figures, and focality. More importantly, high-risk features: choroidal invasion, optic nerve (ON) invasion, iris/anterior chamber invasion, ciliary body invasion, and scleral and extra-scleral extension, as well as the pathological classification of the tumor (pT) according to the American Joint Committee on Cancer 7th edition were also compared between the two groups.

RESULTS

We had a total of 106 enucleated globes (78 primary and 28 secondary enucleations) from 99 patients with advanced RB (73 patients with primarily and 26 with secondarily enucleated globes). Demographic and clinical profiles of patients were similar in both, but the mean interval from presentation to enucleation was significantly longer in the secondary enucleations (P = 0.015). Rare/occasional mitotic figures were observed in secondary enucleations using multivariate analysis (P = 0.003). Primarily enucleated globes had higher risk of tumor seeding (P = 0.020), post-laminar/surgical margin ON invasion (P = 0.001), and massive choroidal invasion (P = 0.028). Half of the secondary enucleated globes had tumors confined to the globes without invasion (pT1) and statistically significant lower tumor classifications (pT1 or pT2a) compared to primary enucleations (P =0.001). However, 18% of the secondarily enucleated globes in 3 patients had unfavorable outcome with RB-related mortality after a period of 1-4 years.

CONCLUSIONS

Secondary enucleated globes with advanced RB show favorable histopathological findings mainly less mitosis. These eyes have significantly lower chance for harboring choroidal and ON invasion, thus mostly classified as pT1 or pT2a when compared to primarily enucleated globes. The decision for secondary enucleation was observed to be significantly delayed (8.0 months ± 9.8). Prompt decision for needed enucleation based on the response to primary treatment and careful histopathological examination of enucleated globes are essential to prevent disease-related mortality.

Epidemiological profile of retinoblastoma in North India: Implications for primary care and family physicians

Background:

Retinoblastoma is the most common primary intraocular malignancy among children. Despite being curable in early stages, majority of the cases in India present in late stages, when outcomes are very poor.

Objectives:

The aim of this study was to assess the epidemiological profile, clinical characteristics, and treatment practices among retinoblastoma patients in north India.

Materials and Methods:

Data on all patients with retinoblastoma, over a 10-year-time period from 2009 to 2018, who were treated in a tertiary care hospital in north India, were assessed. Data were analyzed to describe the demographic characteristics, clinical features in terms of stage at presentation, and management practices in terms of diagnostic investigations and treatment. The statistical significance for difference in percentages was assessed using Fischer's exact test at a 5% significance level.

Results:

A total of 25 retinoblastoma patients were enlisted, of whom one was excluded as it was adult onset retinoblastoma. The median age at presentation was 3 years, with a male to female ratio of 1:1.4. Bilateral presentation was seen in 16.6% cases. Majority (66.6%) of the patients underwent magnetic resonance imaging of brain and orbit as a part of the diagnostic workup. Intraocular disease was seen in 58.3% patients, whereas 41.6% patients had extraocular disease. Local therapy with vision preservation could be used only in 8.3% patients, whereas 87.5% patients were referred for enucleation. Chemotherapy with combination of vincristine, etoposide, and carboplatin was used extensively both, in neoadjuvant setting (83.3%) and in the adjuvant setting.

Conclusion:

Despite availability of treatment for eye preservation, its utility is limited due to the advanced stage at presentation. Awareness about the disease and its symptoms for early diagnosis, especially with the Mid-Level Health Provider at Health and Wellness Centers, is likely to improve early reporting and treatment and meeting the Vision 2020 goals.

Enucleated globes with advanced retinoblastoma: correlation of histopathological features and reclassification of tumors according to the 8th edition of the American Joint Committee on Cancer (AJCC)

PURPOSE

We aim to study certain histopathological characteristics of the retinoblastoma (RB) tumors in globes with clinically advanced RB, which can be correlated with the high-risk features including: tumor differentiation, growth pattern and focality. We also aim to reclassify the tumor pathologically in the analyzed cases according to the American Joint Committee on Cancer (AJCC) 8th edition in an attempt to compare the validity of this newest classification.

METHODS

Retrospective study of patients diagnosed with clinical RB of groups D and E during the period: January 2013 to December 2017 at King Khaled Eye Specialist Hospital (KKESH) and King Abdulaziz University Hospital (KAUH). Charts were reviewed for demographic and basic clinical data. Histopathological features (tumor differentiation, growth pattern, focality, seeding, and presence of choroidal invasion (focal versus massive), level of optic nerve (ON) invasion, anterior chamber invasion, scleral and extra-scleral extension, and finally the documented pathological tumors (pT) classification based on the AJCC 7th edition were collected.

RESULTS

We included 146 eyes with advanced retinoblastoma (groups D and E) from 104 patients. Gender distribution was almost equal with 54 males. Median age was 12 months (range 1-96 months), and a mean age was 17.1 ± 15.1 months. No family history was found in the majority (94.2%). Clinically, the most common presenting symptoms: leukocoria (73.3%), squint (33.6%) and least commonly proptosis (2.7%). A total of 106 enucleation specimens were reviewed. Degree of RB differentiation was: well differentiated (18%), moderate (30%), poor (35%), and undifferentiated (17%). The most common high-risk features were ON invasion (68%) with the majority being prelaminar in nature, choroidal invasion (45%) with more than half being massive, iris/trabecular meshwork (TM)/Schlemm's canal invasion (8.5%), and then intra-scleral/extra-scleral extension (5%). Less tumor differentiation doubles the relative risk of massive choroidal invasion (with 95% CI) with a statistically significant P value (P = 0.030). Endophytic RB was associated with vitreous seeding, while exophytic tumors were associated with subretinal seeding (P = 0.001) each. Ten cases with combined ON invasion (pre-laminar) and focal choroidal invasion were reclassified pT2a in the AJCC 8th edition instead of pT2b in the older 7th edition.

CONCLUSIONS

Our demographic and basic clinical data for advanced RB are comparable to other similar reports. The tumor growth pattern correlates well with the type of seeding observed in enucleated globes with RB. Less tumor differentiation is a relative risk of massive choroidal invasion. It is advocated to implement the AJCC 8th edition by ocular pathologists worldwide aiming to histopathologically classify the RB tumor in cases for selective adjuvant chemotherapy.