Benefts forImpact on children with familial retinoblastoma of early delivery

after prenatal RB1 mutation identification

Sameh E. Soliman, MD; Helen Dimaras, PhD; Vikas Khetan, MB, BS; Elise Héon, MD, FRCSC;

Helen S. L. Chan, MB, BS, FRCSC; Brenda L. Gallie, MD, FRCSC

This work was partly presented as an oral presentation by Sameh Soliman in the Research Day

of the Department of Ophthalmology and Visual Sciences of the University of Toronto in

Toronto, 29 May 2015.

Corresponding Author: Dr Brenda Gallie at the Department of Ophthalmology and Vision

Sciences, the Hospital for Sick Children, 525 University Avenue, 8th floor, Toronto, ON M5G 2L3,

Canada, or at brenda@gallie.ca

Authors’ Affiliations:

Departments of Ophthalmology & Vision Sciences, (Soliman, Dimaras, Héon , Gallie) and

Division of Hematology/Oncology, Pediatrics (Chan), Hospital for Sick Children, Toronto,

Canada; Division of Visual Sciences, Toronto Western Research Institute, Toronto, Canada

(Dimaras, Héon , Gallie); Ophthalmology Department, Faculty of Medicine, Alexandria

University, Egypt (Soliman); Sankara Nethralya Hospital, Chennai, India (Khetan); Departments

of Pediatrics (Chan), Molecular Genetics and Medical Biophysics (Gallie) and Ophthalmology

(Dimaras, Héon, Gallie), University of Toronto, Toronto, Ontario, Canada.

Author contributions:

Drs. Soliman and Gallie had full access to all the data in the study and take responsibility for the

integrity of the data and the accuracy of the data analysis.

Study concept and design: Soliman, Dimaras, Gallie, Khetan

Acquisition, analysis, or interpretation of data: Soliman, Dimaras, Khetan, Gallie

Drafting of the manuscript: Soliman, Dimaras, Khetan, Gallie

Critical revision of the manuscript for important intellectual content: Dimaras, Gallie, Chan,

Héon

Statistical analysis: Soliman, Dimaras, Gallie

Study supervision: Chan, Héon, Gallie

Financial Support: None

Conflict of Interest: No conflicting relationship exists for any author

Running head: Early delivery of familial retinoblastoma

Address for reprints: Dr. Brenda Gallie at the Department of Ophthalmology and Vision

Sciences, the Hospital for Sick Children, 525 University Avenue, 8th floor, Toronto, ON M5G 2L3,

Canada

Word count: 3359 /3000 words

Numbers of figures and tables: 3 figures and 2 tables

Key Words: prenatal retinoblastoma, retinoblastoma gene mutation, RB1, molecular testing,

late pre-term delivery, near-term delivery, amniocentesis

Abstract (416 /350)

IMPORTANCE Prenatal RB1 Mutation detection enables prediction of familial retinoblastoma. Early

delivery to allow treatment of smaller tumors may minimize invasive therapy and achieve better overall

treatment outcome.

OBJECTIVE To compare overall outcomes and treatment intensity of infants with familial retinoblastoma

diagnosed prenatally to carry an RB1 mutation and delivered early term or late preterm, compared to

infants diagnosed postnatally.

DESIGN A retrospective, observational study of children born between 1 June 1996 and 1 June 2014

with familial retinoblastoma cared for at Hospital for Sick Children, followed till April 2015.

SETTING This study was conducted at the academic institutional retinoblastoma referral center.

PARTICIPANTS: All children with familial retinoblastoma treated at SickKids were included. All children

remain under care at the Hospital for Sick Children.

EXPOSURE(S) Infants shown on amniocentesis to carry the parent’s RB1 mutant allele were planned for

early term or late preterm delivery (36-37 weeks of gestation), compared to normal term delivery (40

weeks of gestation) and postnatal RB1 testing. All children received treatments for eye tumors.

MAIN OUTCOME MEASURES The hypothesis prior to data collection was that preterm delivery of

infants at near 100% risk of bilateral retinoblastoma safely optimizes visual outcome and minimizes use

of invasive treatments. Primary study outcome measurements were gestational age, age at first tumor,

eye classification and staging, treatments given, visual outcome, number of anesthetics, pregnancy or

delivery complications, and estimated overall cost of caretreatment burden.

RESULTS Of 21 infants shown to carry their parent’s RB1 mutation, 12 had been tested prenatally and 9

after birth. Of the infants tested prenatally, 9 were induced at 36-38 weeks gestation because of risk for

retinoblastoma and 3 were born spontaneously preterm. Immediate postnatal examination revealed

vision-threatening tumors in 25% (3/12) of infants diagnosed prenatal to carry the family’s RB1

mutation, compared to 67% (6/9) of those diagnosed postnatal. All patients eventually developed

tumors in both eyes. Good vision was maintained in all patients diagnosed prenatal; treatments included

focal therapy (all), later systemic chemotherapy (5), enucleation and stereotactic radiation (1). Full-term

infants received focal therapy (all), systemic chemotherapy (4), stereotactic radiation (2), and

enucleation of one eye (4), with worse visual outcome. One child in the postnatal RB1 mutation

detection developed extraocular diseasehad high risk histopathologic features and still under active

treatment.

CONCLUSIONS AND RELEVANCE: Prenatal diagnosis of retinoblastoma followed by late preterm and

near-term delivery had shown a decrease in eyes with tumor at birth and a better visual outcome when

compared to those with full term delivery with no complications related to preterm delivery. Prenatal

diagnosis helps anticipation and proper planning of management with respect to both the child and the

family.

Introduction

Retinoblastoma, the most common primary ocular malignancy in children, is initiated when both alleles

of the RB1 tumor suppressor gene are inactivated in a precursor retinal cell, and progresses when

mutations in other specific genes occur.1,2 Both alleles may be lost only in the somatic cell from which the

tumor arises, however, in about 50% of children, a germline mutation predisposes to the development of

multiple retinal tumors during childhood, and other cancers later in life. Ten percent of patients display a

family history of disease, inheriting a family-specific mutation from a parent.1,3

Children with RB1 germline alleles may already have retinoblastoma tumor(s) at birth, which are

often in the posterior pole of the eye where they threaten vision.4-8 Preservation of vision with treatment of

these small tumors is often difficult, because focal treatment in proximity to the optic nerve and macula

may compromise vision. Most of these children are bilaterally affected, with either simultaneous or

sequential detection of tumors.4,7 Later developing tumors tend to be located peripherally.7,9 Low

penetrance mutations (10% of families)3 and mosiacism result in fewer tumors and more unilaterally

affected children.10 The timing of first tumors after birth has not been studied.

It is recommended that infants with a family history of retinoblastoma be screened as soon as

possible after birth and repeatedly for the first few years of life, including under anaesthesia, aiming at

early diagnosis when tumors are small and treatable with less invasive therapies for salvage of the eye and

vision.6,7,11

Full term birth is generally defined as live birth occurring between 38 and 40 weeks gestation.

Preterm birth is defined as live birth occurring before completion of 37 weeks gestation. Infants born after

completion of 37 and before 39 weeks gestation are considered early term.12,13 The main concern with late

preterm or early term delivery is its reported effect on neurological and cognitive development and later

school performance of children with a wide range of indications for early delivery,14-16 but visual

dysfunction from a large macular tumor may risk similar neurocognitive defects due to blindness17,

although this has not been studied.

We now present the first report of outcomes of prenatal genetic screening and late preterm or early

term delivery for treatment of retinoblastoma for children demonstrated to carry the RB1 mutant allele of

a parent. We show that prenatal molecular diagnosis and preterm delivery for children carrying a

germline RB1 mutant allele resulted in early detection and treatment of small tumors, lower treatment

morbidity, better tumor control, and visual outcome, compared to children born full term at 39-40 weeks.

Methods

Study Design

Research ethics board approval (REB approval number 1000028725) was obtained from The Hospital

for Sick Children (SickKids) for a retrospective review of medical records of all children with familial

retinoblastoma seen at SickKids, and born between 1 June 1996 and 1 June 2014. Data collected

included: relation to proband; laterality of retinoblastoma in proband; sex; gestational age at birth;

pregnancy, prenatal abdominal ultrasound if done; delivery or perinatal complications; type of genetic

sample tested and result; penetrance of RB1 mutaion; age and location of first and all subsequent tumor

(s) in each eye; treatments used; number of anaesthetics; International Intraocular Retinoblastoma

Classification18 of each eye (IIRC); Tumor Node Metastasis (TNM) staging for eyes and child11; treatment

duration; date of last follow-up; and visual outcome at last follow-up in Snellen and LogMAR

decimalvalues. RB1 mutation testing was performed by Retinoblastoma Solutions before 2013, and

Impact Genetics after 2013, as previously described.19

The gestational age at birth for each child was calculated (taking 39 weeks as full term). Vision

threatening tumors were defined as close to optic nerve or macular (IIRC18 Group B or worse).

Treatments were summarized as focal therapies (Laser therapy, cryotherapy and periocular subtenon’s

injection of chemotherapy) or systemic therapies (systemic chemotherapy or stereotactic external beam

irradiation). Treatment burden (defined by the impact of treatmnet course on general health and

development of the child and potential impact on the his family) was evaluated based on i) duration of

active treatment (time from diagnosis to last treatment), ii) use of systemic chemotherapy or radiation, iii)

number of examinations under anesthesia (EUAs), and iv) occurrence of extraocular disease (Figure 1).

Treatment success was defined as avoidance of enucleation or external beam irradiation or extraocular

disease. Acceptable visual outcome was defined as visual acuity > better than 20/200 (>0.1 in 1-LogMAR

scale or <1 in LogMARdecimal scale) (cut edge of legal blindness). A legally blind child is defined as

best eye visual acuity < better than 20/200 (0.1 in decimal<0 in 1-LogMAR scale).

Statistics

Basic descriptive statistics (student t-test, chi square test (when all cell frequencies are more than 5),

Fisher exact test (when any cell frequency is less than 5), Mann Whitney test and Mood’s median test)

were used for statistical comparisons between patients who underwent prenatal testing and preterm

delivery (Cohort 1) and those who were diagnosed postnatal (Cohort 2). Correlations and Kaplan-Meyer

survival graphs were plotted using Microsoft Excel 2007.

Results

Patient Demographics

Twenty-one children with familial retinoblastoma were reviewed (11 males, 10 females) were eligible for

this study (Supplementary Table 1). Diagnosis for Cohort 1 (9 children) was by observation of prenatal

retinoblastoma tumor (child #9) or postnatal tumor (child #8) or postnatal testing for the parental RB1

mutation: 6 were delivered full term and 3 late preterm because of pregnancy-induced hypertension (#7),

fetal ultrasound evidence of retinoblastoma20 (#9) or spontaneous delivery (#8). The 12 children (57%)

(Cohort 2) were prenatally diagnosed to carry their family’s RB1 mutation and planned for late preterm or

early term delivery: 3 were spontaneously premature (#10, 13, 15; 28-37 weeks gestation) and 9 were

referred to a high-risk pregnancy unit for elective late preterm or early term delivery (36-38 weeks

gestation).

Molecular diagnosis

All study subjects were offspring of retinoblastoma probands. Nineteen probands were bilaterally,

and 2 were unilaterally affected (mother #8, father #19). The familial RB1 mutations were previously

detected except for the unilaterally affected parent of #8, who had not been tested and understood that her

children had no risk since she was unilaterally affected. Cohort 1 children (#1-9) tested postnatal for their

family’s RB1 mutation by blood; Cohort 2 children (#10-21) were tested prenatal by amniocentesis at 16-

33 weeks gestation.

Null RB1 mutations were present in 16 families; 5 had low penetrance RB1 mutations (whole gene

deletion #19; weak splice site mutations #15, 18, 21; and C712R19). No proband in this study was mosaic

for the RB1 mutation. All study subjects were eventually bilaterally affected. At birth, null RB1 mutations

resulted in no tumors (IIRC18 Group 0) in 7/15 (47%) infants and 17/30 (57%) eyes; and low penetrance

mutations resulted in no tumors in 5/5 (100%) infants and 10/10 (100%) eyes (p=0.04* for patients,

p=0.02* for eyes; Fisher exact test) (Table 1).

The age at first tumor in either eye was significantly younger for those with null mutations (mean

84, median 39 days), than those with low penetrance mutations (mean 135, median 120 days) (P=0.03*,

Phi=0.38, Mood’s median test). However, the gestational age at first tumor for those with null mutations

(mean 71, median 33 days) tended to be younger but was not significantly different, than for those with

low penetrance mutations (mean 111, median 81 days) (P=0.06, Phi=0.32, Mood’s median test). (Child

#8 was excluded from these calculations as the child was first examined at 3 months of age with Group

A/D tumors, so age at first detectable tumor is unknown) (table 1c).

Classification of Eyes at Birth

Thirty-three percent (3/9) of Cohort 1 and 75% (9/12) of Cohort 2 were free of visible tumor in

either eye at birth (Table 1a, Figure 1) (p=0.09). We assumed that child #8 had tumor at birth since he had

a group D IIRC18 eye at 3 months of age. Of eyes, 79% (19/24) of Cohort 1 eyes were tumor-free at birth,

compared to 33% (6/18) of Cohort 2 eyes (p=0.026*, Chi Square test), excluding the IIRC18 Group A eye

of child #8, as above (Table 1b).

All patients eventually developed tumors in both eyes regardless of whether their RB1 mutation was

full or low penetrance. Tumors emerged at a younger age in the macular and peri-macular region (IIRC18

Group B), as previously described21. The median gestational age of diagnosis of 14 IIRC18 B eyes (all

threatening optic nerve and fovea, 6 also >3 mm) was 38 days, tended to be younger than of the 103 days

for 26 IIRC18 A eyes (< 3mm and away from optic nerve and fovea) 18(P=0.32, Phi=-0.19, Mood’s median

test).

Bilateral IIRC18 Group A eyes were present at initial diagnosis (optimal situation for achieving good

vision with minimally invasive therapy) in 2/9 (22%) children in Cohort 1 compared to 8/12 (67%) in

Cohort 2 (p=0.009*, Fisher exact test) (Table 2a). IIRC18 Group A was the initial diagnosis of 9/18 (50%)

eyes in Cohort 1, compared to 15/22 (77%) eyes in Cohort 2 (p=0.33, Table 2a). One eye was an IIRC18 D

eye and presented at age of 3 months (child#8).

Treatment Course

All infants were frequently examined from birth onwards (except child #8 who presented at age 3

months) as per the National Retinoblastoma Strategy Guidelines for Care.11 If there were no tumors at

birth, each child was examined awake every week for 1 month, every 2 weeks for 2 months. After 3

months of age, the children had an examination under general anesthesia (EUA) every 2-4 weeks. If there

was tumor at birth, the children had EUAs every 2-4 weeks until control of tumors. Cohort 1 patients

were treated with focal therapy (all), chemotherapy (4), stereotactic radiation (2), and enucleation of one

eye (5) (Supplementary Table 1, Figures 1). Cohort 2 patients were treated with focal therapy (all); later

systemic chemotherapy using vincristine, carboplatin, etoposide and cyclosporine (Toronto protocol)(5),

enucleation of one eye and stereotactic radiation (1) (Figure 1).

Treatment burden showed no statistical significant difference between Cohort 1 and 2 in any of the

four parameters tested. The median active treatment duration was 458 days (0-2101 days) in Cohort 1,

compared to 447 days (0-971 days) in Cohort 2 (p=1, Mood’s median test). Treatment by focal therapy

alone (avoidance of systemic chemotherapy or EBRT) was possible in 4/9 (44%) of Cohort 1 and 7/12

(58%) of Cohort 2 (P=0.67, Fisher exact test) (Table 2b). The median number of EUAs in cohort 1 is 25

(range 18-81) and for cohort 2 is 29 (range 20-41) EUAs (p=1, Mood’s median test). One child (11%)

from Cohort 1 developed extraocular orbitalhigh risk disease disease and still under active treatment

(P=0.4, Fisher exact test) (table 2b).

Outcomes

There were no adverse effects associated with induced or natural preterm or early term birth, and no

pregnancy, delivery or perinatal complications reported for any of the infants. Follow up (mean, median)

was overall 8, 5.6 years; Cohort 1, 8.4, 5.6 years; and Cohort 2, 7.6, 5.8 years (Supplementary Table 1).

Neither enucleation nor external beam irradiation were required (defined as treatment success) in

44% of Cohort 1 and 92% of Cohort 2 (P=0.046*, Fisher exact test). Kaplan Meier ocular survival for

Cohort 1 was 62% compared to 92% for Cohort 2 (Figure 2). All children from both Cohorts are still

alive; one child from Cohort 1 is still under active treatment.

Visual outcomes were acceptable for 50% of eyes in Cohort 1 and 92% of eyes in Cohort 2

(P=0.014*, Fisher exact test). Children were legally blind (visual acuity less than 20/200 using both eyes)

in 22% of Cohort 1 and 0% of Cohort 2 (p=0.017*, Fisher exact test). Seventy one percent of eyes (17/24)

of cohort 2 had final visual acuity better than 20/40 compared to 50% (9/18) of eyes in cohort one.

Treatment success (avoidance of enucleation and/or stereotactic radiation) and good vision per eye

was documented 50% (9/18) of Cohort 1 and 88% (21/24) of Cohort 2 (p=0.014*, Fisher exact test)

(Table 2b, Figure 1). A negative correlation was found between gestational age and final visual outcome

(r=-0.03) with better visual outcome in earlier deliveries (Figure 3).

Discussion

In the first study of its kind, we report that prenatal molecular diagnosis of familial retinoblastoma and

elective late-preterm or early term delivery allowed monitoring for, and treatment of, tumors as they

emerged, which resulted in better ocular and visual outcomes and less severe medical interventions in

very young children. This data illustrates that for infants with close to 100% risk of retinoblastoma in

both eyes because they carry an RB1 mutant allele, the risk of vision and eye loss despite intensive

therapies, outweighs the risks associated with induced late preterm delivery (Figure 1). Consistent with

previous reports,5 67% of children with a germline gene mutation already had tumors at full term birth.

Reduction to 25% when the germline mutation was prenatally detected and earlier delivery (late preterm

or early term) was accomplished.

It is practical to identify 96% of the germline mutations in bilaterally affected probands and to

identify the >15% of unilateral probands who carry a germline gene mutation.3,10,22 When the family's

unique mutation is identified in the proband, molecular testing of family members can determine who else

carries the mutation and is at risk to develop retinoblastoma. We report on 12 infants identified by in

utero molecular testing to carry the mutant RB1 allele of a parent. The 50% of tested infants who did not

inherit their family’s mutation require no surveillance, can be born at full term and do not need

examinations to detect tumors, since they are at no greater risk of developing retinoblastoma than the

general population.

Without molecular information, repeated retinal examination is recommended for all first degree

relatives until age 7 years, the first 3 years under general anesthesia.11 Multiple studies now suggest

deleterious effects of multiple general anesthetics in early infancy on the neurocognitive development of

the child.23-25 Such repeated clinical screening also imposes psychological and financial burden on the

children and families. Identification by early molecular RB1 testing of the children who are not at risk

and require no clinical intervention cost significantly less than direct costs than clinical screening for

tumors.19,26

Optimal treatment for retinoblastoma includes combined therapeutic modalities to optimize vision

and minimize treatment morbidity, while achieving tumor control. However, retinoblastoma treatment in

the first 3 months of life is a challenge since these young children may not have sufficient renal function

for full dose systemic therapies. In our study child #9, who had a tumor at 36 weeks gestation large

enough for detection by obstetrical ultrasound, showed drug-resistant tumor following reduced-dose

chemotherapy, ultimately requiring enucleation of one eye.20 Good treatment options at this age are

limited to focal therapy (laser and cryotherapy) and periocular chemotherapy.27

The earliest tumors commonly involve the macular or paramacular region, threatening loss of central

vision, while tumors that develop later are usually peripheral, where they have less visual impact.5,27-30 In

our cohort, the risk of having a vision threatening tumor dropped from 39% to 17% by prenatal mutation

detection and planned earlier delivery. Macular and paramacular tumors are difficult to manage by laser

therapy or application of a radioactive plaque, since these threaten the optic nerve and central vision.

Systemic chemotherapy effectively shrinks tumors such that focal therapy can be applied with minimal

visual damage. Systemic chemotherapy in neonates is difficult due to the unknowns of immature liver and

kidney function to metabolize the drugs increasing the potential of severe adverse effects. The

conventional recommendation is to either reduce chemotherapy dosages by 50%, particularly for infants

in the first three months of life,31 or administer a single agent carboplatin chemotherapy 27; but the partial

doses set up for development of multidrug resistance proteins in the tumor cells that promote

chemotherapeutic drug efflux from tumor cells preventing drug accumulation in tumor cells, making later

recurrences difficult to treat. 32-34 Periocular topotecan for treatment of small-volume retinoblastoma 35

may increase the effectiveness of focal therapy.

Imhof et al 7 in the Netherlands screened 135 children at risk of familial retinoblastoma 1-2 weeks

after birth without molecular diagnosis and discovered 17 cases of familial retinoblastoma (13% of

screened children at risk). 70% of them had RB in at least one eye at first examination and 41% of eyes

had vision threatening tumor to the macula. 41% (7/17) of patients had failure of treatment (EBRT or

enucleation) and one case of metastasis. 73.5% of eyes (27/34) had good visual acuity (defined by vision

>20/100) that will reduce to 56% (19/27) if we consider eyes with EBRT as failure. These results

correspond to our postnatal screening cohort showing similar results. On the contrary, the prenatal

diagnosis and planned earlier delivery cohort showed less vision threatening tumors (17%), less treatment

failure (8%) and better visual outcome (88%).

Early screening of at risk infants with positive family history as soon an possible after birth is the

internationally accepted model (whether intensive screening is utilized or not).7,36 Here we propose the

prenatal screening of the known mutation in the probands by amniocentesis in the second half of

pregnancy where the risks of miscarriage are minimal (0.1-1.4%).37,38 For those who are confirmed to

have the mutation; planned late preterm or early term delivery at 36-38 weeks of gestation and as a result

a smaller tumor with less macular involvement leading to better visual outcome is anticipated. there was

no difference between the two Cohorts in the treatment burden and the systemic chemotherapy usage as

we didn't change the treatment course by early delivery but changed the treatment outcome by catching

the tumors at earlier stage also multiple focal treatments in both Cohorts were for small new tumors that

occurred due to the nature of the germline tumor and not related to early delivery or prenatal detection.

The main concern with late preterm or early term delivery is its reported effect on neurological and

cognitive development and later school performance,14-16 but visual dysfunction from a larger macular

tumor can cause similar neurocognitive defects due to blindness17 despite never studied in a comparative

manner. So, earlier delivery must be discussed thoroughly through the team of neonatologist

ophthalmologist and oncologist to reach the best timing for better outcome 39 so rather than focusing on

the combination of treatments to tackle burdensome disease, we showed safe preterm delivery resulted in

a decreased tumor burden at birth that was significantly easier to treat (Figure 2, Table 2). Safe preterm

delivery resulted in more infants born tumor-free, facilitating frequent surveillance to detect tumors as

they emerged, and focal therapy of smaller, easier to control masses, causing minimal damage to vision

(Figure 1,2).

Counseling on reproductive risks is imperative for families affected by retinoblastoma even in

unilateral probands. In developed countries; where current therapies result in extremely low mortality,

most retinoblastoma patients will survive to have children. Prenatal diagnosis in the published literature

has been cited as useful in preimplantation genetics (to ensure an unaffected child) or to inform parents

who wish to terminate an affected pregnancy.40 There have been two prior reports indicating pre-natal

molecular testing for retinoblastoma; in one, the fetus sibling of a proband was found not to carry the

sibling’s mutation 41, and in the other, 3 of 5 tested fetuses of a proband were terminated once molecular

testing confirmed the mutation in the offspring.42 We are first to report that elective safe late-preterm

delivery of prenatally diagnosed infants with retinoblastoma results in improved outcomes. It is our

experience that for retinoblastoma survivors and their relatives who understand fully the underlying risks,

they are more interested in early diagnosis to optimize options for therapy in affected babies rather than to

consider termination of pregnancy. We also surmise that since germline mutations predispose to future,

second cancers in affected individuals, perhaps it is worth investigating the role of cord blood banking

infants that are prenatally molecularly diagnosed with retinoblastoma. A long-term study could show the

impact of such an approach to patient outcomes in their adulthood. We conclude that since infants with

familial retinoblastoma are likely to develop vision-threatening macular tumors, prenatal molecular

diagnosis and safe, late-preterm delivery will increase the chance of good visual outcome with decreased

treatment associated morbidity.

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Table 1: Occurrence of tumors at birth according to the type of RB1 mutation (Null vs Low penetrance

mutation) in the whole child (table 1a), eyes (table 1b) and prevalence of bilateral IIRC group A tumors

(table 1c).

Table 1a Table 1b Table 1cChildren with tumors at

birth Eyes with tumors at birth Children with A/A eyes at first tumors

(child #8 included) (excluding IIRC A eye of

child #8 first examined at age 3 months)

(child #8 included)

YES

NO total

% NO

YES

NO total

% NO

YES

NO total % NO

Null RB1 mutation 9 7 16 44% 14 17 31 55% 6 9 15 60%Cohort 1 5 2 7 9 6 15 1 6 7Cohort 2 3 5 8 5 11 16 5 3 8

Low penetrance RB1 mutation 0 5 5 100

% 0 10 10 100% 3 2 5 40%

Cohort 1 0 1 1 0 2 2 0 1 1Cohort 2 0 4 4 0 8 8 3 1 4

Total 21 41 21 FET p=0.04* p=0.02* p=0.61

Table 2: Outcome parameters for both groups per eye (table 2a) and per child (table 2b) and their level of

significance.

Table 2a: Outcome parameters per eye

Postnatal RB1 test (n=18)

Prenatal RB1 test (n=24) P

value No % No %

Tumor(s) at birth 10 0.56 5 21% 0.027*Treatment success 11 0.61 22 92% 0.025*

Ocular salvage 13 0.72 23 96% 0.07Visual Outcome 0.014*

Acceptable vision 9 50% 21 88% Poor Vision 9 50% 3 12%

Table 2b: Outcome parameters per child

Postnatal RB1 test (n=9)

Prenatal RB1 test (n=12) P

value No % No %

Tumor(s) at birth 6 67% 3 25% 0.087IIRC AA at first tumor 1 11% 8 67% 0.009*

Treatment burden 0.67Focal therapy only 4 44% 7 58%  

Systemic chemotherapy 5 56% 5 42%  Treatment success 3 33% 11 92% 0.002*

Ocular salvage 4 44% 11 92% 0.046*High risk disease 1 11% 0 0% 0.4Visual Outcome 0.017*

Acceptable vision 7 78% 12 100%  Blind 2 22% 0 0%  

Figure 1: Schematic representation of each child in Cohort 1 (postnatal RB1 detection) and Cohort 2

(prenatal RB1 detection) from delivery until time of first tumor, IIRC at first tumor per eye, treatment

burden (focal, systemic chemotherapy, or radiation treatment). Number of EUAs, visual acuity at last

follow up and follow up duration.

Gestational Age

20/20; 20/25

28 29 30 31 32 33 34 35 36 37 38 39 40 1 2 3 4 5 6 7 8 9 10

20/20; 20/200

3 20/20; E

1 20/20; 20/20

8

20/20; 20/25

20/30; 20/60

20/600; 20/60

9

10

E; 20/30

4 E(OS) 20/20, E

11

20/15; 20/10

20/50; 20/20

13

20/20; 20/25

15

Post

nata

l RB1

test

Pren

atal

RB1

test

5.6

18

7.1

18

14.8 5.2

12.8

9.5

8.8

4.3

6.4

FU (y)

Spontaneous birth Induced birth Birth to first tumor

monthsweeks

E(OS)

20/25; 20/25

17

3.2

6 E; 20/25 2.7

VA (OD, OS)

2 20/200* 3.7

5

IIRC (OD, OS)A, AC, B

A, BA, BA, B

B, A

7 A, B 20/30; 20/30 2.8

(OS)

D, A

B, B

E; 20/20E(OD) 2.4

(OU) E(OD) E; 20/400 15.5

12

14

16

1819

20

21

A, A 15.5

B, AB, B

(OU) E(OD) 4.9B, B

A, A

A, A

A, A

B, B

A, A

20/25; 20/100

B, B 20/125; 20/25

A, A 2.3

EUAs25

41

24

22

21 33

36

30

30

24

31

20

30

43

18

81

41

28

21

23

22 20/20; 20/25 3.8 A, A

E(OD) M

E

Focal Therapy Chemotherapy

Radiotherapy Enucleation

MMetastasis

Figure 2: Kaplan Meyer curves of treatment success showing a significant treatment success in the

prenatal RB1 detection group versus the postnatal RB1 detection group.

Figure 3: A correlation between the Visual acuity at last follow up (1-LogMAR) at Y axis and the

gestational age at delivery in weeks on X.axis showing a negative correlation.

26 28 30 32 34 36 38 400

0.5

1

1.5

2

f(x) = − 0.0284788135593221 x + 1.66274293785311R² = 0.0313248065403924

Gestational age in Weeks

Visu

al A

cuity

in D

ecim

al