Risk of subsequent malignant neoplasms in long-term hereditary retinoblastoma survivors after chemotherapy and radiotherapy

Radiogenomic Predictors of Adverse Effects following Charged Particle Therapy

Radiogenomics is the study of genomic factors that are associated with response to radiation therapy. In recent years, progress has been made toward identifying genetic risk factors linked with late radiation-induced adverse effects. These advances have been underpinned by the establishment of an international Radiogenomics Consortium with collaborative studies that expand cohort sizes to increase statistical power and efforts to improve methodologic approaches for radiogenomic research. Published studies have predominantly reported the results of research involving patients treated with photons using external beam radiation therapy. These studies demonstrate our ability to pool international cohorts to identify common single nucleotide polymorphisms associated with risk for developing normal tissue toxicities. Progress has also been achieved toward the discovery of genetic variants associated with radiation therapy-related subsequent malignancies. With the increasing use of charged particle therapy (CPT), there is a need to establish cohorts for patients treated with these advanced technology forms of radiation therapy and to create biorepositories with linked clinical data. While some genetic variants are likely to impact toxicity and second malignancy risks for both photons and charged particles, it is plausible that others may be specific to the radiation modality due to differences in their biological effects, including the complexity of DNA damage produced. In recognition that the formation of patient cohorts treated with CPT for radiogenomic studies is a high priority, efforts are underway to establish collaborations involving institutions treating cancer patients with protons and/or carbon ions as well as consortia, including the Proton Collaborative Group, the Particle Therapy Cooperative Group, and the Pediatric Proton Consortium Registry. These important radiogenomic CPT initiatives need to be expanded internationally to build on experience gained from the Radiogenomics Consortium and epidemiologists investigating normal tissue toxicities and second cancer risk.

Experimental animal study of docetaxel combined with carboplatin in the treatment of retinoblastoma

The synergistic effects of docetaxel (DTX) combined with carboplatin in the treatment of retinoblastoma (RB) was explored in mouse RB xenografts compared with carboplatin alone and DTX alone groups. Retinoblastoma Y-79 cells (4.0×10⁷/ml) were injected into the vitreous body of the right eye of mice to establish the mouse model of RB xenografts. Then the mice were randomly divided into 4 groups (n=30): DTX combined with carboplatin group (group A), carboplatin group (group B), DTX group (group C) and blank control group (group D). The changes in tumors, the survival time of mice, and the synergistic effects of DTX combined with carboplatin were observed and analyzed. The diameters and weight of the right eyeballs of the Institute for Cancer Research (ICR) mice were significantly larger and higher than those of the left eyeballs in each group, respectively (P<0.05). The diameters and weight in group A were significantly shorter and lighter than those in the other three groups, respectively (P<0.05), and there was no significant difference compared with that of normal eyeballs (P>0.05). There was no difference in diameter and weight between group B and group C (P>0.05), but the diameters and weight were shorter and lighter than those in group D, respectively (P<0.05). The survival time of ICR mice in groups A, B and C was significantly longer than that in group D (P<0.05). The survival time in group A was significantly longer than that in groups B and C (P<0.05). There was no significant difference in the survival time between the group B and group C (P>0.05). DTX, carboplatin and the combination of the two have significant inhibitory effects on RB; however, DTX combined with carboplatin has a better therapeutic effect on RB.

Risk of Soft-Tissue Sarcoma Among 69 460 Five-Year Survivors of Childhood Cancer in Europe

Background

Childhood cancer survivors are at risk of subsequent primary soft-tissue sarcomas (STS), but the risks of specific STS histological subtypes are unknown. We quantified the risk of STS histological subtypes after specific types of childhood cancer.

Methods

We pooled data from 13 European cohorts, yielding a cohort of 69 460 five-year survivors of childhood cancer. Standardized incidence ratios (SIRs) and absolute excess risks (AERs) were calculated.

Results

Overall, 301 STS developed compared with 19 expected (SIR = 15.7, 95% confidence interval [CI] = 14.0 to 17.6). The highest standardized incidence ratios were for malignant peripheral nerve sheath tumors (MPNST; SIR = 40.6, 95% CI = 29.6 to 54.3), leiomyosarcomas (SIR = 29.9, 95% CI = 23.7 to 37.2), and fibromatous neoplasms (SIR = 12.3, 95% CI = 9.3 to 16.0). SIRs for MPNST were highest following central nervous system tumors (SIR = 80.5, 95% CI = 48.4 to 125.7), Hodgkin lymphoma (SIR = 81.3, 95% CI = 35.1 to 160.1), and Wilms tumor (SIR = 76.0, 95% CI = 27.9 to 165.4). Standardized incidence ratios for leiomyosarcoma were highest following retinoblastoma (SIR = 342.9, 95% CI = 245.0 to 466.9) and Wilms tumor (SIR = 74.2, 95% CI = 37.1 to 132.8). AERs for all STS subtypes were generally low at all years from diagnosis (AER < 1 per 10 000 person-years), except for leiomyosarcoma following retinoblastoma, for which the AER reached 52.7 (95% CI = 20.0 to 85.5) per 10 000 person-years among patients who had survived at least 45 years from diagnosis of retinoblastoma.

Conclusions

For the first time, we provide risk estimates of specific STS subtypes following childhood cancers and give evidence that risks of MPNSTs, leiomyosarcomas, and fibromatous neoplasms are particularly increased. While the multiplicative excess risks relative to the general population are substantial, the absolute excess risk of developing any STS subtype is low, except for leiomyosarcoma after retinoblastoma. These results are likely to be informative for both survivors and health care providers.

Retinoblastoma and Neuroblastoma Predisposition and Surveillance

Retinoblastoma (RB) is the most common intraocular malignancy in childhood. Approximately 40% of retinoblastomas are hereditary and due to germline mutations in the RB1 gene. Children with hereditary RB are also at risk for developing a midline intracranial tumor, most commonly pineoblastoma. We recommend intensive ocular screening for patients with germline RB1 mutations for retinoblastoma as well as neuroimaging for pineoblastoma surveillance. There is an approximately 20% risk of developing second primary cancers among individuals with hereditary RB, higher among those who received radiotherapy for their primary RB tumors. However, there is not yet a clear consensus on what, if any, screening protocol would be most appropriate and effective. Neuroblastoma (NB), an embryonal tumor of the sympathetic nervous system, accounts for 15% of pediatric cancer deaths. Prior studies suggest that about 2% of patients with NB have an underlying genetic predisposition that may have contributed to the development of NB. Germline mutations in ALK and PHOX2B account for most familial NB cases. However, other cancer predisposition syndromes, such as Li-Fraumeni syndrome, RASopathies, and others, may be associated with an increased risk for NB. No established protocols for NB surveillance currently exist. Here, we describe consensus recommendations on hereditary RB and NB from the AACR Childhood Cancer Predisposition Workshop. Clin Cancer Res; 23(13); e98-e106. ©2017 AACRSee all articles in the online-only CCR Pediatric Oncology Series.

Retinoblastoma for Pediatric Ophthalmologists

Retinoblastoma can present in 1 or both eyes and is the most common intraocular malignancy in childhood. It is typically initiated by biallelic mutation of the RB1 tumor suppressor gene, leading to malignant transformation of primitive retinal cells. The most common presentation is leukocoria, followed by strabismus. Heritable retinoblastoma accounts for 45% of all cases, with 80% being bilateral. Treatment and prognosis of retinoblastoma is dictated by the disease stage at initial presentation. The 8th Edition American Joint Committee on Cancer (AJCC) TNMH (tumor, node, metastasis, heritable trait) staging system defines evidence-based clinical and pathological staging for overall prognosis for eye(s) and child. Multiple treatment options are available in 2018 for retinoblastoma management with a multidisciplinary team, including pediatric ocular oncology, medical oncology, radiation oncology, genetics, nursing, and social work. Survival exceeds 95% when disease is diagnosed early and treated in centers specializing in retinoblastoma. However, survival rates are less than 50% with extraocular tumor dissemination. We summarize the epidemiology, genetics, prenatal screening, diagnosis, classification, investigations, and current therapeutic options in the management of retinoblastoma.

Sinonasal Leiomyosarcoma: Clinicopathological Analysis of Nine Cases with Emphasis on Common Association with Other Malignancies and Late Distant Metastasis

Sinonasal tract (SNT) leiomyosarcoma (LMS) is exceedingly rare with < 100 cases reported. Their relationship to retinoblastoma and other malignancies, along with previous irradiation has not been clarified. Routine and consultation cases were reviewed for histologically and immunohistochemically proven SNT LMS. The tumors were tested with antibodies against α-smooth muscle actin, desmin, h-caldesmon, HMB45, S100 protein, Rb1, MDM2, CDK4 and EBV (EBER-ISH). Nine tumors affecting 5 males and 4 females aged 26 to 77 years (median: 48 years) were identified in the maxillary sinus (n = 4), nasal cavity (n = 3) and combined SNT (n = 2). Three patients had previous irradiation (2 for retinoblastoma, 1 for fibrous dysplasia) and 1 patient had chemotherapy and stem cell transplantation for Hodgkin lymphoma. One patient had prostatic adenocarcinoma (prior) and rectal adenocarcinoma (post) to the LMS. All patients with follow-up developed either local recurrences and/or metastases, principally to lung (time to metastasis: 16-156 months, mean 62 months). Histologically, 6 tumors were conventional high-grade LMS, two had glycogen-rich clear cell (PEComa-like) morphology and one was spindle cell low-grade. The latter showed grade 2 in the recurrence and grade 3 in the lung metastases. Two cases showed dedifferentiation to anaplastic pleomorphic (inflammatory MFH-like) phenotype. Immunohistochemistry revealed diffuse expression of at least 2 smooth muscle markers in 8 and only actin in one case/s. All other markers were negative. RB1 loss was observed in 6/8 cases tested. Sinonasal tract leiomyosarcomas are rare aggressive sarcomas that frequently develop in a background of previous cancer therapy (4/9), most frequently irradiation. Their varied morphology underlines the wide differential diagnostic considerations. Long-term survival may be achieved with aggressive multimodal therapy.

Germline and somatic genetics of osteosarcoma - connecting aetiology, biology and therapy

Clinical outcomes and treatment modalities for osteosarcoma, the most common primary cancer of bone, have changed very little over the past 30 years. The peak incidence of osteosarcoma occurs during the adolescent growth spurt, which suggests that bone growth and pubertal hormones are important in the aetiology of the disease. Tall stature, high birth weight and certain inherited cancer predisposition syndromes are well-described risk factors for osteosarcoma. Common genetic variants are also associated with osteosarcoma. The somatic genome of osteosarcoma is highly aneuploid, exhibits extensive intratumoural heterogeneity and has a higher mutation rate than most other paediatric cancers. Complex pathways related to bone growth and development and tumorigenesis are also important in osteosarcoma biology. In this Review, we discuss the contributions of germline and somatic genetics, tumour biology and animal models in improving our understanding of osteosarcoma aetiology, and their potential to identify novel therapeutic targets and thus improve the lives of patients with osteosarcoma.

Clinical, epidemiological, and therapeutic profile of patients with a retinoblastoma diagnosis experience in the Costa Rica National Children's Hospital Oncology Unit from January 2009 to December 2015

INTRODUCTION

Retinoblastoma represents only 3% of paediatric cancers, but it is the most prevalent intraocular tumour in this population. It develops in the retina as a primitive neuroectodermal tumour that affects development during gestation. The tumour presents in two different forms depending on whether or not it expresses a genetic modification. For patients diagnosed at preschool age, 75% are unilateral non-hereditary cases. While enucleation is the preferred treatment for advanced stages of the tumour, other modalities, such as systemic and intraocular chemotherapy, radiotherapy and local treatments with thermotherapy, cryotherapy, and brachytherapy can be used to try to preserve the eye. However, applying radiation therapy treatments increases the risk of secondary tumours.

OBJECTIVE

To analyse the results obtained from patients with a retinoblastoma diagnosis at the Costa Rica National Children's Hospital (HNN) Oncology Unit who received external beam radiation therapy and other therapeutic modalities during the period from January 2009 to December 2015.

MATERIALS AND METHODS

Data were extracted from the patient's medical records and entered in a data collection instrument. We then analysed the results and formulated conclusions.

RESULTS

A total of 36 patients were evaluated. This corresponded to 45 cases or the number of eyes affected by bilateral presentation of retinoblastoma. The documented incidence was 0.83 cases per 10,000 live births and the majority were female preschool-age children. Of these, 40% presented bilaterally and 13% were of hereditary origin. Up to 78% of these cases were diagnosed with advanced stage D and stage E. All patients who received conservative treatment progressed, requiring up to four lines of treatment. Eight patients, all in the most advanced stage, received external beam radiation due to the failure of other modalities. The main adverse effects observed were radiodermatitis, facial hypoplasia and conjunctivitis. Additionally, we report the emergence of a secondary neoplasm in two patients, one post-chemotherapy and the other post-radiotherapy.

CONCLUSIONS

Advanced-stage patients who initially received conservative treatments responded more poorly than those treated more aggressively with surgery alone or with surgery combined with another treatment modality. Treatment with radiation therapy was used in 22% of the cases (8 patients) and all patients treated with radiotherapy showed some adverse effects.

Epidemiological trends in 1452 cases of retinoblastoma from the Surveillance, Epidemiology, and End Results (SEER) registry

OBJECTIVE

To assess retinoblastoma epidemiological trends in the Surveillance, Epidemiology, and End Results (SEER) registry.

METHODS

All cases of retinoblastoma in the SEER database from 1973 to 2009 were identified. Kaplan-Meier survival analyses were performed for pathological grade, patient age, sex, year of diagnosis, and treatment modality. Cox proportional hazards regression assessed the impact of patient and tumour characteristics on survival.

RESULTS

1452 cases of retinoblastoma were analyzed. The mean patient age at diagnosis was 1.44 years. The tumour was unilateral in 71.0% and bilateral in 29.0%. The mean follow-up was 129.1 months. Overall survival increased during the study interval. Patients with bilateral tumours were diagnosed at an earlier age (0.46 years) than patients with unilateral disease (1.77 years; p < 0.0001). Bilateral retinoblastoma (90.3% 10-year overall survival) was associated with decreased overall survival than unilateral retinoblastoma (96.1% 10-year overall survival). Bilateral retinoblastoma was also associated with an increased incidence of nonocular malignancies (7.8%) compared with unilateral retinoblastoma (1.3%; p < 0.0001). Grade 1 tumours were diagnosed at a younger age (0.94 years) than grade 3 (2.24 years) and grade 4 tumours (2.14 years; p < 0.0001). Lower grade and lower stage tumours were independently associated with increased survival. In multivariate Cox proportional hazards analysis, T stage and laterality were the only covariates that correlated with overall survival.

CONCLUSIONS

There appear to be associations between retinoblastoma tumour features such as tumour stage, pathological grade, and laterality with patient characteristics such as age at diagnosis, overall survival, and second malignancies.

Second primary malignancies in retinoblastoma patients treated with intra-arterial chemotherapy: the first 10 years

BACKGROUND/AIMS

Survivors of retinoblastoma carry a lifetime risk of secondary malignancies. It is well established that external beam radiation increases this risk; however, the risk with ophthalmic artery chemosurgery (OAC) remains unknown. We report on 10 years of experience with OAC and the rate of second primary malignancy (SPM) development.

METHODS

This is a single-centre retrospective review approved by the Memorial Sloan Kettering Cancer Center Institutional Review Board of all patients who received OAC over a 10-year period, from May 2006 to November 2016. The second tumour incidence and survival in patients with germline disease (bilateral and unilateral with family history or confirmed germline mutation) was estimated using the Kaplan-Meier method. Patients who received external beam radiotherapy were excluded from analyses.

RESULTS

Two hundred and thirty-three patients with heritable retinoblastoma who received OAC were analysed. Nineteen patients were excluded for having received external beam radiation. The Kaplan-Meier estimate of the likelihood for SPM development was 2.7% at 5 years (95% CI 0 to 25). All of the SPMs were pineoblastomas and all patients had bilateral disease in this cohort.

CONCLUSIONS

In our 10-year experience, we have found that SPM development in patients with germline retinoblastoma treated with OAC alone is comparable to previously published rates. In the first 10 years, OAC did not increase the known incidence of SPMs. This cohort will continue to be followed to establish the rate of development with extended follow-up.

A Comprehensive Review of Pediatric Tumors and Associated Cancer Predisposition Syndromes

An understanding of the role of inherited cancer predisposition syndromes in pediatric tumor diagnoses continues to develop as more information is learned through the application of genomic technology. Identifying patients and their relatives at an increased risk for developing cancer is an important step in the care of this patient population. The purpose of this review is to highlight various tumor types that arise in the pediatric population and the cancer predisposition syndromes associated with those tumors. The review serves as a guide for recognizing genes and conditions to consider when a pediatric cancer referral presents to the genetics clinic.

Genetics and Molecular Diagnostics in Retinoblastoma--An Update

Retinoblastoma is the prototype genetic cancer: in one or both eyes of young children, most retinoblastomas are initiated by biallelic mutation of the retinoblastoma tumor suppressor gene, RB1, in a developing retinal cell. All those with bilateral retinoblastoma have heritable cancer, although 95% have not inherited the RB1 mutation. Non-heritable retinoblastoma is always unilateral, with 98% caused by loss of both RB1 alleles from the tumor, whereas 2% have normal RB1 in tumors initiated by amplification of the MYCN oncogene. Good understanding of retinoblastoma genetics supports optimal care for retinoblastoma children and their families. Retinoblastoma is the first cancer to officially acknowledge the seminal role of genetics in cancer, by incorporating "H" into the eighth edition of cancer staging (2017): those who carry the RB1 cancer-predisposing gene are H1; those proven to not carry the familial RB1 mutation are H0; and those at unknown risk are HX. We suggest H0* be used for those with residual <1% risk to carry a RB1 mutation due to undetectable mosaicism. Loss of RB1 from a susceptible developing retinal cell initiates the benign precursor, retinoma. Progressive genomic changes result in retinoblastoma, and cancer progression ensues with increasing genomic disarray. Looking forward, novel therapies are anticipated from studies of retinoblastoma and metastatic tumor cells and the second primary cancers that the carriers of RB1 mutations are at high risk to develop. Here, we summarize the concepts of retinoblastoma genetics for ophthalmologists in a question/answer format to assist in the care of patients and their families.

Ophthalmic artery chemosurgery for eyes with advanced retinoblastoma

BACKGROUND

Surgical removal of one or both eyes has been the most common way to treat children with retinoblastoma worldwide for more than 100 years. Ophthalmic artery chemosurgery (OAC) was introduced 10 years ago and it has been used as an alternative to enucleation for eyes with advanced retinoblastoma. The purpose of this report is to analyze our 9-year experience treating advanced retinoblastoma eyes with OAC.

MATERIALS AND METHODS

Single-arm retrospective study from a single center of 226 eyes with eyes of retinoblastoma patients with advanced intraocular disease defined as both Reese-Ellsworth (RE) "Va" or "Vb" and International Classification Retinoblastoma (ICRb) group "D" or "E" (COG Classification). Ocular survival, patient survival, second cancers, and electroretinography (ERG) were assessed.

RESULTS

Ocular survival at five years for these advanced eyes was 70.2% (95% confidence interval, 57.3%-79.8%). When eyes were divided into groups either by RE classification or ICRb, no significant differences in ocular survival were seen. Ocular survival was significantly better in naïve compared to non-naïve eyes (80.2% vs 58.4%, p = 0.041). The ERG distribution was very similar before and after OAC treatment for the patient population that did not receive intravitreal chemotherapy. Three patients (1.5%) have developed metastatic retinoblastoma (previously reported) and were successfully treated (no deaths).

CONCLUSION

Using OAC for advanced eyes (the majority of such eyes have been enucleated in the past) enables 70% 5-year ocular survival. Treated eyes have a similar ERG distribution before and after treatment. No patient has died of metastatic retinoblastoma.

Incidence of second cancers after radiotherapy and systemic chemotherapy in heritable retinoblastoma survivors: A report from the German reference center

BACKGROUND

Survivors of heritable retinoblastoma carry a high risk to develop second cancers. Eye-preserving radiotherapy raises this risk, while the impact of chemotherapy remains less defined.

PROCEDURE

This population-based study characterizes the impact of all treatment modalities on second cancers incidence and type after retinoblastoma treatment in Germany. Data on second cancer incidence in 648 patients with heritable retinoblastoma treated between 1940 and 2008 at the German national reference center for retinoblastoma were analyzed to identify associations with treatment.

RESULTS

The cumulative incidence ratio (per 1,000 person years) of second cancers was 8.6 (95% confidence interval 7.0-10.4). Second cancer incidence was influenced by type of retinoblastoma treatment but not by the year of diagnosis or by sex. Radiotherapy and systemic chemotherapy increased the incidence of second cancers (by 3.0- and 1.8-fold, respectively). While radiotherapy was specifically associated with second cancers arising within the periorbital region in the previously irradiated field, chemotherapy was the strongest risk factor for second cancers in other localizations. Soft tissue sarcomas and osteosarcomas were the most prevalent second cancers (standardized incidence ratio 179.35 compared to the German population).

CONCLUSIONS

Second cancers remain a major concern in heritable retinoblastoma survivors. Consistent with previous reports, radiotherapy increased second cancer incidence and influenced type and localization. However, chemotherapy was the strongest risk factor for second malignancies outside the periorbital region. Our results provide screening priorities during life-long oncological follow-up based on the curative therapy the patient has received and emphasize the need for less-detrimental therapies for children with heritable retinoblastoma.

Orbital medulloepithelioma in an adult patient: Radiation-induced second neoplasia?

Second cancers in survivors of hereditary retinoblastoma occur much more commonly than in the general population. This can be attributed both to the germline mutation of the RB gene and chemoradiation used for treatment of this paediatric cancer. Medulloepithelioma is an uncommon tumor of neuroectodermal origin, seen largely in the paediatric population and rarely reported in adults. Though the incidence of second malignancies is common in retinoblastoma, medulloepithelioma as a second malignancy in retinoblastoma survivors is rare, with only one case reported so far. Herein, we present a case of a 29-year-old patient presenting with medulloepithelioma of the right orbit, arising in the radiation field of previously treated retinoblastoma. This case was also peculiar in that though the origin of tumor was in the eyeball it had a very aggressive clinical course.

How Eye-Preserving Therapy Affects Long-Term Overall Survival in Heritable Retinoblastoma Survivors

Purpose

Intraocular retinoblastoma is curable, but survivors with a heritable predisposition are at high risk for second malignancies. Because second malignancies are associated with high mortality, prognostic factors for second malignancy influence long-term overall survival. This study investigates the impact of all types of eye-preserving therapies on long-term survival in the complete German cohort of patients with heritable retinoblastoma.

Patients and Methods

Overall survival, disease staging using international scales, time period of diagnosis, and treatment type were analyzed in the 633 German children treated at the national reference center for heritable retinoblastoma.

Results

The 5-year overall survival of children diagnosed in Germany with heritable retinoblastoma between 1940 and 2008 was 93.2% (95% CI, 91.2% to 95.1%), but long-term mortality was increased compared with patients with nonheritable disease. Overall survival correlated with tumor staging, and 92% of patients were diagnosed with a favorable tumor stage (International Retinoblastoma Staging System stage 0 or I). Despite a 5-year overall survival of 97.4% (95% CI, 96.0% to 98.8%) in patients with stage 0 or I, only 79.5% (95% CI, 74.2% to 84.8%) of these patients survived 40 years after diagnosis. Long-term overall survival was reduced in children treated with eye-preserving radiotherapy compared with enucleation alone, and adding chemotherapy aggravated this effect.

Conclusion

The benefits of preserving vision must be balanced with the impact of eye-preserving treatments on long-term survival in heritable retinoblastoma, and the genetic background of the patient influences choice of eye-preserving treatment. Germline RB1 genetic analysis is important to identify heritable retinoblastoma among unilateral retinoblastoma cases. Eye-preserving radiotherapy should be carefully considered in patients with germline RB1 mutations. Life-long oncologic follow-up is crucial for all retinoblastoma survivors, and less detrimental eye-preserving therapies must be developed.

Update on Ophthalmic Oncology 2014: Retinoblastoma and Uveal Melanoma

PURPOSE

The aim of this study was to review peer-reviewed articles on ophthalmic oncology (specifically retinoblastoma and uveal melanoma) published from January to December 2014.

DESIGN

This study is a literature review.

METHODS

The terms retinoblastoma and uveal melanoma were used in a MEDLINE literature search. Abstracts were studied, and the most relevant articles were selected for inclusion and further in-depth review.

RESULTS

In retinoblastoma, more eyes are being salvaged due to intravitreal melphalan. The year 2014 marks a deepening in our understanding of the biological basis of the disease and the cell of origin. Knowledge on the genetic underpinnings of uveal melanoma has broadened to include other pathways, interactions, and potential therapeutic targets.

CONCLUSIONS

In 2014, there were valuable advancements in our knowledge of retinoblastoma and uveal melanoma. Some of these resulted in improved patient management.

Sarcomas Associated With Genetic Cancer Predisposition Syndromes: A Review

: Sarcomas are rare mesenchymal malignancies that demonstrate great clinical and biological heterogeneity. A variety of sarcomas develop in the context of well-defined heritable cancer predisposition syndromes, associations that are often overlooked, given the rarity and diversity of sarcomas and the equivalent relative infrequency of cancer genetic syndromes. This review describes in detail selected heritable cancer predisposition syndromes that are known to be associated with sarcomas. Beyond the molecular and clinical features that define each syndrome, disparities in clinical presentation, natural history, and treatment of syndrome-associated compared with otherwise histologically identical sporadic sarcomas will be described. The clinical approach to selected sarcoma subsets with a view to identifying possible associations with these syndromes will then be described. Although the treatment of the majority of sarcomas will not differ significantly between sporadic cases and those associated with predisposition syndromes, knowledge of features such as unique anatomic sites of affliction or excess toxicities with particular cytotoxic therapies can facilitate alterations in therapeutic strategies to maximize efficacy and minimize toxicity. In addition, recognition of cancer genetic predisposition syndrome will allow patients and their relatives to undertake appropriate genetic counseling and testing, as well as screening, surveillance, and interventional measures, as needed. Situating sarcomas within the genetic endowment of particular patients-specifically that which confers a higher risk of malignancy-will enable clinicians to better manage the patient as a whole, complementing the great efforts currently routinely undertaken to genomically characterize somatic tumor changes with a view to achieving the dream of personalized medicine.

IMPLICATIONS FOR PRACTICE

Sarcomas are uncommon malignancies that often occur sporadically but can also arise in the setting of a recognized heritable cancer predisposition syndrome. Identification of such associations when present can facilitate refinement and optimization of treatment strategies for the sarcoma so as to minimize toxicity and maximize efficacy. Discerning genetic predisposition can also facilitate institution of genetic counseling, as well as screening or surveillance schema for both the patient and his or her relatives, if required. Vigilance for these syndromes has the potential to significantly enhance the quality and comprehensiveness of sarcoma clinical management.

Pediatric Malignant Bone Tumors: A Review and Update on Current Challenges, and Emerging Drug Targets

Osteosarcoma (OS) and the Ewing sarcoma family of tumors (ESFT) are the most common malignant bone tumors in children and adolescents. While significant improvements in survival have been seen in other pediatric malignancies the treatment and prognosis for pediatric bone tumors has remained unchanged for the past 3 decades. This review and update of pediatric malignant bone tumors will provide a general overview of osteosarcoma and the Ewing sarcoma family of tumors, discuss bone tumor genomics, current challenges, and emerging drug targets.

Cause-specific long-term mortality in survivors of childhood cancer in Switzerland: A population-based study

Survivors of childhood cancer have a higher mortality than the general population. We describe cause‐specific long‐term mortality in a population‐based cohort of childhood cancer survivors. We included all children diagnosed with cancer in Switzerland (1976–2007) at age 0–14 years, who survived ≥5 years after diagnosis and followed survivors until December 31, 2012. We obtained causes of death (COD) from the Swiss mortality statistics and used data from the Swiss general population to calculate age‐, calendar year‐, and sex‐standardized mortality ratios (SMR), and absolute excess risks (AER) for different COD, by Poisson regression. We included 3,965 survivors and 49,704 person years at risk. Of these, 246 (6.2%) died, which was 11 times higher than expected (SMR 11.0). Mortality was particularly high for diseases of the respiratory (SMR 14.8) and circulatory system (SMR 12.7), and for second cancers (SMR 11.6). The pattern of cause‐specific mortality differed by primary cancer diagnosis, and changed with time since diagnosis. In the first 10 years after 5‐year survival, 78.9% of excess deaths were caused by recurrence of the original cancer (AER 46.1). Twenty‐five years after diagnosis, only 36.5% (AER 9.1) were caused by recurrence, 21.3% by second cancers (AER 5.3) and 33.3% by circulatory diseases (AER 8.3). Our study confirms an elevated mortality in survivors of childhood cancer for at least 30 years after diagnosis with an increased proportion of deaths caused by late toxicities of the treatment. The results underline the importance of clinical follow‐up continuing years after the end of treatment for childhood cancer.

What's new?

As survivors of childhood cancer age, they are more likely to die prematurely than their peers. The causes of early death, however, are not fully understood, particularly for recently diagnosed children, who may benefit from newer treatment strategies. This study shows that for at least three decades after diagnosis, childhood cancer survivors suffer increased mortality. Disease recurrence initially accounts for the greatest proportion of deaths but is supplanted over time by late treatment‐related toxicities, including second cancers. The findings draw attention to the significance of lifelong follow‐up among survivors of childhood cancer, especially for high‐risk individuals.

Chronic medical conditions in adult survivors of retinoblastoma: Results of the Retinoblastoma Survivor Study

BACKGROUND

Limited data are available regarding long-term morbidity in adult survivors of retinoblastoma (Rb).

METHODS

The Retinoblastoma Survivor Study is a retrospective cohort of adult survivors of Rb diagnosed between 1932 and 1994. Participants completed a comprehensive questionnaire adapted from the Childhood Cancer Survivor Study surveys. Chronic conditions were classified using the National Cancer Institute's Common Terminology Criteria for Adverse Events (version 4.03). Multivariate Poisson regression was used to compare survivors of Rb with 2377 non-Rb controls, consisting of the Childhood Cancer Survivor Study sibling cohort and survivors with bilateral versus unilateral disease.

RESULTS

Survivors of Rb (53.6% with bilateral disease) and non-Rb controls had a mean age of 43.3 years (standard deviation, 11 years) and 37.6 years (SD, 8.6 years), respectively, at the time of study enrollment. At a median follow-up of 42 years (range, 15-75 years), 86.6% of survivors of Rb had at least 1 condition and 71.1% had a severe/life-threatening (grade 3-4) condition. The adjusted relative risk (RR) of a chronic condition in survivors compared with non-Rb controls was 1.4 (95% confidence interval [95% CI], 1.3-1.4; P<.01); for a grade 3 to 4 condition, the RR was 7.6 (95% CI, 6.4-8.9; P<.01). Survivors were at an excess risk regardless of laterality. After stratifying by laterality and excluding ocular conditions and second malignant neoplasms (SMNs), only those with bilateral disease were found to be at an increased risk of any nonocular, non-SMN condition (RR, 1.2; 95% CI, 1.1-1.2) and for grade 3 to 4 nonocular, non-SMN conditions (RR, 1.7; 95% CI, 1.2-2.5).

CONCLUSIONS

Survivors of Rb have an increased risk of chronic conditions compared with non-Rb controls. After excluding ocular conditions and SMNs, this excess risk was found to persist only for those with bilateral disease. Cancer 2016;122:773-781. © 2016 American Cancer Society.

Advanced Unilateral Retinoblastoma: The Impact of Ophthalmic Artery Chemosurgery on Enucleation Rate and Patient Survival at MSKCC

Purpose

To report on the influence of ophthalmic artery chemosurgery (OAC) on enucleation rates, ocular and patient survival from metastasis and impact on practice patterns at Memorial Sloan Kettering for children with advanced intraocular unilateral retinoblastoma.

Patients and Methods

Single-center retrospective review of all unilateral retinoblastoma patients with advanced intraocular retinoblastoma treated at MSKCC between our introduction of OAC (May 2006) and December 2014. End points were ocular survival, patient survival from metastases and enucleation rates.

Results

156 eyes of 156 retinoblastoma patients were included. Primary enucleation rates have progressively decreased from a rate of >95% before OAC to 66.7% in the first year of OAC use to the present rate of 7.4%. The percent of patients receiving OAC has progressively increased from 33.3% in 2006 to 92.6% in 2014. Overall, ocular survival was significantly better in eyes treated with OAC in the years 2010–2014 compared to 2006–2009 (p = 0.023, 92.7% vs 68.0% ocular survival at 48 months). There have been no metastatic deaths in the OAC group but two patients treated with primary enucleation have died of metastatic disease.

Conclusion

OAC was introduced in 2006 and its impact on patient management is profound. Enucleation rates have decreased from over 95% to less than 10%. Our ocular survival rate has also significantly and progressively improved since May 2006. Despite treating more advanced eyes rather then enucleating them patient survival has not been compromised (there have been no metastatic deaths in the OAC group). In our institution, enucleation is no longer the most common treatment for advanced unilateral retinoblastoma.

Characterization and pharmacologic targeting of EZH2, a fetal retinal protein and epigenetic regulator, in human retinoblastoma

Retinoblastoma (RB) is the most common primary intraocular cancer in children, and the third most common cancer overall in infants. No molecular-targeted therapy for this lethal tumor exists. Since the tumor suppressor RB1, whose genetic inactivation underlies RB, is upstream of the epigenetic regulator EZH2, a pharmacologic target for many solid tumors, we reasoned that EZH2 might regulate human RB tumorigenesis. Histologic and immunohistochemical analyses were performed using an EZH2 antibody in sections from 43 samples of primary, formalin-fixed, paraffin-embedded human RB tissue, cryopreserved mouse retina, and in whole cell lysates from human RB cell lines (Y79 and WERI-Rb1), primary human fetal retinal pigment epithelium (RPE) and fetal and adult retina, mouse retina and embryonic stem (ES) cells. Although enriched during fetal human retinal development, EZH2 protein was not present in the normal postnatal retina. However, EZH2 was detected in all 43 analyzed human RB specimens, indicating that EZH2 is a fetal protein expressed in postnatal human RB. EZH2 expression marked single RB cell invasion into the optic nerve, a site of invasion whose involvement may influence the decision for systemic chemotherapy. To assess the role of EZH2 in RB cell survival, human RB and primary RPE cells were treated with two EZH2 inhibitors (EZH2i), GSK126 and SAH-EZH2 (SAH). EZH2i impaired intracellular adenosine triphosphate (ATP) production, an indicator of cell viability, in a time and dose-dependent manner, but did not affect primary human fetal RPE. Thus, aberrant expression of a histone methyltransferase protein is a feature of human RB. This is the first time this mechanism has been implicated for an eye, adnexal, or orbital tumor. The specificity of EZH2i toward human RB cells, but not RPE, warrants further in vivo testing in animal models of RB, especially those EZH2i currently in clinical trials for solid tumors and lymphoma.

Pediatric second primary malignancies after retinoblastoma treatment

BACKGROUND

Children with retinoblastoma carry a high risk to develop second primary malignancies in childhood and adolescence. This study characterizes the type of pediatric second primary malignancies after retinoblastoma treatment and investigates the impact of different treatment strategies and prognostic factors at presentation.

PROCEDURE

All national patients treated for retinoblastoma at the German referral center with a current age of 6-27 years were invited to participate in a study to characterize late effects.

RESULTS

Data on pediatric second primary malignancies were recorded from 488 patients. Ten developed a malignancy before the age of 18 years. For children with heterozygous oncogenic RB1 alteration (heritable retinoblastoma), the cumulative incidence to develop a second malignancy at the age of 10 years was 5.2% (95% CI 1.7; 8.7%). This results in an elevated risk for sarcoma (n = 4) (SIR 147.98; 95% CI 39.81; 378.87) and leukemia (n = 4) (SIR 41.38; 95% CI 11.13; 105.95). Neither the functional type of the RB1 alteration nor its origin showed a significant impact. Treatment modality influenced incidence, latency, and type of malignancy. Previous radiotherapy increased the risk for solid tumors and 3 of 91 children developed acute leukemia after chemotherapy. However, 2 of 10 malignancies were diagnosed in patients with heritable retinoblastoma but without previous chemotherapy or external beam radiotherapy.

CONCLUSIONS

Screening for second primary malignancy is an important part of pediatric oncological follow-up in patients with heritable retinoblastoma. For patients with sporadic unilateral retinoblastoma, genetic information influences treatment decisions and allows tailoring of follow-up schedules.

Retinoblastoma

Retinoblastoma is a rare cancer of the infant retina that is diagnosed in approximately 8,000 children each year worldwide. It forms when both retinoblastoma gene (RB1) alleles are mutated in a susceptible retinal cell, probably a cone photoreceptor precursor. Loss of the tumour-suppressive functions of the retinoblastoma protein (pRB) leads to uncontrolled cell division and recurrent genomic changes during tumour progression. Although pRB is expressed in almost all tissues, cone precursors have biochemical and molecular features that may sensitize them to RB1 loss and enable tumorigenesis. Patient survival is >95% in high-income countries but <30% globally. However, outcomes are improving owing to increased disease awareness for earlier diagnosis, application of new guidelines and sharing of expertise. Intra-arterial and intravitreal chemotherapy have emerged as promising methods to salvage eyes that with conventional treatment might have been lost. Ongoing international collaborations will replace the multiple different classifications of eye involvement with standardized definitions to consistently assess the eligibility, efficacy and safety of treatment options. Life-long follow-up is warranted, as survivors of heritable retinoblastoma are at risk for developing second cancers. Defining the molecular consequences of RB1 loss in diverse tissues may open new avenues for treatment and prevention of retinoblastoma, as well as second cancers, in patients with germline RB1 mutations.

Approaches to reduce the long-term burden of treatment-related complications in survivors of childhood cancer

Advances in diagnostics, treatment strategies, and supportive care have contributed to a marked improvement in outcomes for children with cancer. This has resulted in a growing number of long-term childhood cancer survivors. Currently there are over 360,000 individuals who are survivors of childhood cancer in the United States. However, treatment for patients with childhood cancer with chemotherapy, radiation, and/or hematopoietic stem cell transplantation can result in health-related complications that may not become evident until years after completion of treatment. As a result, several initiatives have been established to help standardize the surveillance for treatment-related late effects in childhood cancer survivors. This review highlights emerging concepts related to commonly reported late effects, such as subsequent malignant neoplasms, cardiovascular disease, and endocrinopathies. It also discusses relevant population-based screening strategies to mitigate the long-term health-related burden in vulnerable populations of survivors.

Direct involvement of retinoblastoma family proteins in DNA repair by non-homologous end-joining

Deficiencies in DNA double-strand break (DSB) repair lead to genetic instability, a recognized cause of cancer initiation and evolution. We report that the retinoblastoma tumor suppressor protein (RB1) is required for DNA DSB repair by canonical non-homologous end-joining (cNHEJ). Support of cNHEJ involves a mechanism independent of RB1's cell-cycle function and depends on its amino terminal domain with which it binds to NHEJ components XRCC5 and XRCC6. Cells with engineered loss of RB family function as well as cancer-derived cells with mutational RB1 loss show substantially reduced levels of cNHEJ. RB1 variants disabled for the interaction with XRCC5 and XRCC6, including a cancer-associated variant, are unable to support cNHEJ despite being able to confer cell-cycle control. Our data identify RB1 loss as a candidate driver of structural genomic instability and a causative factor for cancer somatic heterogeneity and evolution.

How cell death shapes cancer

Apoptosis has been established as a mechanism of anti-cancer defense. Members of the BCL-2 family are critical mediators of apoptotic cell death in health and disease, often found to be deregulated in cancer and believed to lead to the survival of malignant clones. However, over the years, a number of studies pointed out that a model in which cell death resistance unambiguously acts as a barrier against malignant disease might be too simple. This is based on paradoxical observations made in tumor patients as well as mouse models indicating that apoptosis can indeed drive tumor formation, at least under certain circumstances. One possible explanation for this phenomenon is that apoptosis can promote proliferation critically needed to compensate for cell loss, for example, upon therapy, and to restore tissue homeostasis. However, this, at the same time, can promote tumor development by allowing expansion of selected clones. Usually, tissue resident stem/progenitor cells are a major source for repopulation, some of them potentially carrying (age-, injury- or therapy-induced) genetic aberrations deleterious for the host. Thereby, apoptosis might drive genomic instability by facilitating the emergence of pathologic clones during phases of proliferation and subsequent replication stress-associated DNA damage. Tumorigenesis initiated by repeated cell attrition and repopulation, as confirmed in different genetic models, has parallels in human cancers, exemplified in therapy-induced secondary malignancies and myelodysplastic syndromes in patients with congenital bone marrow failure syndromes. Here, we aim to review evidence in support of the oncogenic role of stress-induced apoptosis.