Second primary tumors in patients with retinoblastoma. A review of the literature

Retinoblastoma: present scenario and future challenges

With an average incidence of 1 in every 18,000 live births, retinoblastoma is a rare type of intraocular tumour found to affect patients during their early childhood. It is curable if diagnosed at earlier stages but can become life-threateningly malignant if not treated timely. With no racial or gender predisposition, or even environmental factors known to have been involved in the incidence of the disease, retinoblastoma is often considered a clinical success story in pediatric oncology. The survival rate in highly developed countries is higher than 95% and they have achieved this because of the advancement in the development of diagnostics and treatment techniques. This includes developing the already existing techniques like chemotherapy and embarking on new strategies like enucleation, thermotherapy, cryotherapy, etc. Early diagnosis, studies on the etiopathogenesis and genetics of the disease are the need of the hour for improving the survival rates. According to the Knudson hypothesis, also known as the two hit hypothesis, two hits on the retinoblastoma susceptibility (RB) gene is often considered as the initiating event in the development of the disease. Studies on the molecular basis of the disease have also led to deciphering the downstream events and thus in the discovery of biomarkers and related targeted therapies. Furthermore, improvements in molecular biology techniques enhanced the development of efficient methods for early diagnosis, genetic counseling, and prevention of the disease. In this review, we discuss the genetic and molecular features of retinoblastoma with a special emphasis on the mutation leading to the dysregulation of key signaling pathways involved in cell proliferation, DNA repair, and cellular plasticity. Also, we describe the classification, clinical and epidemiological relevance of the disease, with an emphasis on both the traditional and innovative treatments to tackle retinoblastoma. Video Abstract.

Secondary osteosarcoma: a challenge indeed

BACKGROUND

The risk of survivors developing a secondary bone sarcoma after being treated for pediatric cancers is well established. The aim of this study was to examine the clinical characteristics and outcomes of patients with secondary osteosarcoma (SOS).

METHODS

The study concerns survivors of childhood and adolescence primary neoplasms (PN) treated with chemotherapy, with or without radiotherapy and surgery, subsequently diagnosed with SOS.

RESULTS

We identified 26 patients (13 females, 13 males) who developed SOS a median 7.3 years after being diagnosed with a PN (5/7 of these patients tested for Li-Fraumeni and found positive for the syndrome). The sample's median age was 8.0 and 15.0 years when their PN and SOS were diagnosed, respectively. To treat their PN, 24 out of 26 patients had been given radiotherapy, and 19 had received chemotherapy including doxorubicin. A considerable number of SOS occurred at unfavorable sites (nine hip bone, six skull). All but one patient received chemotherapy with tailored schedules, omitting doxorubicin in 19 cases. Eighteen of the 26 patients underwent surgery. The 5- and 10-year overall survival and probabilities after the diagnosis of SOS (95% confidence interval) were 50% (32.7-76.5%) and 38.9% (22.4-67.4%); 5- and 10-year progression-free survival was 47% (29.9-73.7%) and 35.2% (19.3-64.4%), respectively.

CONCLUSIONS

The survival rates after SOS are lower than in patients with primary osteosarcoma, but not negligible. It is therefore mandatory to discuss the best choice of treatment for such patients at a referral center, in terms of their chances of cure and quality of life.

Retinoblastoma protein regulates carcinogen susceptibility at heterochromatic cancer driver loci

Carcinogenic insult, such as UV light exposure, creates DNA lesions that evolve into mutations if left unrepaired. These resulting mutations can contribute to carcinogenesis and drive malignant phenotypes. Susceptibility to carcinogens (i.e., the propensity to form a carcinogen-induced DNA lesion) is regulated by both genetic and epigenetic factors. Importantly, carcinogen susceptibility is a critical contributor to cancer mutagenesis. It is known that mutations can be prevented by tumor suppressor regulation of DNA damage response pathways; however, their roles carcinogen susceptibility have not yet been reported. In this study, we reveal that the retinoblastoma (RB1) tumor suppressor regulates UV susceptibility across broad regions of the genome. In particular, centromere and telomere-proximal regions exhibit significant increases in UV lesion susceptibility when RB1 is deleted. Several cancer-related genes are located within genomic regions of increased susceptibility, including telomerase reverse transcriptase, TERT, thereby accelerating mutagenic potential in cancers with RB1 pathway alterations. These findings reveal novel genome stability mechanisms of a tumor suppressor and uncover new pathways to accumulate mutations during cancer evolution.

Recommendations for Long-Term Follow-up of Adults with Heritable Retinoblastoma

PURPOSE

To generate recommendations for long-term follow-up of adult survivors of heritable retinoblastoma.

DESIGN

We convened a meeting of providers from retinoblastoma centers around the world to review the state of the science and to evaluate the published evidence.

PARTICIPANTS

Retinoblastoma is a rare childhood cancer of the retina. Approximately 40% of retinoblastoma cases are heritable, resulting from a germline mutation in RB1. Dramatic improvements in treatment and supportive care have resulted in a growing adult survivor population. However, survivors of heritable retinoblastoma have a significantly increased risk of subsequent malignant neoplasms, particularly bone and soft tissue sarcomas, uterine leiomyosarcoma, melanomas, and radiotherapy-related central nervous system tumors, which are associated with excess morbidity and mortality. Despite these risks, no surveillance recommendations for this population currently are in place, and surveillance practices vary widely by center.

METHODS

Following the Institute of Medicine procedure for clinical practice guideline development, a PubMed, EMBASE, and Web of Science search was performed, resulting in 139 articles; after abstract and full-text review, 37 articles underwent detailed data abstraction to quantify risk and evidence regarding surveillance, if available. During an in-person meeting, evidence was presented and discussed, resulting in consensus recommendations.

MAIN OUTCOME MEASURES

Diagnosis and mortality from subsequent neoplasm.

RESULTS

Although evidence for risk of subsequent neoplasm, especially sarcoma and melanoma, was significant, evidence supporting routine testing of asymptomatic survivors was not identified. Skin examination for melanoma and prompt evaluation of signs and symptoms of head and neck disease were determined to be prudent.

CONCLUSIONS

This review of the literature confirmed some of the common second cancers in retinoblastoma survivors but found little evidence for a benefit from currently available surveillance for these malignancies. Future research should incorporate international partners, patients, and family members.

Second primary tumors in retinoblastoma survivors: a study of 7 Asian Indian patients

PURPOSE

To assess the incidence, types, and outcomes of second primary tumors (SPT) in cases of retinoblastoma (RB) from a referral Tertiary eye care center METHODS: Retrospective chart review of 7 cases RESULTS: All 7 (100%) cases had bilateral RB at presentation. The mean age at diagnosis of RB was 16 months (median 7 months; range 5-72 months). Treatment of RB with intravenous chemotherapy was noted in 3 (43%) patients, 1 (14%) patient had received external beam radiotherapy (EBRT) to the orbit, 1 (14%) patient had received a combination of chemotherapy and orbital EBRT, while 4 (57%) patients had undergone primary enucleation of the worse eye and focal treatment of the better eye. The mean age at detection of SPT was 15 years (median 8 years; range 6-46 years). The mean time interval between diagnosis of RB and SPT was 13 years (median 7 years; range 1-41 years). The SPT's included osteosarcoma of long bone (n = 2), eyelid sebaceous gland carcinoma (n = 2), ventricular ependymoma (n = 1), orbital neuroblastoma (n = 1), and acute lymphoblastic leukemia (n = 1). All patients received treatment for the SPT with either surgical excision (n = 2), intravenous chemotherapy (n = 1), or a combination of surgery/chemotherapy/radiotherapy (n = 4). Over a mean follow-up period of 8 years (median 8 years; range 4-11 years), one (14%) patient died, while other 6 (86%) patients are alive and well.

CONCLUSION

Though the incidence of SPT's in cases of RB is rare, life-long follow-up is mandatory in at-risk patients.

Conservative management of retinoblastoma: Challenging orthodoxy without compromising the state of metastatic grace. "Alive, with good vision and no comorbidity"

Retinoblastoma is lethal by metastasis if left untreated, so the primary goal of therapy is to preserve life, with ocular survival, visual preservation and quality of life as secondary aims. Historically, enucleation was the first successful therapeutic approach to decrease mortality, followed over 100 years ago by the first eye salvage attempts with radiotherapy. This led to the empiric delineation of a window for conservative management subject to a "state of metastatic grace" never to be violated. Over the last two decades, conservative management of retinoblastoma witnessed an impressive acceleration of improvements, culminating in two major paradigm shifts in therapeutic strategy. Firstly, the introduction of systemic chemotherapy and focal treatments in the late 1990s enabled radiotherapy to be progressively abandoned. Around 10 years later, the advent of chemotherapy in situ, with the capitalization of new routes of targeted drug delivery, namely intra-arterial, intravitreal and now intracameral injections, allowed significant increase in eye preservation rate, definitive eradication of radiotherapy and reduction of systemic chemotherapy. Here we intend to review the relevant knowledge susceptible to improve the conservative management of retinoblastoma in compliance with the "state of metastatic grace", with particular attention to (i) reviewing how new imaging modalities impact the frontiers of conservative management, (ii) dissecting retinoblastoma genesis, growth patterns, and intraocular routes of tumor propagation, (iii) assessing major therapeutic changes and trends, (iv) proposing a classification of relapsing retinoblastoma, (v) examining treatable/preventable disease-related or treatment-induced complications, and (vi) appraising new therapeutic targets and concepts, as well as liquid biopsy potentiality.

Metabolite systems profiling identifies exploitable weaknesses in retinoblastoma

Retinoblastoma (RB) is a childhood eye cancer. Currently, chemotherapy, local therapy, and enucleation are the main ways in which these tumors are managed. The present work is the first study that uses constraint-based reconstruction and analysis approaches to identify and explain RB-specific survival strategies, which are RB tumor specific. Importantly, our model-specific secretion profile is also found in RB1-depleted human retinal cells in vitro and suggests that novel biomarkers involved in lipid metabolism may be important. Finally, RB-specific synthetic lethals have been predicted as lipid and nucleoside transport proteins that can aid in novel drug target development.

Risk of Subsequent Bone Cancers Among 69 460 Five-Year Survivors of Childhood and Adolescent Cancer in Europe

Introduction

We investigate the risks of subsequent primary bone cancers after childhood and adolescent cancer in 12 European countries. For the first time, we satisfactorily address the risks beyond 40 years from diagnosis and beyond 40 years of age among all survivors.

Methods

This largest-ever assembled cohort comprises 69 460 five-year survivors of cancer diagnosed before age 20 years. Standardized incidence ratios, absolute excess risks, and multivariable-adjusted relative risks and relative excess risks were calculated. All statistical tests were two-sided.

Results

Overall, survivors were 21.65 times (95% confidence interval = 18.97 to 24.60 times) more likely to be diagnosed with a subsequent primary bone cancer than expected from the general population. The greatest excess numbers of bone cancers were observed after retinoblastoma, bone sarcoma, and soft tissue sarcoma. The excess number of bone cancers declined linearly with both years since diagnosis and attained age (all P < .05). Beyond 40 years from diagnosis and age 40 years, there were at most 0.45 excess bone cancers among all survivors per 10 000 person-years at risk; beyond 30 years from diagnosis and age 30 years, there were at most 5.02 excess bone cancers after each of retinoblastoma, bone sarcoma, and soft tissue sarcoma, per 10 000 person-years at risk.

Conclusions

For all survivors combined and the cancer groups with the greatest excess number of bone cancers, the excess numbers observed declined with both age and years from diagnosis. These results provide novel, reliable, and unbiased information about risks and risk factors among long-term survivors of childhood and adolescent cancer.

MicroRNA‑382 inhibits cell proliferation and invasion of retinoblastoma by targeting BDNF‑mediated PI3K/AKT signalling pathway

It has previously been demonstrated that multiple microRNAs (miRNAs or miRs) are aberrantly expressed in retinoblastoma (RB) and contribute to RB initiation and progression. miR‑382 has been revealed to be aberrantly expressed and therefore exhibits a key role in the progression of various types of cancer. However, the expression pattern, functional roles and underlying molecular mechanism of miR‑382 in RB remain unknown. The present study investigated the expression levels of miR‑382 and its effects on RB cells and the underlying regulatory mechanism of its action. It was demonstrated that miR‑382 was downregulated in RB tissues and cell lines. Upregulation of miR‑382 inhibited RB cell proliferation and invasion in vitro. Additionally, brain‑derived neurotrophic factor (BDNF) was identified as a novel target of miR‑382 in RB. BDNF was upregulated in RB tissues and negatively associated with miR‑382 expression levels. Furthermore, BDNF overexpression rescued the tumour‑suppressing effects on RB cells induced by miR‑382. miR‑382 inactivated the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signalling pathway in RB. These findings suggested that miR‑382 serves as a tumour suppressor in RB, in part, by targeting the BDNF‑mediated PI3K/AKT signalling pathway. The results of the present study suggest a potential therapeutic strategy for treating RB patients in the future.

Trilateral retinoblastoma: A systematic review of 211 cases

We conducted a systematic review of 72 studies to characterize trilateral retinoblastomas. Kaplan-Meier analysis was used to estimate survival, and statistical significance was assessed by using a log-rank test. We analyzed 211 cases of trilateral retinoblastomas. The average age of onset of retinoblastoma was 0.79 ± 1.38 years, and the average latency period between the onset of retinoblastomas and trilateral retinoblastomas was 1.49 ± 1.76 years. The brain tumors were found before the retinoblastoma diagnosis in 6 cases (3.1%), concurrently in 61 cases (32.1%), and after the retinoblastoma diagnosis in 123 cases (64.7%). Pineal tumors were found in 155 cases (73.4%) and sellar tumors in 46 cases (21.8%). The overall median survival was 10.3 months (95% CI, 8.5-13) and the 5-year survival rate was 15.7%. Central nervous system symptoms were variable and associated with shorter survival in univariate and multivariate analyses. The survival time in patients who received high-dose chemotherapy with stem cell transplant was significantly longer (p = 0.0067) than that of with or without conventional chemotherapy. Twelve long-term survivors were reported, and of these, six patients were treated with high-dose chemotherapy with stem cell transplant and six patients were treated with conventional chemotherapy. It is important that survivors continue to undergo regular medical surveillance in order to detect trilateral retinoblastoma at a potentially curative stage. Trilateral retinoblastoma patients with an irradiation history had shorter survival than those without irradiation history for retinoblastoma. High-dose chemotherapy should be considered as a potential treatment option for trilateral retinoblastomas.

MicroRNA-320 inhibits cell proliferation, migration and invasion in retinoblastoma by targeting specificity protein 1

Research into the expression and function of microRNAs (miRNAs/miR) in human cancer has provided novel insights into the molecular mechanisms underlying carcinogenesis and cancer progression. Aberrant miRNA expression has been reported in retinoblastoma (RB) and several other types of human cancer. The present study demonstrated that miR‑320 is significantly downregulated in RB tissues and cell lines. Furthermore, overexpression of miR‑320 was demonstrated to inhibit proliferation, migration and invasion of RB cells. Bioinformatic analysis identified specificity protein 1 (SP1) as a potential target gene of miR‑320. Luciferase reporter assay confirmed that the SP1 3'‑untranslated region contains a direct binding site for miR‑320, and restoration of miR‑320 expression decreased the mRNA and protein expression levels of SP1. Notably, SP1 silencing induced a similar effect on the proliferation, migration and invasion of RB cells as that observed with miR‑320 overexpression, further supporting the hypothesis that SP1 is a direct functional target of miR‑320 in RB. In conclusion, these findings indicate that miR‑320 may be an effective therapeutic target for the treatment of RB.

Giant gastric lipossarcoma: case report and review of the literature

Liposarcoma is one of the most common soft tissue sarcomas in adults, occurring in 15 to 20% of all patients with sarcoma. Primary liposarcoma of the stomach is rare. We report a case of patient with giant gastric liposarcoma who underwent surgery after a gastrointestinal bleeding. Preoperative hystopathological diagnosis was not established, even after three biopsy attempts. We discuss differential diagnosis, genetic causes, diagnosis strategies and treatment.

Unusually very late-onset new growth of intraocular retinoblastoma: A case report and review of literature

Purpose

To report a patient who presented with a very late-onset new growth of intraocular retinoblastoma, which occurred 11 years after the initial combined treatment.

Observations

A 12-year-old monoophthalmic female patient presented with bilateral familial retinoblastoma showing new growth of intraocular tumor after 11 years of complete regression following combined local and systemic treatments. The new tumor growth was treated with diode laser transpupillary thermotherapy, ruthenium-106 plaque radiotherapy and adjuvant intravenous chemotherapy and the tumor regressed.

Conclusions and importance

Despite initial satisfactory treatment and complete regression of the tumor, very late-onset new growth of intraocular retinoblastoma can occur. Hence, life-long follow-up in all patients with retinoblastoma is warranted, given the risk for new tumor formation even later in life. To our knowledge, this is the first report of new growth of intraocular retinoblastoma after regression for more than a decade.

Orbital sarcomas in retinoblastoma patients: recommendations for screening and treatment guidelines

PURPOSE OF REVIEW

Retinoblastoma is the most common primary ocular malignancy in children. Although currently retinoblastoma has an excellent survival rate in developed countries, hereditary retinoblastoma survivors as well as those with a history of radiation therapy as children are at an increased risk for second primary tumors (SPTs), and specifically, for orbital sarcomas. Despite the known increased risk for SPTs in retinoblastoma survivors and the associated morbidity and mortality, no screening or treatment guidelines exist.

RECENT FINDINGS

Understanding of retinoblastoma tumorigenesis and genomic expression has expanded significantly, and treatment has evolved with a shift away from radiotherapy. Until the last two decades, however, radiation was the therapy of choice for patients with bilateral disease. Because both hereditary retinoblastoma and radiation are independent risk factors for the development of SPTs such as sarcomas and these SPTs are often fatal, appropriate surveillance for retinoblastoma survivors is crucial.

SUMMARY

As a result of the excellent survival rates for retinoblastoma patients, it is important to: recognize the risk of sarcoma, particularly in patients with hereditary retinoblastoma and/or prior radiation therapy; establish a screening protocol, such as the one proposed, to maximize early detection; and discuss and develop treatment guidelines for high-risk patients. Future directions of research for these patients will involve the development of molecularly targeted agents and the use of proton radiotherapy.

Recurrent Retinoblastoma With Mandibular Metastasis: A Case Report

Retinoblastoma (RB) is an aggressive intraocular tumor arising from cells of the retina. Infrequently, distant metastasis occurs in advanced stages of the disease. This case report describes the metastasis of the tumor to the mandible, an extremely rare phenomenon. This condition was observed for a recurrent tumor in a patient who initially underwent chemotherapy, making this case report unique and providing new insights into the behavior of this tumor. An overview of the management of a metastatic RB also is discussed.

Acute lymphoblastic leukemia as second primary tumor in a patient with retinoblastoma

Second primary tumor (SPT) is defined as a second tumor that presents either simultaneously or after the diagnosis of an index tumor. Second primary malignancies are the leading cause of death in patients with heritable retinoblastoma (RB). Acute lymphoblastic leukemia (ALL), as SPT in RB patients, is extremely rare. To the best of our knowledge, only five cases of ALL as SPT in patients with RB has been documented in the literature. Herein, we report a case of a 6-year-old girl with bilateral RB, who developed ALL during the course of treatment of RB. This case highlights the importance of reviewing blood investigations regularly to diagnose leukemia as SPT in RB and also the necessity for proper counseling and lifelong follow-up in these patients.

Second primary osteosarcomas in patients with retinoblastoma

OBJECTIVE

Second primary malignancies have become the leading cause of death in retinoblastoma survivors. Although osteosarcoma is the most common second malignancy, little is known about its clinical and therapeutic features.

METHODS

We retrospectively reviewed a database of patients with retinoblastoma and osteosarcoma occurring as a second malignancy between 1964 and 2010 at the National Cancer Center Hospital of Japan.

RESULTS

Among 857 patients with retinoblastoma registered in the database, 10 (1.1%) developed osteosarcoma as a second malignancy. The median age at the onset of retinoblastoma was 3 months, being bilateral in nine patients and unilateral in one. Systemic chemoreduction was performed in three patients and intra-arterial chemotherapy in six; all patients received external beam radiotherapy. The median age at the onset of second primary osteosarcoma was 11.2 years; four were radiation-related and six were located in an extremity. Among five patients treated at our institute, four patients with tumors on an extremity were treated by wide resection with neoadjuvant and adjuvant chemotherapy. Three of these four patients (75%) were good responders to high-dose methotrexate-based multi-agent chemotherapy and survived with no evidence of disease (median follow-up period, 17.3 years). One patient whose temporal bone was affected underwent radiotherapy with chemotherapy but died after local recurrence.

CONCLUSIONS

The clinical outcomes of second primary osteosarcoma in an extremity occurring in retinoblastoma survivors may be more favorable than those of conventional osteosarcoma. Early diagnosis of radiation-related osteosarcoma arising in the craniofacial region should be made at a stage where complete resection is possible.

Secondary osteosarcoma: is there a predilection for the chondroblastic subtype?

Osteosarcoma is the most common form of primary bone cancer in the adolescent and young adult patient population. Outcomes in patients with secondary osteosarcoma are inferior compared with outcomes in patients with primary osteosarcoma. The goal of this study was to investigate whether there is a predilection for the chondroblastic histologic subtype in secondary osteosarcoma. A retrospective chart review was performed to identify cases of secondary osteosarcoma treated at 1 institution from 1991 to 2012. Histologic subtypes were evaluated by a pathologist, and a review of the literature was also performed to identify the histologic subclassification of additional series of secondary osteosarcomas. Of a total of 131 cases of osteosarcoma, 9 (6.9%) were identified as a secondary malignancy. Only 2 cases (22%) were identified as chondroblastic variants, although 6 (67%) showed some degree of chondroid differentiation. Of the 3 cases meeting the criteria for postradiation osteosarcoma, 2 (67%) were identified as chondroblastic variants and all 3 showed some degree of chondroid differentiation. Five other studies evaluating histologic subtypes in postradiation osteosarcoma showed a cumulative frequency of 20% for the chondroblastic variant. Although the study results did not support the hypothesis of an association between secondary osteosarcoma and the chondroblastic subtype, the high proportion of cases of postradiation osteosarcoma with the chondroblastic subtype and the even higher proportion showing some degree of chondroid differentiation are noteworthy features of this disease.

A practice guideline from the American College of Medical Genetics and Genomics and the National Society of Genetic Counselors: referral indications for cancer predisposition assessment

DISCLAIMER

The practice guidelines of the American College of Medical Genetics and Genomics (ACMG) and the National Society of Genetic Counselors (NSGC) are developed by members of the ACMG and NSGC to assist medical geneticists, genetic counselors, and other health-care providers in making decisions about appropriate management of genetic concerns, including access to and/or delivery of services. Each practice guideline focuses on a clinical or practice-based issue and is the result of a review and analysis of current professional literature believed to be reliable. As such, information and recommendations within the ACMG and NSGC joint practice guidelines reflect the current scientific and clinical knowledge at the time of publication, are current only as of their publication date, and are subject to change without notice as advances emerge. In addition, variations in practice, which take into account the needs of the individual patient and the resources and limitations unique to the institution or type of practice, may warrant approaches, treatments, and/or procedures that differ from the recommendations outlined in this guideline. Therefore, these recommendations should not be construed as dictating an exclusive course of management, nor does the use of such recommendations guarantee a particular outcome. Genetic counseling practice guidelines are never intended to displace a health-care provider's best medical judgment based on the clinical circumstances of a particular patient or patient population. Practice guidelines are published by the ACMG or the NSGC for educational and informational purposes only, and neither the ACMG nor the NSGC "approve" or "endorse" any specific methods, practices, or sources of information.Cancer genetic consultation is an important aspect of the care of individuals at increased risk of a hereditary cancer syndrome. Yet several patient, clinician, and system-level barriers hinder identification of individuals appropriate for cancer genetics referral. Thus, the purpose of this practice guideline is to present a single set of comprehensive personal and family history criteria to facilitate identification and maximize appropriate referral of at-risk individuals for cancer genetic consultation. To develop this guideline, a literature search for hereditary cancer susceptibility syndromes was conducted using PubMed. In addition, GeneReviews and the National Comprehensive Cancer Network guidelines were reviewed when applicable. When conflicting guidelines were identified, the evidence was ranked as follows: position papers from national and professional organizations ranked highest, followed by consortium guidelines, and then peer-reviewed publications from single institutions. The criteria for cancer genetic consultation referral are provided in two formats: (i) tables that list the tumor type along with the criteria that, if met, would warrant a referral for a cancer genetic consultation and (ii) an alphabetical list of the syndromes, including a brief summary of each and the rationale for the referral criteria that were selected. Consider referral for a cancer genetic consultation if your patient or any of their first-degree relatives meet any of these referral criteria.

Whole-body magnetic resonance imaging (WB-MRI) as surveillance for subsequent malignancies in survivors of hereditary retinoblastoma: a pilot study

BACKGROUND

Individuals with hereditary retinoblastoma (RB) are at very high risk of developing subsequent malignant neoplasms (SMNs) of which osteosarcoma (OS) is one of the most common. We hypothesized that annual surveillance using whole-body magnetic resonance imaging (WB-MRI) in asymptomatic survivors of hereditary RB would detect SMN of the bone and soft tissues at an early stage.

PROCEDURE

Retrospective review of the results of a WB-MRI screening program in hereditary RB survivors from February 2008 to August 2012. The primary outcome was to determine the sensitivity and specificity of WB-MRI in detecting SMNs.

RESULTS

Twenty-five patients had at least one WB-MRI performed (range: 1-5). First WB-MRI was performed at a median age of 16 years (range: 8-25 years). WB-MRI detected new osseous abnormalities suspicious for malignancy in five patients: two were diagnosed with localized high-grade OS of the extremity and three were found to have benign osseous abnormalities after dedicated imaging (n = 5/5) and/or biopsy (n = 3/5). One patient was diagnosed with secondary OS 3 months after a normal screening WB-MRI exam. Among a total of 41 WB-MRI screening tests performed in survivors of hereditary RB, the sensitivity of detecting SMN was 66.7% and the specificity was 92.1%.

CONCLUSIONS

Preliminary results suggest that annual WB-MRI surveillance detects SMN in survivors of hereditary RB, but with modest sensitivity. Further study is needed to assess the performance of annual surveillance WB-MRIs and whether this modality decreases SMN-related mortality in RB survivors.

The prognosis of osteosarcoma occurring as second malignancy of childhood cancers may be favorable: experience of two cancer centers in Japan

BACKGROUND

Osteosarcoma as second malignancy of childhood cancers rarely occurs, and its clinical characteristics are unclear.

METHODS

Patients with osteosarcoma occurring as second malignancy of childhood cancers were retrospectively surveyed.

RESULTS

Of 323 patients with osteosarcoma registered in the database, 10 (3.1%) had a past history of childhood cancers. The mean age at the onset of the first childhood cancer was 2.7 years, and the diagnosis of the first childhood cancer was adrenocortical carcinoma, malignant teratoma, ovarian carcinoma, Ewing's sarcoma, and rhabdomyosarcoma in 1 patient each, and retinoblastoma in 5 patients. Osteosarcoma as second malignancy occurred 14.6 years after the first childhood cancer on average. Seven patients were alive and 3 died. In 1 patient, the cause of death was related to a complication of treatment for the first childhood cancer. Except for this patient, 7 (77.8%) of 9 patients survived with no disease (mean follow-up period: 10.9 years).

CONCLUSIONS

Attention should be paid to complications of treatment for the first childhood cancer in the treatment for osteosarcoma occurring as second malignancy. The prognosis of osteosarcoma as second malignancy of childhood cancers may be more favorable than that of conventional osteosarcoma.

[Childhood cancer: progress but prognosis still very unequal. Example of Retinoblastoma and high-risk Neuroblastoma]

Children suffering with cancer have a higher probability of cure than adult. Since the 1950's, high cure rates have been achieved following remarkable progress in the overall care of these children. Not only children are more often "cured" than during the past century but they are probably "better cured" with the hope of experiencing less late effects. Nevertheless, there are still large disparities related to tumor diagnosis and regional area on the globe. If retinoblastoma is now cured in about 100% of the cases in industrialized countries, a different figure is seen unfortunately in economically disadvantaged countries. Not only is access to primary care lower, but also ophthalmologic techniques and available cancer treatments are less effective. Nowadays, such high cure rates observed for children with retinoblastoma are not the rule for all children with cancer. For example, despite considerable progress with new innovative treatments, the cure rate of children with metastatic neuroblastoma does not exceed 40%.

RB1 mutation spectrum in a comprehensive nationwide cohort of retinoblastoma patients

BACKGROUND

Retinoblastoma (Rb) is a childhood cancer of the retina, commonly initiated by biallelic inactivation of the RB1 gene. Knowledge of the presence of a heritable RB1 mutation can help in risk management and reproductive decision making. We report here on RB1 mutation scanning in a unique nationwide cohort of Rb patients from the Netherlands.

METHODS

From the 1173 Rb patients registered in the Dutch National Retinoblastoma Register until January 2013, 529 patients from 433 unrelated families could be included. RB1 mutation scanning was performed with different detection methods, depending on the time period.

RESULTS

Our mutation detection methods revealed RB1 mutations in 92% of bilateral and/or familial Rb patients and in 10% of non-familial unilateral cases. Overall an RB1 germline mutation was detected in 187 (43%) of 433 Rb families, including 33 novel mutations. The distribution of the type of mutation was 37% nonsense, 20% frameshift, 21% splice, 9% large indel, 5% missense, 7% chromosomal deletions and 1% promoter. Ten per cent of patients were mosaic for the RB1 mutation. Six three-generation families with incomplete penetrance RB1 mutations were found. We found evidence that two variants, previously described as pathogenic RB1 mutations, are likely to be neutral variants.

CONCLUSIONS

The frequency of the type of mutations in the RB1 gene in our unbiased national cohort is the same as the mutation spectrum described worldwide. Furthermore, our RB1 mutation detection regimen achieves a high scanning sensitivity.

Genes and environment: effects on the development of second malignancies in retinoblastoma survivors

Although it is a rare cancer, retinoblastoma has served as an important model in our understanding of genetic cancer syndromes. All patients with a germinal rb1 mutation possess a risk of the development of second malignancies. Approximately 40-50% of all retinoblastoma cases are considered germinal cases and recent work has indicated that nearly all retinoblastoma patients probably demonstrate a degree of mosaicism for the rb1 mutation, and thus are at risk of secondary malignancies. The risk of the development of these cancers continues throughout the patients' lives due to the loss of a functional RB1 protein and its critical tumor suppressive function in all cells. These cancers can develop in diverse anatomic locations, including the skull and long bones, soft tissues, nasal cavity, skin, orbit, brain, breast and lung. Treatments used for retinoblastoma such as external-beam radiation and chemotherapy can have a significant impact on the risk for and pattern of development of these secondary cancers. Second malignancies are the leading cause of death in germinal retinoblastoma survivors in the USA and thus continue to be an important subject of study in this patient population. Second malignancies following the germinal form of retinoblastoma are the subject of this review.

Structural insights into the mechanism of phosphoregulation of the retinoblastoma protein

The retinoblastoma susceptibility protein RB1 is a key regulator of cell proliferation and fate. RB1 operates through nucleating the formation of multi-component protein complexes involved in the regulation of gene transcription, chromatin structure and protein stability. Phosphorylation of RB1 by cyclin-dependent kinases leads to conformational alterations and inactivates the capability of RB1 to bind partner protein. Using small angle X-ray scattering in combination with single particle analysis of transmission electron microscope images of negative-stained material we present the first three-dimensional reconstruction of non-phosphorylated RB1 revealing an extended architecture and deduce the domain arrangement within the molecule. Phosphorylation results in an overt alteration of the molecular shape and dimensions, consistent with the transition to a compact globular architecture. The work presented provides what is to our knowledge the first description of the relative domain arrangement in active RB1 and predicts the molecular movement that leads to RB1 inactivation following protein phosphorylation.

Genetics of primary intraocular tumors

Primary intraocular neoplasms are tumors that originate within the eye. The most common malignant primary intraocular tumor in adults is uveal melanoma and the second is primary intraocular lymphoma or vitreoretinal (intraocular) lymphoma. The most common malignant intraocular tumor in children is retinoblastoma. Genetics plays a vital role in the diagnosis and detection of ocular tumors. In uveal melanoma, monosomy 3 is the most common genetic alteration and somatic mutations of BAP1, a tumor suppressor gene, have been reported in nearly 50% of primary uveal melanomas. The retinoblastoma gene RB1 is the prototype tumor suppressor gene-mutations in RB1 alleles lead to inactivated RB protein and the development of retinoblastoma. Immunoglobulin heavy chain (IgH) or T-cell receptor (TCR) gene rearrangement is observed in B-cell or T-cell primary vitreoretinal lymphoma, respectively. Other factors related to the genetics of these three common malignancies in the eye are discussed and reviewed.

Retinoblastoma major review with updates on Middle East management protocols

Many advances in the field of management of retinoblastoma emerged in the past few years. Patterns of presentation of retinoblastoma in the Middle East region differ from Western community. The use of enucleation as a radical method of eradicating advanced disease is not easily accepted by patient's family. We still do see stage E, failed or resistant retinoblastoma and advanced extraocular disease ensues as a result of delayed enucleation decision. In this review, we discuss updates in management of retinoblastoma with its implication on patients in our part of the world. Identifying clinical and high risk characteristics is important prognostically and are discussed for further management of retinoblastoma cases.

Retinoblastoma - current treatment and future direction

Retinoblastoma is the commonest primary ocular malignancy of childhood. There are two forms - heritable and non heritable. Heritable retinoblastoma is a cancer susceptibility syndrome. Presentation is in the first few years of life, sometimes in the neonatal period. Early detection and prompt treatment can give cure rates up to 95% for intraocular tumours, but extraocular disease carries a very high mortality. The diagnosis is essentially clinical and biopsy is contraindicated due to the risk of extraocular spread. Treatment requires significant multidisciplinary input, with local ophthalmic treatment, systemic chemotherapy and external beam or plaque radiotherapy, or surgery to remove the affected eye. Screening of family members is essential for early detection. Lifelong surveillance of mutation carriers is needed due to the risk of second cancers. Newer treatment modalities including intra-arterial chemotherapy have been added to the therapeutic armamentarium in recent years.

Genetic profiling differentiates second primary tumors from metastases in adult metachronous soft tissue sarcoma

Purpose. Patients with soft tissue sarcomas (STS) are at increased risk of second primary malignancies, including a second STS, but distinction between metastases and a second primary STS is difficult. Patients and Methods. Array-based comparative genomic hybridization (aCGH) was applied to 30 multiple STS of the extremities and the trunk wall from 13 patients. Different histotypes were present with malignant fibrous histiocytomas/undifferentiated pleomorphic sarcomas being the predominant subtype. Results. aCGH profiling revealed genetic complexity with multiple gains and losses in all tumors. In an unsupervised hierarchical cluster analysis, similar genomic profiles and close clustering between the first and subsequent STS were identified in 5 cases, suggesting metastatic disease, whereas the tumors from the remaining 8 patients did not cluster and showed only weak pairwise correlation, suggesting development of second primary STS. Discussion. The similarities and dissimilarities identified in the first and second STS suggest that genetic profiles can be used to distinguish soft tissue metastases from second primary STS. The demonstration of genetically different soft tissue sarcomas in the same patient suggests independent tumor origin and serves as a reminder to consider development of second primary STS, which has prognostic and therapeutic implications.

[Gigantic ovarian and suprarenal cysts ten years after enucleation of unilateral retinoblastoma]

INTRODUCTION

Retinoblastoma (RB) is the most common eye tumour in children and is curable. Patients with hereditary RB have increased risk of developing additional tumours, predominantly sarcomas. The published results on the treatment of bilateral RB have shown that 10-15% of patients develop second primary tumours (SPT). Average latent period, e.g. the period from the diagnosis of bilateral RB to the appearance of SPT is 10.4 years. In the literature, the appearance of second benign tumours in patients suffering from unilateral and bilateral RB has not been analyzed separately. However, the size and the location of benign tumours can cause serious complications.

CASE OUTLINE

We present a 14-year-old female patient. At age 4 years, her left eye was enucleated owing to unilateral RB. In the postoperative period, she did not undergo irradiation, nor did she receive chemotherapy. On her regular ophthalmologic check-up, the patient informed us that her belly was "swelling" over the past four months. She had no pains or other complaints. The abdomen was significantly above the level of the chest, tense, painless on palpation, with obvious fluctuations. Abdominal echosonography confirmed the presence of a huge multilocular cystic formation, 19 x 18 cm in diameter, spreading from the pelvis to the epigastrium, and pressing the liver and spleen. A cyst of 4.7 cm in diameter was observed in the upper pole of the left kidney. Both the gigantic cyst of the left ovary (weighing 10300 g) and the left suprarenal cyst (weighing 30 g) were removed.

CONCLUSION

We report a patient who developed second non-ocular tumours (ovarian and suprarenal cysts) after successful treatment of unilateral RB. Patients treated for RB (hereditary and non-hereditary) should be checked regularly and meticulously. Early recognition of tumours, treatment can prevent possible complications.

The transglabellar/subcranial approach for surgical excision of periocular second tumors in retinoblastoma

PURPOSE

To evaluate the use of transglabellar/subcranial approach for surgical resection of periocular second non-ocular tumors in retinoblastoma patients.

METHODS

Seven retinoblastoma patients with periocular second tumor involving anterior skull base underwent surgical resection by transglabellar/subcranial approach in a single center. The medical records of these patients were retrospectively evaluated.

RESULTS

The most common presenting symptom in retinoblastoma patients with periocular second tumor was difficulty in maintaining the prosthesis in three patients (43%), followed by epistaxis in one (14%), palpable orbital mass in one (14%), persistent periocular swelling in one (14%), and visual loss in one (14%) patient. Periocular second tumors were leiomyosarcoma in three (43%) patients, osteosarcoma in three (43%), and sphenoid wing meningioma in one (14%) patient. Surgical resection by the transglabellar/subcranial approach was the only treatment in one (14%) patient with sphenoid wing meningioma and was combined with chemotherapy in three (43%) patients, and with both external beam radiotherapy and chemotherapy in three (43%) patients. Surgical margins were negative in three (43%) patients and microscopically positive in four (57%) patients. Complications were minor, including cerebral spinal fluid (CSF) leak in one (14%) patient and CSF leak and subgaleal hematoma in one (14%) patient. After 31 months mean follow-up, three (43%) patients were alive and four patients (57%) were dead.

CONCLUSIONS

Retinoblastoma patients with periocular second tumors have a poor prognosis. The transglabellar/subcranial approach can be used for surgical resection of periocular second tumor involving skull base with low morbidity.

The genome and epigenome of malignant melanoma

Malignant melanoma originates in melanocytes, the pigment-producing cells of the skin and eye, and is one of the most deadly human cancers with no effective cure for metastatic disease. Like many other cancers, melanoma has both environmental and genetic components. For more than 20 years, the melanoma genome has been subject to extensive scrutiny, which has led to the identification of several genes that contribute to melanoma genesis and progression. Three molecular pathways have been found to be nearly invariably dysregulated in melanocytic tumors, including the RAS-RAF-MEK-ERK pathway (through mutation of BRAF, NRAS or KIT), the p16 INK4A-CDK4-RB pathway (through mutation of INK4A or CDK4) and the ARF-p53 pathway (through mutation of ARF or TP53). Less frequently targeted pathways include the PI3K-AKT pathway (through mutation of NRAS, PTEN or PIK3CA) and the canonical Wnt signaling pathway (through mutation of CTNNB1 or APC). Beyond the specific and well-characterized genetic events leading to activation of proto-oncogenes or inactivation of tumor suppressor genes in these pathways, systematic high-resolution genomic analysis of melanoma specimens has revealed recurrent DNA copy number aberrations as well as perturbations of DNA methylation patterns. Melanoma provides one of the best examples of how genomic analysis can lead to a better understanding of tumor biology. We review current knowledge of the genes involved in the development of melanoma and the molecular pathways in which these genes operate.

New primary neoplasms of the central nervous system in survivors of childhood cancer: a report from the Childhood Cancer Survivor Study

BACKGROUND

Subsequent primary neoplasms of the central nervous system (CNS) have frequently been described as late events following childhood leukemia and brain tumors. However, the details of the dose-response relationships, the expression of excess risk over time, and the modifying effects of other host and treatment factors have not been well defined.

METHODS

Subsequent primary neoplasms of the CNS occurring within a cohort of 14,361 5-year survivors of childhood cancers were ascertained. Each patient was matched with four control subjects by age, sex, and time since original cancer diagnosis. Tumor site-specific radiation dosimetry was performed, and chemotherapy information was abstracted from medical records. Conditional logistic regression was used to estimate odds ratios (ORs), to calculate 95% confidence intervals (CIs), and to model the excess relative risk (ERR) as a function of radiation dose and host factors. For subsequent gliomas, standardized incidence ratios (SIRs) and excess absolute risks (EARs) were calculated based on Surveillance, Epidemiology, and End Results data.

RESULTS

Subsequent CNS primary neoplasms were identified in 116 individuals. Gliomas (n = 40) occurred a median of 9 years from original diagnosis; for meningiomas (n = 66), it was 17 years. Radiation exposure was associated with increased risk of subsequent glioma (OR = 6.78, 95% CI = 1.54 to 29.7) and meningioma (OR = 9.94, 95% CI = 2.17 to 45.6). The dose response for the excess relative risk was linear (for glioma, slope = 0.33 [95% CI = 0.07 to 1.71] per Gy, and for meningioma, slope = 1.06 [95% CI = 0.21 to 8.15] per Gy). For glioma, the ERR/Gy was highest among children exposed at less than 5 years of age. After adjustment for radiation dose, neither original cancer diagnosis nor chemotherapy was associated with risk. The overall SIR for glioma was 8.7, and the EAR was 19.3 per 10,000 person-years.

CONCLUSIONS

Exposure to radiation therapy is the most important risk factor for the development of a new CNS tumor in survivors of childhood cancers. The higher risk of subsequent glioma in children irradiated at a very young age may reflect greater susceptibility of the developing brain to radiation.

The role of cell cycle regulatory proteins in the pathogenesis of melanoma

The transformation of melanocytes to melanoma cells is characterised by abnormal proliferation resulting from alterations in cell cycle regulatory mechanisms. This occurs through alterations in the two major cell cycle regulatory pathways, the retinoblastoma (Rb) and p53 tumour suppressor pathways. This review summarises the current knowledge of alterations in these two pathways at G1/S transition and specifically the role of the key cell cycle regulatory proteins pRb, p16INK4a (p16), cyclin D1, p27Kip1 (p27), p53 and p21Waf1/Cip1 (p21) in the pathogenesis of melanoma. It also considers their prognostic significance. Current data indicate that alterations of cyclin kinase inhibitor (cdki) levels are implicated in the pathogenesis of melanoma and may be useful prognostic markers. However, large validation studies linked to comprehensive clinical follow up data are necessary to clarify the prognostic significance of cell cycle regulatory proteins in individual patients.

Outcome of secondary high-grade glioma in children previously treated for a malignant condition: A study of the Canadian Pediatric Brain Tumour Consortium

BACKGROUND AND PURPOSE

Reports of secondary high-grade glioma (HGG) in survivors of childhood cancer are scarce. The aim of this study was to review the pattern of diagnosis, the treatment, and outcome of secondary pediatric HGG.

PATIENTS AND METHODS

We performed a multi-center retrospective study among the 17 paediatric institutions participating in the Canadian Pediatric Brain Tumour Consortium (CPBTC).

RESULTS

We report on 18 patients (14 males, 4 females) treated in childhood for a primary cancer, who subsequently developed a HGG as a second malignancy. All patients had previously received radiation therapy +/- chemotherapy for either acute lymphoblastic leukaemia (n=9) or solid tumour (n=9). All HGG occurred within the previous radiation fields. At the last follow-up, 17 patients have died and the median survival time is 9.75 months.

CONCLUSION

Although aggressive treatment seems to provide sustained remissions in some patients, the optimal management is still to be defined. Further documentation of such cases is necessary in order to better understand the pathogenesis, the natural history and the prevention of these tumours.

Increased risk of malignancies in a population-based study of 818 soft-tissue sarcoma patients

Soft-tissue sarcomas (STS) have been associated with various rare cancer syndromes and occur at increased frequencies in survivors of childhood cancer. Also adult patients with STS have been suggested to be at an increased risk of additional malignancies. After exclusion of syndrome-associated and radiation-induced sarcomas, we studied multiple primary malignancies in a population-based cohort of 818 patients with primary STS of the extremities and the trunk wall. In total, 203 other malignancies developed in 164 (20%) patients median 10 (0-32) years before and median 4 (0-35) years after the sarcoma diagnosis. Standardised morbidity ratios (SMRs) were determined for primary malignancies following a STS. Hereby individuals who had developed a STS were identified to be at increased risk of second primary malignancies (SMR for all malignant tumours=1.3; 95% CI=1.0-1.5; P=0.02) with STS being the only specific tumour type that occurred at an increased risk (SMR=17.6; 95% CI=8.1-33.5; P<0.001). Hence, this population-based series demonstrates a high frequency of second primary tumours among STS patients and indicates a particularly increased risk of developing a new STS.

Application of genetic approaches to ocular disease

The human eye is a complex organ whose development requires extraordinary coordination of developmental processes. Multiple genes responsible for the proper development and maintenance of the vertebrate eye have been identified and shown to be involved in a variety of debilitating ocular conditions. Genetic diseases involving the eye represent a leading cause of blindness in children and adults. This article summarizes current genetic approaches and their application to studies of ocular disease.

Pocket protein function in melanocyte homeostasis and neoplasia

Melanoma is the most lethal of human skin cancers and its incidence is increasing worldwide [L.K. Dennis (1999). Arch. Dermatol. 135, 275; C. Garbe et al. (2000). Cancer 89, 1269]. Melanomas often metastasize early during the course of the disease and are then highly intractable to current therapeutic regimens [M.F. Demierre and G. Merlino (2004). Curr. Oncol. Rep. 6, 406]. Consequently, understanding the factors that maintain melanocyte homeostasis and prevent their neoplastic transformation into melanoma is of utmost interest from the perspective of therapeutic interdiction. This review will focus on the role of the pocket proteins (PPs), Rb1 (retinoblastoma protein), retinoblastoma-like 1 (Rbl1 also known as p107) and retinoblastoma-like 2 (Rbl2 also known as p130), in melanocyte homeostasis, with particular emphasis on their functions in the cell cycle and the DNA damage repair response. The potential mechanisms of PP deregulation in melanoma and the possibility of PP-independent pathways to melanoma development will also be considered. Finally, the role of the PP family in ultraviolet radiation (UVR)-induced melanoma and the precise contribution that each PP family member makes to melanocyte homeostasis will be discussed in the context of a number of genetically engineered mouse models.

Secondary Burkitt lymphoma in a retinoblastoma patient with 13q deletion syndrome

We report a boy with constitutional deletion 13q chromosome associated with dysmorphic features and bilateral retinoblastoma. The patient developed secondary Burkitt lymphoma 5 years after the diagnosis of retinoblastoma at the age of 8 months. He has completed treatment for both malignancies. At present, he is 7 years old and still in remission.

Melanocytes in conditional Rb-/- mice are normal in vivo but exhibit proliferation and pigmentation defects in vitro

The function of the retinoblastoma tumour suppressor (Rb1), and the pocket protein family in general, has been implicated as an important focal point for deregulation in many of the molecular pathways mutated in melanoma. We have focused on the role of Rb1 in mouse melanocyte homeostasis using gene targeting and Cre/loxP mediated tissue-specific deletion. We show that constitutive Cre-mediated ablation of Rb1 exon 2 prevents the production of Rb1 and recapitulates the phenotype encountered in other Rb1 knockout mouse models. Mice with conditional melanocyte-specific ablation of Rb1 manifest overtly normal pigmentation and are bereft of melanocytic hyperproliferative defects or apoptosis-induced depigmentation. Histologically, these mice have melanocyte morphology and distribution comparable with control littermates. In contrast, Rb1-null melanocytes removed from their in vivo micro-environment and cultured in vitro display some of the characteristics associated with a transformed phenotype. They proliferate at a heightened rate when compared with control melanocytes and have a decreased requirement for mitogens. With progressive culture the cells depigment at relatively early passage and display a gross morphology which, whilst reminiscent of early passage melanocytes, is generally different to equivalent passage control cells. These results indicate that Rb1 is dispensable for in vivo melanocyte homeostasis when its ablation is targeted from the melanoblast stage onwards, however, when cultured in vitro, Rb1 loss increases melanocyte growth but the cells are not fully transformed.