NOTE The report of the Committee without its annexes appears as Official Records of the General Assembly, Sixty-third Session, Supplement No. 46. The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The country names used in this document are, in most cases, those that were in use at the time the data were collected or the text prepared. In other cases, however, the names have been updated, where this was possible and appropriate, to reflect political changes. Scientific Annexes Annex A. Medical radiation exposures Annex B. Exposures of the public and workers from various sources of radiation INTROdUCTION 1. In the course of the research and development for and the application of atomic energy and nuclear technologies, a number of radiation accidents have occurred. Some of these accidents have resulted in significant health effects and occasionally in fatal outcomes. The application of technologies that make use of radiation is increasingly widespread around the world. Millions of people have occupations related to the use of radiation, and hundreds of millions of individuals benefit from these uses. Facilities using intense radiation sources for energy production and for purposes such as radiotherapy, sterilization of products, preservation of foodstuffs and gamma radiography require special care in the design and operation of equipment to avoid radiation injury to workers or to the public. Experience has shown that such technology is generally used safely, but on occasion controls have been circumvented and serious radiation accidents have ensued. 2. Reviews of radiation exposures from accidents have been presented in previous UNSCEAR reports. The last report containing an exclusive chapter on exposures from accidents was the UNSCEAR 1993 Report [U6]. 3. This annex is aimed at providing a sound basis for conclusions regarding the number of significant radiation accidents that have occurred, the corresponding levels of radiation exposures and numbers of deaths and injuries, and the general trends for various practices. Its conclusions are to be seen in the context of the Committee's overall evaluations of the levels and effects of exposure to ionizing radiation. 4. The Committee's evaluations of public, occupational and medical diagnostic exposures are mostly concerned with chronic exposures of …

sources and effects of ionizing radiation

The retinoblastoma gene was identified over a decade ago as the first tumor suppressor. Although the gene was initially cloned as a result of its frequent mutation in the rare pediatric eye tumor, retinoblastoma (Friend et al. 1986; Fung et al. 1987; Lee et al. 1987), it is now thought to play a fundamental role in cellular regulation and is the target of tumorigenic mutations in many cell types. The retinoblastoma gene encodes a 928–amino acid phosphoprotein, Rb, which arrests cells in the G1 phase (Weinberg 1995). Rb is phosphorylated and dephosphorylated during the cell cycle; the hyperphosphorylated (inactive) form predominates in proliferating cells, whereas the hypophosphorylated (active) form is generally more abundant in quiescent or differentiating cells (Chen et al. 1989). As a demonstration its tumor suppressor activity, Rb was reintroduced into Rb-deficient tumor cells and it blocked several features of the malignant phenotype (Huang et al. 1988). Mutations affecting the retinoblastoma gene are frequently encountered, not only in retinoblastoma but also in other cancers such as osteosarcoma, small cell lung cancer, prostate cancer, and breast cancer (Friend et al. 1986; Fung et al. 1987; Harbour et al. 1988; Lee et al. 1988; T’Ang et al. 1988; Bookstein et al. 1990). Indeed, children with hereditary retinoblastoma have 30-fold increased risk of developing a second, nonocular malignancy, especially bone and soft tissue sarcomas in adolescence and cutaneous melanomas in adulthood (Eng et al. 1993; Moll et al. 1997). These second neoplasms occur almost exclusively in patients who have germ-line mutations in the retinoblastoma gene. As a further indication of its fundamental role in tumor suppression, Rb can be functionally inactivated by constitutive hyperphosphorylation in tumors that do not have mutations in the retinoblastoma gene (Sherr 1996). In addition, DNA tumor viruses express oncoproteins, such as adenovirus E1A, SV40 large tumor antigen, and human papillomavirus (HPV) E7, that bind and inactivate Rb; these proteins are required for the viruses to transform cells (DeCaprio et al. 1988; Whyte et al. 1988; Dyson et al. 1989). Rb function depends, at least in part, on interactions with the E2F family of DNA-binding transcription factors (E2F) (Chellappan et al. 1991; Dyson 1998; Nevins 1998). E2F sites are found in the promoters of many genes that are important for cell cycle progression, and Rb appears to repress transcription of these genes through its interaction with E2F (Blake and Azizkhan 1989; Thalmeier et al. 1989; Dalton 1992; Ohtani et al. 1995). Recent findings in the Rb/E2F field are clarifying how this pathway regulates the transition from G1 to S phase at the molecular level. Other emerging results show that this pathway also regulates other parts of the cell cycle and that it may even have roles beyond cell cycle control. In this article, we review the current understanding of the mechanism of action of Rb and its roles in cell cycle regulation, apoptosis, and development. We refer readers to recent reviews by Bartek et al. (1997), Dyson (1998), Lipinski and Jacks (1999), and Sherr and Roberts (1999) for additional in-depth analysis of the field and for historical perspectives.

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The Rb/E2F pathway: expanding roles and emerging paradigms

In this meta-analytic and narrative review, we examine several overarching issues related to the study of coping, emotion regulation, and internalizing and externalizing symptoms of psychopathology in childhood and adolescence, including the conceptualization and measurement of these constructs. We report a quantitative meta-analysis of 212 studies (N = 80,850 participants) that measured the associations between coping and emotion regulation with symptoms of internalizing and externalizing psychopathology. Within the meta-analysis we address the association of broad domains of coping and emotion regulation (e.g., total coping, emotion regulation), intermediate factors of coping and emotion regulation (e.g., primary control coping, secondary control coping), and specific coping and emotion regulation strategies (e.g., emotional expression, cognitive reappraisal) with internalizing and externalizing symptoms. For cross-sectional studies, which made up the majority of studies included, we examine 3 potential moderators: age, measure quality, and single versus multiple informants. Finally, we separately consider findings from longitudinal studies as these provide stronger tests of the effects. After accounting for publication bias, findings indicate that the broad domain of emotion regulation and adaptive coping and the factors of primary control coping and secondary control coping are related to lower levels of symptoms of psychopathology. Further, the domain of maladaptive coping, the factor of disengagement coping, and the strategies of emotional suppression, avoidance, and denial are related to higher levels of symptoms of psychopathology. Finally, we offer a critique of the current state of the field and outline an agenda for future research. (PsycINFO Database Record

Coping, emotion regulation, and psychopathology in childhood and adolescence: A meta-analysis and narrative review

Four decades have passed since the first discovery of collagen IV by Kefalides in 1966. Since then collagen IV has been investigated extensively by a large number of research laboratories around the world. Advances in molecular genetics have resulted in identification of six evolutionary related mammalian genes encoding six different polypeptide chains of collagen IV. The genes are differentially expressed during the embryonic development, providing different tissues with specific collagen IV networks each having unique biochemical properties. Newly translated α-chains interact and assemble in the endoplasmic reticulum in a chain-specific fashion and form unique heterotrimers. Unlike most collagens, type IV collagen is an exclusive member of the basement membranes and through a complex inter- and intramolecular interactions form supramolecular networks that influence cell adhesion, migration, and differentiation. Collagen IV is directly involved in a number of genetic and acquired disease such as Alport's and Goodpasture's syndromes. Recent discoveries have also highlighted a new and direct role for collagen IV in the development of rare genetic diseases such as cerebral hemorrhage and porencephaly in infants and hemorrhagic stroke in adults. Years of intensive investigations have resulted in a vast body of information about the structure, function, and biology of collagen IV. In this review article, we will summarize essential findings on the structural and functional relationships of different collagen IV chains and their roles in health and disease.

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Mammalian collagen IV.

Context. —There is a substantial risk of a second cancer for persons with hereditary retinoblastoma, which is enhanced by radiotherapy. Objective. —To examine long-term risk of new primary cancers in survivors of childhood retinoblastoma and quantify the role of radiotherapy in sarcoma development. Design. —Cohort incidence study of patients with retinoblastoma followed for a median of 20 years, and nested case-control study of a radiation dose-response relationship for bone and soft tissue sarcomas. Setting/Participants. —A total of 1604 patients with retinoblastoma who survived at least 1 year after diagnosis, identified from hospital records in Massachusetts and New York during 1914 to 1984. Results. —Incidence of subsequent cancers was statistically significantly elevated only in the 961 patients with hereditary retinoblastoma, in whom 190 cancers were diagnosed, vs 6.3 expected in the general population (relative risk [RR], 30 [95% confidence interval, 26-47]). Cumulative incidence (±SE) of a second cancer at 50 years after diagnosis was 51.0% (±6.2%) for hereditary retinoblastoma, and 5.0% (±3.0%) for nonhereditary retinoblastoma. All 114 sarcomas of diverse histologic types occurred in patients with hereditary retinoblastoma. For soft tissue sarcomas, the RRs showed a stepwise increase at all dose categories, and were statistically significant at 10 to 29.9 Gy and 30 to 59.9 Gy. A radiation risk for all sarcomas combined was evident at doses above 5 Gy, rising to 10.7-fold at doses of 60 Gy or greater ( P Conclusions.— Genetic predisposition has a substantial impact on risk of subsequent cancers in retinoblastoma patients, which is further increased by radiation treatment. A radiation dose-response relationship is demonstrated for all sarcomas and, for the first time in humans, for soft tissue sarcomas. Retinoblastoma patients should be examined for new cancers and followed into later life to determine whether their extraordinary cancer risk extends to common cancers of adulthood.

https://jamanetwork.com/HttpHandlers/ArticlePdfHandler.ashx?journal=JAMA&articleId=418394&pdfFileName=jama_278_15_037.pdf

Cancer Incidence After Retinoblastoma: Radiation Dose and Sarcoma Risk

Incidence of retinoblastoma in children born after in-vitro fertilisation.

Background: Survivors of hereditary retinoblastoma have an elevated risk of developing second malignancies, but data on the risk in middle-aged retinoblastoma survivors (ie, those with more than 40 years of follow-up) are scarce. Methods: Data from the Dutch retinoblastoma registry were used to analyze risks of second malignancies in 668 retinoblastoma survivors, diagnosed from 1945 to 2005 (median age = 24.9 years) and classified as having had hereditary or nonhereditary disease based on the presence of family history, bilateral disease, or a germline RB1 mutation. Standardized incidence ratios (SIRs) and absolute excess risks (AERs) of subsequent cancers in patients with hereditary and nonhereditary disease were estimated by comparison with Dutch sex-, age-, and calendar year-specific rates. Multivariable Cox regression and competing risk analyses were used to determine associations of treatment with risks of second malignancies. All statistical tests were two-sided. Results: After a median follow-up of 21.9 years, the risk of second malignancies in survivors of hereditary retinoblastoma (SIR = 20.4, 95% confidence interval [CI] = 15.6 to 26.1) far exceeded the risk of survivors of nonhereditary retinoblastoma (SIR = 1.86, 95% CI = 0.96 to 3.24). Among patients with hereditary disease, treatment with radiotherapy was associated with a further increase in the risk of a subsequent cancer (hazard ratio = 2.81, 95% CI = 1.28 to 6.19). After 30 years of follow-up, elevated risks of epithelial cancers (lung, bladder, and breast) were observed among survivors of hereditary retinoblastoma. After 40 years of follow-up, the AER of a second malignancy among survivors of hereditary retinoblastoma had increased to 26.1 excess cases per 1000 person-years. The cumulative incidence of any second malignancy 40 years after retinoblastoma diagnosis was 28.0% (95% CI = 21.0% to 35.0%) for patients with hereditary disease. Conclusion: Our analysis of middle-aged hereditary retinoblastoma survivors suggests that these individuals have an excess risk of epithelial cancer. Lifelong follow-up studies are needed to evaluate the full spectrum of subsequent cancer risk in hereditary retinoblastoma survivors. © The Author 2008. Published by Oxford University Press.

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Risk of Second Malignancies in Survivors of Retinoblastoma: More Than 40 Years of Follow-up

Second primary tumors in hereditary retinoblastoma: a register-based study, 1945-1997: is there an age effect on radiation-related risk?

AIM—The aim of this study was to determine the (time trends in) incidence and survival of hereditary (familial and sporadic) and non-hereditary retinoblastoma for male and female patients born in the Netherlands between 1862 and 1995.
METHOD—The national retinoblastoma register was updated and now consists of 955 patients. The missing dates of death were obtained from the municipal registers and the Central Bureau of Genealogy in The Hague. Mortality was compared with the Dutch vital statistics.
RESULTS—From 1862 to 1995 no significant differences in incidence for retinoblastoma were found in the hereditary subgroups. Further, no significant differences between males and females were found, both overall and in the hereditary subgroups. The average incidence of retinoblastoma increased untill 1944, probably due to incompleteness of the register, and stabilised after 1945 (1 per 17 000 live births). From 1900 to 1995 the standardised mortality ratio increased for hereditary retinoblastoma patients from 2.9 to 9.0 and decreased for non-hereditary retinoblastoma patients from 1.9 to 1.0.
CONCLUSION—Although survival for retinoblastoma was significantly better after 1945 than before, in comparison with the Dutch population the mortality between 1900 and 1990 increased for the hereditary and decreased for the non-hereditary retinoblastoma patients.

https://bjo.bmj.com/content/bjophthalmol/81/7/559.full.pdf

Incidence and survival of retinoblastoma in The Netherlands: a register based study 1862-1995.

Purpose: The aim of this survey was to review the different studies regarding the occurrence of second primary tumors (SPT) among survivors of retinoblastoma. Methods: Ovid (Medline, Current contents life, Psychlit, Embase) was searched for the years 1966 - 1995 using the mesh headings: ‘retinoblastoma’, ‘second primary neoplasms’, and ‘multiple primary neoplasms’. The inclusion criteria were: the study should involve 50 patients or more and should not be limited to one specific SPT. A checklist with criteria regarding the study design and the results was applied to each study. Results: Eleven studies were identified which met the inclusion criteria. Thirty-five different types of SPT (Ntotal =243) were reported. Most of them were osteosarcomas (37.0%), followed by melanomas (74%), soft-tissue sarcomas (6.9%), brain tumors (4.5%), fibrosarcomas (3.3%), chondrosarcomas (3.3%), and sarcomas (3.3%). Less frequently reported were leukemias (2.4%), sebaceous cell carcinomas (1.6%), and non-Hodgkin lymphomas (1...

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Saskia M. Imhof

Papers

Incidence of retinoblastoma in children born after in-vitro fertilisation.

Risk of Second Malignancies in Survivors of Retinoblastoma: More Than 40 Years of Follow-up

Second primary tumors in hereditary retinoblastoma: a register-based study, 1945-1997: is there an age effect on radiation-related risk?

Incidence and survival of retinoblastoma in The Netherlands: a register based study 1862-1995.

Second primary tumors in patients with retinoblastoma: a review of the literature