Risk of cancer among offspring of childhood-cancer survivors. Association of the Nordic Cancer Registries and the Nordic Society of Paediatric Haematology and Oncology

Perinatal and childhood outcomes of children born to female cancer survivors in South Korea

Despite the increasing number of female cancer survivors, uncertainty remains regarding potential adverse health outcomes for their offspring. Comprehensive population-based studies would be invaluable for female cancer survivors in making decisions about their future. This study uses the National Health Information Database to investigate perinatal and long-term outcomes of offspring born to mothers with a history of cancer. In a South Korean cohort of 95,264 women aged 15-40 diagnosed with cancer between 2007 and 2010, we evaluated the outcomes of 15,221 children born to 11,092, cancer survivors. We selected 147,727 women without a history of cancer and 201,444 children as a control group. Our study found that children of female cancer survivors have a significantly higher odds ratio of primary outcomes including preterm birth, low birth weight, neonatal intensive care unit admission, and death. While there was no difference in the rate of death within 1 year of birth between the two groups, the total death rate during the follow-up period was significantly higher in children born to mothers with cancer. After adjusting for gestational age and birth weight, there was no statistically significant increased hazard ratio of secondary outcomes including cancer, chromosomal abnormalities, cerebral palsy, delayed development, epilepsy, language disorder, or hearing impairment.

Parenthood for childhood cancer survivors: unfounded fear of cancer development in offspring and related health behaviors

Current literature reveals no increased risk for adverse non-hereditary health outcomes in the offspring of childhood cancer survivors (CCS), yet survivors reported concerns regarding their offspring's health. To investigate how the fear of cancer development in offspring influences parental behavior related to health and prevention, survey reports from 256 European adult CCS and 256 age- and sex-matched siblings who participated in a multicenter study on offspring health were analyzed in the present study. Analyses of covariance and chi-square tests were conducted to test for differences between CCS and siblings in outcome variables (all related to healthy parenting behavior). CCS reported higher fear levels (p = 0.044, Partial η2 = 0.01) and less alcohol consumption (p = 0.011, Phi = 0.12) and smoking (p = 0.022, Phi = 0.11) during pregnancy than siblings. In survivor families, children were breastfed less often (p < 0.001, Phi = 0.18). Partial correlation analyses showed that CCS' fear levels decreased with increasing age (r = -0.16, p = 0.014), time since oncological therapy (r = -0.19, p = 0.003), and number of children (r = -0.21, p = 0.001). Overall, due to their own experiences with cancer, many CCS harbor misperceptions regarding the health outcomes of their offspring. Although the fear decreases with increasing distance from the active disease, any fear should be taken seriously, even if unfounded, and combated through targeted educational measures.

Long-Term Morbidity and Mortality in Children After In Utero Exposure to Maternal Cancer

PURPOSE

In utero exposure to maternal cancer and cancer treatment might influence the child's short- and long-term health and development. The objective of the study was to investigate short- and long-term somatic and psychiatric outcomes in children exposed to maternal cancer in utero.

METHODS

This nationwide cohort study identified all liveborn children in Denmark between January 1978 and December 2018. Exposure was defined as maternal cancer diagnosis during pregnancy, and in a subgroup analysis, exposure to chemotherapy in utero. The main outcomes of interest were overall mortality, somatic diagnoses, and psychiatric diagnoses identified in the National Health Registers. Follow-up started at birth and ended at an event, death, emigration, or end of 2018. Hazard ratios of end points adjusted for potential confounders were estimated using Cox regression analysis.

RESULTS

Of 2,526,163 included liveborn children, 690 (0.03%) were exposed to maternal cancer in utero. Compared with unexposed fetuses, children exposed in utero had no higher overall mortality, adjusted hazard ratio 0.8 (95% CI, 0.4 to 1.5), nor increased risk of congenital malformations, overall somatic or psychiatric disease. During the period 2002-2018, of 378 (0.03%) children exposed to cancer in utero, 42 (12.5%) were exposed to chemotherapy. Among these 42 children, in utero exposure to chemotherapy was not associated with selected somatic diseases nor to congenital malformations when compared with in utero exposure to maternal cancer without chemotherapy.

CONCLUSION

Overall, findings did not indicate excess risk of mortality or severe morbidity among children exposed to cancer in utero. Fetal exposure to chemotherapy was not associated with adverse health outcomes in childhood.

The Outcome of Fatherhood in Patients With Philadelphia-Negative Myeloproliferative Neoplasms: A Single-Institution Experience

Background

Fertility is a highly complex subject; it involves more than one individual and has profound psychological and economic implications. Moreover, it is affected by several factors, including age, significant systemic illness in either partner, exposure to environmental toxins, medications, or radiation. In patients with malignancy, fertility is more complicated. Patients with a malignancy might have reduced fertility due to the disease, medication, and radiation. Besides the reduced fertility, there are more concerns regarding the subsequent effect of cancer treatment on their offspring and the possibility of having healthy children. There were many studies regarding fertility in patients with cancer; however, in male patients with Philadelphia-negative myeloproliferative neoplasms (MPNs), there are very limited data.

Objectives

In this study, we aim to see the outcome of fatherhood in male patients with Philadelphia-negative myeloproliferative neoplasms (MPNs), polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) whether on treatment or not.

Methods

A retrospective mixed-design study of male patients with Philadelphia-negative MPN was followed up in our institute (National Center for Cancer Care and Research (NCCCR)), Doha, Qatar, between January 1, 2008, and January 1, 2020. Patients were interviewed regarding fertility-related information. All included patients had a confirmed diagnosis of Philadelphia-negative MPN according to World Health Organization (WHO) 2008 or WHO 2016 criteria for MPN, aged more than 18 years old.

Results

A total of 124 male patients were interviewed, and only 20 patients met the inclusion criteria. The majority of the patients were lost to follow-up or could not be contacted, and 28.8% of the excluded patients had their families completed by the time of diagnosis. The treatment received included hydroxycarbamide (n=8), pegylated interferon 2 alpha (n=10), ruxolitinib (n=1), and phlebotomy (n=1). The mean duration of exposure to treatment before pregnancy was 4.7 years. The mode of delivery was normal vaginal delivery in 71.4% of the pregnancies. The total number of offspring was 30, and the total number of conceptions was 30.

Conclusion

Our data showed that most Philadelphia-negative MPN male patients on treatment had their offspring born normally with no serious complications, congenital anomalies, or reports of MPN-related cancers. Patients’ concerns regarding fertility should be addressed well to ensure a better quality of life.

Health of children born to childhood cancer survivors: Participant characteristics and methods of the Multicenter Offspring Study

INTRODUCTION

Research on childhood cancer survivor offspring has been limited to genetic disease occurrence, malformations or non-hereditary cancers. However, previous surveys indicated that survivors harbor fears about their (prospective) children's overall health. Our Multicenter Offspring Study examined extensive health aspects in children born to survivors and their siblings providing comprehensive information to be used in patient counseling to elucidate and alleviate existing concerns.

METHODS

Using a specifically designed questionnaire, childhood cancer survivors and their siblings were surveyed on their offspring's health (Supplementary material). Recruitment strategies depended on local infrastructures and standards of participating centers, including registry-based and direct approaches. Group differences were tested non-parametrically and effect sizes were calculated.

RESULTS

In total, 1126 survivors reported on 1780 offspring and 271 siblings reported on 441 offspring. Response rates ranged from 32.1% (Czech Republic) to 85.0% (Austria). Respondents were more likely to be female (p = .007), older at time of survey (p < .001), diagnosed 1980-1999 (p < .001) and treated with chemotherapy (p < .001). Compared to siblings, survivors were younger at time of survey (35 years vs. 39 years, p < .001) and at first birth (29 years vs. 30 years, p < .001). Survivor and sibling offspring only differed in terms of age at survey (6.3 years vs. 8.9 years, p < .001).

CONCLUSION

The Multicenter Offspring Study investigates a wide variety of health aspects in offspring born to survivors and their siblings in five European countries. Our study cohorts form a solid basis for future analyses; yet, certain limitations, due to differences in approach among participating centers, must be considered when interpreting findings.

Risk of induced abortions in childhood cancer survivors

BACKGROUND

The relative probability of pregnancy and parenthood in cancer survivors is reduced. Studies have shown that cancer survivors are concerned about the health of their offspring and the recurrence of their own cancer. This could lead to an increased risk of induced abortion. The aim of this study was to examine whether pregnancies of childhood cancer survivors (CCSs) who were 0 to 14 years old at diagnosis in 1971-2012 were more likely to result in induced abortions in comparison with population controls.

METHODS

Data from Finnish registries for cancer, births, and induced abortions were merged to identify 420 first pregnancies of CCSs and 2508 first pregnancies of age-matched population controls in 1987-2013. Poisson regression and logistic regression modeling were used to estimate incidence rates and relative risks (RRs) with 95% confidence intervals (CIs) of first pregnancies and induced abortions in CCSs in comparison with population controls.

RESULTS

The risk of first pregnancy was reduced in CCSs in comparison with population controls (RR, 0.72; 95% CI, 0.64-0.80), whereas the risk of a first pregnancy resulting in an induced abortion was similar in CCSs and population controls (RR, 1.01; 95% CI, 0.77-1.33). In subanalyses stratifying by decade of diagnosis and cancer treatment, the risk of induced abortion was similar in CCSs and population controls.

CONCLUSIONS

Female CCSs do not have an overall increased risk of induced abortions. The reduced probability of pregnancy among CCSs highlights the continued need for interventions to preserve fertility at the time of a cancer diagnosis.

Reproductive intentions in childless female adolescent and young adult cancer survivors

OBJECTIVE

To examine the association between prior cancer treatments, medical comorbidities, and voluntary childlessness in reproductive-age women who are survivors of cancers diagnosed as adolescents and young adults (AYA survivors).

DESIGN

Cross-sectional analysis.

SETTING

Participants were recruited from California and Texas cancer registries, fertility preservation programs, and cancer advocacy groups.

PATIENT(S)

Women (n = 413) ages 18-40 who were diagnosed with cancer between ages 15 and 35, completed primary cancer treatments, had at least one ovary, and were nulliparous.

INTERVENTION(S)

Cancer treatment gonadotoxicity and medical comorbidities.

MAIN OUTCOME MEASURE(S)

Voluntary childlessness.

RESULT(S)

The mean age of survivors was 31.8 years (SD, 4.9) with a mean of 6.5 years (SD, 4.4) since cancer diagnosis. Breast (26%), thyroid (19%), and Hodgkin lymphoma (18%) were the most common cancers. Twenty-two percent of the cohort was voluntarily childless. Medical comorbidities, cancer diagnosis, prior surgery, prior chemotherapy, and prior gonadotoxic treatments were not significantly associated with voluntary childlessness. In adjusted analysis, survivors of older reproductive age (adjusted odds ratio = 2.97 [1.71-5.18]) and nonheterosexual participants (adjusted odds ratio = 4.71 [2.15-10.32]) were more likely to report voluntary childlessness.

CONCLUSION(S)

A moderate proportion of AYA cancer survivors are voluntarily childless, but reproductive intentions were not related to cancer type or cancer treatments. AYA survivors of older age and nonheterosexual identification were more likely to be voluntarily childless. These data support assessing reproductive intentions and tailoring reproductive care such as fertility and contraception counseling that is appropriate for a survivor's intentions.

Linking population-based registries to identify familial cancer risk in childhood cancer

BACKGROUND

Linked population-based registries provide a unique source for identification of new family cancer syndromes and for elucidating risk of early-onset cancer in close relatives of cancer patients.

METHODS

Using the Finnish Cancer Registry, we identified 9078 probands who had been diagnosed with cancer at <21 years of age between 1970 and 2012. Siblings, offspring, parents, nephews, and nieces of probands were identified from the Population Registry. Childhood and young adult (ChYA) cancer diagnoses (age 0-39 years) in relatives were identified by linking to the Finnish Cancer Registry. The relative risk of ChYA cancer in family members of probands was estimated using standardized incidence ratios (SIRs).

RESULTS

Among 58,010 family members of the 9078 probands, 363 ChYA cancers were diagnosed, 324 of which were expected (SIR, 1.12; 95% CI, 1.01-1.24). The risk of ChYA cancer was elevated both in offspring (SIR, 2.25; 95% CI, 1.51-3.24) and in siblings (SIR, 1.17; 95% CI, 1.01-1.36). Offspring of probands with retinoblastoma were at highest risk (SIR, 75.85; 95% CI, 32.75-149.45); risks were also elevated for siblings of probands with lymphoma (SIR, 1.62; 95% CI, 1.14-2.25). Known cancer predisposition syndromes were observed in 29 (66%) of 44 sibling pairs with cancers diagnosed at <21 years of age and in 20% of the 135 families with a childhood cancer proband whose sibling was diagnosed with a young adult malignancy.

CONCLUSION

Linked population-based registry data indicate a modestly increased risk of ChYA in relatives of children with cancer. Some of the observed cancer clusters in the cohort suggest novel patterns and familial cancer syndromes.

Genetics-related service and information needs of childhood cancer survivors and parents: a mixed-methods study

Genetics in paediatric oncology is becoming increasingly important in diagnostics, treatment and follow-up care. Genetic testing may offer a possibility to stratify survivors follow-up care. However, survivors' and parents' preferences and needs for genetics-related services are largely unknown. This mixed-methods study assessed genetics-related information and service needs of survivors and parents. Six hundred and twenty-two participants (404 survivors: mean age: 26.27 years; 218 parents of survivors: mean age of child: 13.05 years) completed questionnaires. Eighty-seven participants (52 survivors; 35 parents) also completed in-depth telephone interviews. We analysed data using multivariable logistic regression and qualitative thematic analyses. Thirty-six of 50 families who were offered cancer-related genetic testing chose to undergo testing. Of those not offered testing, 11% of survivors and 7.6% of parents indicated that they believed it was 'likely/very likely' that the survivor had inherited a gene fault. Twenty-nine percent of survivors and 36% of parents endorsed access to a genetics specialist as important in their care. Survivors (40.9%) and parents (43.7%) indicated an unmet need for information about genetics and childhood cancer. Parents indicated a higher unmet need for information related to the survivors' future offspring than survivors (p < 0.001). Many survivors and parents have unmet needs for genetics-related services and information. Greater access to services and information might allow survivors at high risk for late effects to detect and prevent side effects early and improve medical outcomes. Addressing families' needs and preferences during survivorship may increase satisfaction with survivorship care.

Radiations and female fertility

Hundreds of thousands of young women are diagnosed with cancer each year, and due to recent advances in screening programs, diagnostic methods and treatment options, survival rates have significantly improved. Radiation therapy plays an important role in cancer treatment and in some cases it constitutes the first therapy proposed to the patient. However, ionizing radiations have a gonadotoxic action with long-term effects that include ovarian insufficiency, pubertal arrest and subsequent infertility. Cranial irradiation may lead to disruption of the hypothalamic-pituitary-gonadal axis, with consequent dysregulation of the normal hormonal secretion. The uterus might be damaged by radiotherapy, as well. In fact, exposure to radiation during childhood leads to altered uterine vascularization, decreased uterine volume and elasticity, myometrial fibrosis and necrosis, endometrial atrophy and insufficiency. As radiations have a relevant impact on reproductive potential, fertility preservation procedures should be carried out before and/or during anticancer treatments. Fertility preservation strategies have been employed for some years now and have recently been diversified thanks to advances in reproductive biology. Aim of this paper is to give an overview of the various effects of radiotherapy on female reproductive function and to describe the current fertility preservation options.

Best Practices in Counseling Young Female Cancer Survivors on Reproductive Health

In the United States, there are more than 400,000 girls and young women of reproductive-age with a history of cancer. Cancer treatments including surgery, chemotherapy, targeted therapy, and radiation can adversely impact their reproductive health. This review discusses infertility, contraception, and adverse pregnancy and child health outcomes in reproductive-aged cancer survivors, to increase awareness of these health risks for survivors and their health care providers. Infertility rates are modestly higher, while rates of using contraception and using highly effective contraceptive methods are lower in cancer survivors than in women without a history of cancer. During pregnancy, preterm births are also more common in survivors, resulting in more low-birth-weight offspring. Children of cancer survivors do not have more childhood cancers, birth defects, or chromosomal abnormalities than the general population, with the exception of families with hereditary cancer. Reproductive risks in survivors depend on cancer treatment exposures. For example, women with prior abdominal or pelvic radiation have additional risks of spontaneous abortions, small-for-gestational-age offspring and stillbirths, while those with prior chest radiation or anthracycline exposures have higher risks of cardiomyopathy. To help survivors achieve their reproductive goals safely, family planning and preconception counseling are central to survivorship care.

Pregnancy and child health outcomes in pediatric and young adult leukemia and lymphoma survivors: a systematic review

As long-term survival is high for children and young adults diagnosed with leukemia and lymphoma, delineating maternal, fetal and offspring health risks is important to their family planning. This systematic review examined data comparing these health risks between leukemia and lymphoma survivors and women without a history of cancer. Following a search of Embase, PubMed, CINAHL, Cochrane, and Web of Science, 142 articles were screened and 18 were included in this review. No higher risks of spontaneous abortion, maternal diabetes and anemia, stillbirth, birth defects, or childhood cancer in offspring were observed in survivors compared to controls. Important to counseling and clinical care, live birth rates were lower, while preterm birth and low birth weight risks were modestly higher in survivors compared to controls. Findings were largely reassuring but highlight the lack of data on maternal cardiopulmonary risks, differential risk by cancer treatment type, and interventions to decrease these risks.

Genetic Effect of Chemotherapy Exposure in Children of Testicular Cancer Survivors

PURPOSE

Cancer survivors express anxiety that chemotherapy exposure may lead to transmissible genetic damage in posttreatment children. Preclinical models suggest that chemotherapy exposure may result in considerable genomic alterations in postexposure progeny. Epidemiologic studies have not demonstrated a significant increase in congenital abnormalities in posttreatment children of cancer survivors, but the inherited genome-wide effect of chemotherapy exposure in humans is unknown.

EXPERIMENTAL DESIGN

Two testicular cancer survivors cured with chemotherapy who had children pre- and postexposure without sperm banking were identified. Familial germline whole genome sequencing (WGS) was performed for these families, and analytic methods were utilized to identify de novo alterations, including mutations, recombinations, and structural rearrangements in the pre- and postexposure offspring.

RESULTS

No increase in de novo germline mutations in postexposure children compared with their preexposure siblings was found. Furthermore, there were no increased short insertion/deletions, recombination frequency, or structural rearrangements in these postexposure children.

CONCLUSIONS

In two families of male cancer survivors, there was no transmissible genomic impact of significant mutagenic exposure in postexposure children. This study may provide possible reassuring evidence for patients undergoing chemotherapy who are unable to have pretreatment sperm cryopreservation. Expanded cohorts that utilize WGS to identify environmental exposure effects on the inherited genome may inform the generalizability of these results. Clin Cancer Res; 22(9); 2183-9. ©2015 AACR.

Management of acute myeloid leukemia during pregnancy

Diagnosis of acute leukemia during pregnancy presents significant medical challenges. Pancytopenia, caused by bone marrow substitution with leukemic cells, impairs maternal and fetal health. Chemotherapeutic agents required to be immediately used to save the mother's life are likely to adversely affect fetal development and outcome, especially if administered at an early gestational stage. Patients diagnosed with acute leukemia during the first trimester are, therefore, recommended to undergo pregnancy termination. At later gestational stages, antileukemic therapy can be administered, although in this case, fetal outcome is still associated with increased incidence of growth restriction and loss. Special attention to the issue of future reproduction, adopting a personalized fertility preservation approach, is required. This article addresses these subjects, presenting women diagnosed with acute myeloid and acute promyelocytic leukemia in pregnancy. The rarity of this event, resulting in insufficient data, emphasizes the need for collaborative efforts to optimize management of this complicated clinical condition.

Counseling women and men regarding exposures to reproductive and developmental toxicants before conception or women during pregnancy

It should be apparent that determining the reproductive risks of an exposure during pregnancy or the cause of a child's congenital malformations is not a simple process. It involves a careful analysis of the medical and scientific literature pertaining to the reproductive toxic effects of exogenous agents in humans and animals, as well as an evaluation of the exposure and the biological plausibility of the concern of an increased risk or a causal connection between the exposure and a child's congenital malformations. It also involves having available a detailed physical examination of the malformed infant or child and a review of the scientific literature pertaining to genetic and environmental causes of the malformations in question. Abridged counseling on the basis of superficial and incomplete analyses is a disservice to the family. Experienced counselors understand that their primary task is to educate the pregnant women or family members concerning the risk of an environmental exposure. The counselor should advise them on the options available, but not on which option to select.

A 10-year follow up of reproductive function in women treated for childhood cancer

Previously, this study group found that female childhood cancer survivors could be at risk of early cessation of fertility. The aim of the present study was to evaluate reproductive function in the same group of survivors 10 years after the initial study. Of the original cohort of 100, 71 were re-examined. Thirty-six survivors reported regular menstrual cycles. When they were compared with 210 controls, they differed significantly in antral follicle count (AFC) (median 15 versus 18, P=0.047) but not in anti-Müllerian hormone (AMH) (median 13.0 versus 17.8 pmol/l). Survivors cured with minimal gonadotoxic treatment had significantly higher AMH and AFC compared with survivors cured with either potentially gonadotoxic treatment or treatment including alkylating chemotherapy and ovarian irradiation (20.0, 5.8 and <3 pmol/l, P<0.001; and 15, 9 and 2, P=0.03, respectively). Thirty-eight survivors had achieved at least one live birth. Complicated second-trimester abortions (n=4) were observed primarily in survivors cured with radiotherapy affecting pelvic organs. In conclusion, childhood cancer survivors have signs of diminished ovarian reserve. However, if the ovarian function is preserved in the early to mid-twenties, it is likely to persist until the mid-thirties, giving a good chance of childbearing.

Maternal and neonatal outcomes in pregnancies following colorectal cancer

BACKGROUND

The risks of adverse obstetric outcomes among young women survivors of colorectal cancer (CRC) are uncertain.

METHODS

This Western Australian, whole-jurisdictional linked-data, retrospective cohort study compared maternal and neonatal outcomes of first postcancer pregnancies among women CRC survivors against randomly selected pregnancies of women with no cancer history. Logistic regression models were used to investigate a range of adverse outcomes independently associated with CRC and its surgical and adjunctive treatments.

RESULTS

Among 627,762 deliveries during the study period (1983-2007), 232 were first pregnancies following CRC. Whether following laparoscopic or open cancer surgery, these pregnancies were independently associated with a significantly increased risk of antepartum hemorrhage [odds ratios (ORs): 1.25; 2.13 for the respective procedures], postpartum hemorrhage (ORs: 1.61; 3.31), Cesarean delivery (ORs: 2.42; 4.24), infant low Apgar score (ORs: 1.32; 2.64), need for neonatal resuscitation (ORs: 1.49; 3.20), and special care admission (ORs: 1.42; 2.87). A history of open (but not laparoscopic) cancer surgery was associated with increased risk of gastrointestinal obstruction during pregnancy (OR 1.17) and prolonged postpartum hospitalization (OR 3.11). Neither was significantly associated with perinatal death. Among women with previous CRC, rectal (versus colonic) malignancy was independently associated with a significantly higher risk of overall maternal and neonatal adverse outcomes (ORs: 3.73 and 2.73, respectively), as was radiotherapy (ORs: 4.24 and 2.81, respectively). Chemotherapy was independently associated with a marginally but significantly higher risk of overall maternal but not neonatal outcomes (ORs: 1.11; 0.98). Open versus laparoscopic cancer surgery was associated with a significantly higher risk of antepartum and postpartum hemorrhage, low Apgar score, need for neonatal resuscitation, and neonatal special care admission.

CONCLUSIONS

Previous CRCs, particularly rectal and radiation-treated tumors, appear to confer an increased likelihood of adverse outcomes in subsequent pregnancies. Laparoscopic technique for CRC surgery may reduce adverse gestational outcomes.

Pregnancy after successful cancer treatment: what needs to be considered?

Over the last decade, advances in oncology led to improved treatment results and increasing numbers of long-term cancer survivors. Fulfilling the desire to have children is important for many patients after cancer treatment. Consequently, oncologists, gynecologists and obstetricians are seeing more patients who wish to conceive after treatment. The necessary prerequisites that should be considered when supporting a planned pregnancy after cancer treatment are discussed in this article. The possible consequences of chemotherapy and radiotherapy on the course of pregnancy and the health of the offspring, as well as the interactions between cancer and pregnancy, are reviewed with the focus on childhood cancer, malignant lymphomas, and breast cancer. Despite chemo- or radiotherapy, neither the teratogenic risk nor the risk of adventitious cancers appears to be increased for the offspring of cancer survivors. However, there is a slightly higher risk of miscarriage after chemotherapy. In case of radiation to the uterus, there is a higher risk of premature birth, intrauterine growth retardation, and increased perinatal mortality. The effect is more pronounced after prepubertal radiation than for postpubertal radiation. The former cancer patient's desire to conceive can nevertheless be supported, given that pregnancy and birth are closely monitored.

Genetic disease in the children of Danish survivors of childhood and adolescent cancer

PURPOSE

Preconception radiation and chemotherapy have the potential to produce germ cell mutations leading to genetic disease in the next generation. Dose-response relationships were evaluated between cancer treatments and untoward pregnancy outcomes.

PATIENTS AND METHODS

A case-cohort study was conducted involving 472 Danish survivors of childhood and adolescent cancer and their 1,037 pregnancies. Adverse outcomes included 159 congenital malformations, six chromosomal abnormalities, seven stillbirths, and nine neonatal deaths. Preconception radiation doses to the gonads, uterus, and pituitary gland and administered chemotherapy were quantified based on medical records and related to adverse outcomes using a generalized estimating equation model.

RESULTS

No statistically significant associations were found between genetic disease in children and parental treatment with alkylating drugs or preconception radiation doses to the testes in male and ovaries in female cancer survivors. Specifically, the risk of genetic disease was similar among the children of irradiated survivors when compared with nonirradiated survivors (relative risk [RR], 1.02; 95% CI, 0.59 to 1.44; P = .94). A statistically significant association between abdomino-pelvic irradiation and malformations, stillbirths, and neonatal deaths was not seen in the children of female survivors overall (P = .07) or in the children of mothers receiving high uterine doses (mean, 13.5 Gy; max, 100 Gy; RR, 2.3; 95% CI, 0.95 to 5.56).

CONCLUSION

Mutagenic chemotherapy and radiotherapy doses to the gonads were not associated with genetic defects in children of cancer survivors. However, larger studies need to be conducted to further explore potential associations between high-dose pelvic irradiation and specific adverse pregnancy outcomes.

Sperm banking and the cancer patient

The current concepts, recommendations, and principles of sperm banking as it pertains to the comprehensive care of young men of reproductive age with cancer are reviewed. Obstacles to sperm banking are addressed as well as future directions for fertility-preserving technologies. All cancer therapies-chemotherapy, radiation, and surgery-are potential threats to a man's reproductive potential. In addition, cancer itself can impair spermatogenesis. Thus, sperm cryopreservation prior to initiating life-saving cancer treatment offers men and their families the best chance to father biologically related children and should be offered to all men with cancer before treatment. Better patient and provider education, as well as deliberate, coordinated strategies at comprehensive cancer care centers are necessary to make fertility preservation for male cancer patients a priority during pretreatment planning.

Hospitalizations among children of survivors of childhood and adolescent cancer: a population-based cohort study

Curative but potentially mutagenic cancer therapy might lead to untoward disorders and increased hospitalization among the offspring of childhood cancer survivors. Hospitalizations in childhood were evaluated in a population-based cohort of 1,920 offspring of 3,963 childhood cancer survivors, 6,394 offspring of 5,657 siblings and 9,594 population-based comparisons. The Danish Cancer Registry, Central Population Register and National Hospital Register were used to identify study subjects and hospitalizations. The probability for children in the offspring cohorts of being hospitalized before a given age was estimated using the Kaplan-Meier method. Hospitalization rate ratios (HRRs) were calculated using a Cox proportional hazards model with population comparisons as referent. Little differences in hospitalization histories were seen among offspring in the 3 cohorts. HRRs of overall hospitalization was 1.05 (95% CI, 0.98-1.12) for offspring of survivors and 1.01 (95% CI, 0.97-1.05) for offspring of siblings, neither of which was significantly different from that of population comparisons. No significant associations were seen for most of the main diagnostic groups of diseases including infections and perinatal disorders. A 6-fold excess risk of hospitalization for malignant tumors in survivors' offspring, however, could largely be explained by hereditary cancer syndromes, and part of the 2-fold excess hospitalization for benign tumors might similarly be explained by an underlying genetic susceptibility or by increased surveillance of children born to survivors. Assuming that hospitalization is an indicator of multifactorial genetic disease, the findings provide further reassurance that cancer therapies do not confer a high risk of such conditions in offspring born after treatments.

Risk of birth abnormalities in the offspring of men with a history of cancer: a cohort study using Danish and Swedish national registries

Background

The potential mutagenic effects of cancer therapies and the growing number of young male cancer survivors have given rise to concern about the health of their offspring.

Methods

We identified all singleton children born alive in Denmark between 1994 and 2004 and in Sweden between 1994 and 2005 (n = 1 777 765). Of the 8670 children with a paternal history of cancer, 8162 were conceived naturally and 508 were conceived using assisted reproductive technologies (ARTs) (in vitro fertilization or intracytoplasmatic sperm injection). Of the 1 769 0795 children without a paternal history of cancer, 25 926 were conceived using ARTs. Associations between paternal history of cancer and risk of adverse birth outcomes of children conceived naturally or by ARTs were investigated using log-linear binomial models, yielding risk ratios (RRs) with 95% confidence intervals (CIs). All statistical tests were two-sided.

Results

The offspring of male cancer survivors were more likely to have major congenital abnormalities than the offspring of fathers with no history of cancer (RR = 1.17, 95% CI = 1.05 to 1.31, P = .0043, 3.7% vs 3.2%). However, the mode of conception (natural conception or ARTs) did not modify the association between paternal history of cancer and risk of congenital abnormalities (natural conception, RR = 1.17, 95% CI = 1.04 to 1.31; ARTs, RR = 1.22, 95% CI = 0.80 to 1.87, P_interaction = .84).

Conclusion

We observed a statistically significant but modest increase in the risk of major congenital abnormalities among offspring of males with a history of cancer, independent of the mode of conception.

A U-shaped dose-response relationship between x radiation and sex-linked recessive lethal mutation in male germ cells of Drosophila

We reported previously that low-dose X irradiation of DNA repair-proficient immature sperm of wild-type Drosophila melanogaster at a low dose rate (50 mGy/min) resulted in a mutation frequency that was lower than that in the sham-irradiated group. Therefore, a U-shaped dose-response relationship was suggested. Here we show that the dose-response curve is actually U-shaped by carrying out a large-scale sex-linked recessive lethal assay using Drosophila. No reduction of the mutation frequency was observed in a strain mutant for the nucleotide excision repair gene mei-9a (Drosophila homologue of human XPF). Introduction of a chromosome fragment containing mei-9+ into the mei-9a mutant strain restored the reduction of the mutation frequency in the low-dose-irradiated group. These results showed that DNA repair was responsible for the U-shaped dose-response relationship in Drosophila.

Wilms' tumour: a systematic review of risk factors and meta-analysis

Wilms' tumour comprises 95% of all renal cancers among children less than 15 years of age. The purpose of this review is to examine the existing literature on perinatal and environmental risk factors for Wilms' tumour. A search for epidemiological studies that examined risk factors for Wilms' tumour was undertaken in Medline, LILACS, ISI Web of Science and Dissertation Abstracts. A total of 37 studies, including 14 cohort, 21 case-control and 2 case-cohort studies, were identified that examined environmental and perinatal risk factors. Most studies were from Western Europe and North America, and among case-control studies, 16 used randomly selected population-based controls. We observed a significantly increased risk of Wilms' tumour with maternal exposure to pesticides prior to the child's birth (OR = 1.37 [95% CI 1.09, 1.73]), high birthweight (OR = 1.36 [95% CI 1.12, 1.64]) and preterm birth (OR = 1.44 [95% CI 1.14, 1.81]), although the results regarding pesticide exposure may be subject to publication bias (Egger's test, P = 0.09). Further analyses to adjust for the heterogeneity in the results for high birthweight and preterm birth did not statistically change the significance of the results. Additionally, an increased though not statistically significant risk of Wilms' tumour was associated with maternal hypertension (OR = 1.30 [95% CI 0.99, 1.72]), and, compared with the first born, being a second or later birth was associated with a significantly decreased risk (OR = 0.82 [95% CI 0.71, 0.95]). This review suggests a role for several perinatal and environmental risk factors in the aetiology of Wilms' tumour.

Pregnancy outcome after treatment for Wilms tumor: a report from the national Wilms tumor long-term follow-up study

PURPOSE

This study was undertaken to evaluate the effect of prior treatment with radiation therapy or chemotherapy for unilateral Wilms tumor (WT) diagnosed during childhood on pregnancy complications, birth weight, and the frequency of congenital malformations in live-born offspring.

PATIENTS AND METHODS

We reviewed pregnancy outcomes among female survivors and partners of male survivors of WT treated on National Wilms Tumor Studies 1, 2, 3, and 4 by using a maternal questionnaire and a review of both maternal and offspring medical records.

RESULTS

We received reports of 1,021 pregnancies with duration of 20 weeks or longer, including 955 live-born singletons, for whom 700 sets of maternal and offspring medical records were reviewed. Rates of hypertension complicating pregnancy (International Classification of Diseases [ICD] code 642), early or threatened labor (ICD-644) and malposition of the fetus (ICD-652) increased with increasing radiation dose in female patients. The percentages of offspring weighing less than 2,500 g at birth and of those having less than 37 weeks of gestation also increased with dose. There was no significant trend with radiation dose in the number of congenital anomalies recorded in offspring of female patients.

CONCLUSION

Women who receive flank radiation therapy as part of the treatment for unilateral WT are at increased risk of hypertension complicating pregnancy, fetal malposition, and premature labor. The offspring of these women are at risk for low birth weight and premature (ie, < 37 weeks gestation) birth. These risks must be considered in the obstetrical management of female survivors of WT.

Familial risks in nervous system tumours: joint Nordic study

Background:

Familial nervous system cancers are rare and limited data on familial aspects are available particularly on site-specific tumours.

Methods:

Data from five Nordic countries were used to analyse familial risks of nervous system tumours. Standardised incidence ratios (SIRs) were calculated for offspring of affected relatives compared with offspring of non-affected relatives.

Results:

The total number of patients with nervous system tumour was 63 307, of whom 32 347 belonged to the offspring generation. Of 851 familial patients (2.6%) in the offspring generation, 42 (4.7%) belonged to the families of a parent and at least two siblings affected. The SIR of brain tumours was 1.7 in offspring of affected parents; it was 2.0 in siblings and 9.4 in families with a parent and sibling affected. For spinal tumours, the SIRs were much higher for offspring of early onset tumours, 14.0 for offspring of affected parents and 22.7 for siblings. The SIRs for peripheral nerve tumours were 16.3 in offspring of affected parents, 27.7 in siblings and 943.9 in multiplex families.

Conclusion:

The results of this population-based study on medically diagnosed tumours show site-, proband- and age-specific risks for familial tumours, with implications for clinical genetic counselling and identification of the underlying genes.

The Swedish Family-Cancer Database 2009: prospects for histology-specific and immigrant studies

The Swedish Family-Cancer Database comprises a total of 11.8 million individuals covering the Swedish population of the past 100 years. Version VIII of the Database is described in the present article. Cancer cases were retrieved from the Swedish Cancer Registry for the period 1958-2006, including more than 1 million first primary cancers. The number of familial cancers in offspring is 14,000 when a parent was diagnosed with a concordant (same) cancer and the number of concordant siblings was 6,000. From the year 1993 onwards histopathological data according to the SNOMED classification were used, which entails advantages for certain cancers, such as breast cancer. Even though the specific morphological classification only covers a limited number of years, it does cover most familial cancers in the offspring generation. The Database records the country of birth for each subject. A total of 1.79 million individuals were foreign born, Finns and other Scandinavians being the largest immigrant groups. The cancer incidence in the first-generation immigrants was compared to that in native Swedes using standardised incidence ratios (SIRs) to measure relative risk. The SIRs ranged widely between the immigrant groups, from 1.9-fold for myeloma to 25-fold for melanoma. The differences in SIRs were smaller in the second-generation immigrants. The usefulness and the possible applications of the Family-Cancer Database have increased with increasing numbers of cases, and the numerous applications have been described in some 300 publications. Familial cancer studies are in the stimulating interphase of the flourishing disciplines of genetics and epidemiology.

Risk of cancer among children of cancer patients - a nationwide study in Finland

Cancer treatments have the potential to cause germline mutations that might increase the risk of cancer in the offspring of former cancer patients. This risk was evaluated in a population-based study of early onset cancer patients in Finland. Using the nationwide registry data, 26,331 children of pediatric and early onset cancer patients (diagnosed under age 35 between 1953 and 2004) were compared to 58,155 children of siblings. Cancer occurrence among the children was determined by linkage with the cancer registry, and the standardized incidence ratios (SIRs) were calculated comparing the observed number of cancers with that expected, based on rates in the general population of Finland. Among the 9,877 children born after their parent's diagnosis, cancer risk was increased (SIR 1.67; 95% CI 1.29-2.12). However, after removing those with hereditary cancer syndromes, this increase disappeared (SIR 1.03; 95% CI 0.74-1.40). The overall risk of cancer among the offspring of siblings (SIR 1.07; 95% CI 0.94-1.21) was the same as among the offspring of the patients with non hereditary cancer. Risk of cancer in offspring, born before their parents cancer diagnosis, was elevated (SIR 1.37, 95% CI 1.20-1.54), but removing hereditary syndromes resulted in a diminished and nonsignificant association (SIR 1.08, 95% CI 0.93-1.25). This study shows that offspring of cancer patients are not at an increased risk of cancer except when the patient has a cancer-predisposing syndrome. These findings are directly relevant to counseling cancer survivors with regard to family planning.

Reproductive outcomes in male childhood cancer survivors: a linked cancer-birth registry analysis

OBJECTIVE

To compare the risk of reproductive and infant outcomes between male childhood cancer survivors and a population-based comparison group.

DESIGN

Retrospective cohort study.

SETTING

Four US regions.

PARTICIPANTS

Cancer registries identified males younger than 20 years diagnosed with cancer from 1973 to 2000. Linked birth certificates identified first subsequent live offspring (N = 470). Comparison subjects were identified from remaining birth certificates, frequency-matched on year and age at fatherhood, and race/ethnicity (N = 4150).

MAIN EXPOSURE

Cancer diagnosis before age 20 years.

OUTCOME MEASURES

Pregnancy and infant outcomes identified from birth certificates.

RESULTS

Compared with infants born to unaffected males, offspring of cancer survivors had a borderline risk of having a birth weight less than 2500 g (relative risk, 1.43 [95% confidence interval, 0.99-2.05]) that was associated most strongly with younger age at cancer diagnosis and exposure to any chemotherapy (1.96 [1.22-3.17]) or radiotherapy (1.95 [1.14-3.35]). However, they were not at risk of being born prematurely, being small for gestational age, having malformations, or having an altered male to female ratio. Overall, female partners of male survivors were not more likely to have maternal complications recorded on birth records vs the comparison group. However, preeclampsia was associated with some cancers, especially central nervous system tumors (relative risk, 3.36 [95% confidence interval, 1.63-6.90]).

CONCLUSIONS

Most pregnancies resulting in live births among partners of male childhood cancer survivors were not at significantly greater risk of complications vs comparison subjects. However, there remains the possibility that prior cancer therapy may affect male germ cells with some effects on progeny and on female partners.