Ruth A. Kleinerman

International study of factors affecting human chromosome translocations

Chromosome translocations in peripheral blood lymphocytes of normal, healthy humans increase with age, but the effects of gender, race, and cigarette smoking on background translocation yields have not been examined systematically. Further, the shape of the relationship between age and translocation frequency (TF) has not been definitively determined. We collected existing data from 16 laboratories in North America, Europe, and Asia on TFs measured in peripheral blood lymphocytes by fluorescence in situ hybridization whole chromosome painting among 1933 individuals. In Poisson regression models, age, ranging from newborns (cord blood) to 85 years, was strongly associated with TF and this relationship showed significant upward curvature at older ages versus a linear relationship (p<0.001). Ever smokers had significantly higher TFs than non-smokers (rate ratio (RR)=1.19, 95% confidence interval (CI), 1.09-1.30) and smoking modified the effect of age on TFs with a steeper age-related increase among ever smokers compared to non-smokers (p<0.001). TFs did not differ by gender. Interpreting an independent effect of race was difficult owing to laboratory variation. Our study is three times larger than any pooled effort to date, confirming a suspected curvilinear relationship of TF with age. The significant effect of cigarette smoking has not been observed with previous pooled studies of TF in humans. Our data provide stable estimates of background TF by age, gender, race, and smoking status and suggest an acceleration of chromosome damage above age 60 and among those with a history of smoking cigarettes.

Radiation-sensitive genetically susceptible pediatric sub-populations

Major advances in pediatric cancer treatment have resulted in substantial improvements in survival. However, concern has emerged about the late effects of cancer therapy, especially radiation-related second cancers. Studies of childhood cancer patients with inherited cancer syndromes can provide insights into the interaction between radiation and genetic susceptibility to multiple cancers. Children with retinoblastoma (Rb), neurofibromatosis type 1 (NF1), Li-Fraumeni syndrome (LFS), and nevoid basal cell carcinoma syndrome (NBCCS) are at substantial risk of developing radiation-related second and third cancers. A radiation dose-response for bone and soft-tissue sarcomas has been observed in hereditary Rb patients, with many of these cancers occurring in the radiation field. Studies of NF1 patients irradiated for optic pathway gliomas have reported increased risks of developing another cancer associated with radiotherapy. High relative risks for second and third cancers were observed for a cohort of 200 LFS family members, especially children, possibly related to radiotherapy. Children with NBCCS are very sensitive to radiation and develop multiple basal cell cancers in irradiated areas. Clinicians following these patients should be aware of their increased genetic susceptibility to multiple primary malignancies enhanced by sensitivity to ionizing radiation.

Second Cancers After Squamous Cell Carcinoma and Adenocarcinoma of the Cervix

PURPOSEnAlthough cervical squamous cell carcinoma (SCC) and adenocarcinoma (AC) are both caused by human papillomavirus (HPV) infection, they differ in cofactors such as cigarette smoking. We assessed whether these cofactor differences translate into differences in second cancer risk.nnnPATIENTS AND METHODSnWe assessed second cancer risk among 85,109 cervical SCC and 10,280 AC survivors reported to population-based cancer registries in Denmark, Finland, Norway, Sweden, and the United States. Risks compared to the general population were assessed using standardized incidence ratios (SIR).nnnRESULTSnOverall cancer risk was significantly increased among both cervical SCC survivors (n = 10,559 second cancers; SIR, 1.31; 95% CI, 1.29 to 1.34) and AC survivors (n = 920 second cancers; SIR, 1.29; 95% CI, 1.22 to 1.38). Risks of HPV-related and radiation-related cancers were increased to a similar extent among cervical SCC and AC survivors. Although significantly increased in both groups when compared with the general population, risk of smoking-related cancers was significantly higher among cervical SCC than AC survivors (P = .015; SIR for cervical SCC = 2.07 v AC = 1.78). This difference was limited to lung cancer (SIR for cervical SCC = 2.69 v AC = 2.18; P = .026). The increased lung cancer risk among cervical AC survivors was observed for both lung SCC and lung AC. SIRs for second cancers of the colon, soft tissue, melanoma, and non-Hodgkins lymphoma were significantly higher among cervical AC than SCC survivors.nnnCONCLUSIONnThe second cancer profiles among cervical SCC and AC survivors mirror the similarities and differences in cofactors for these two histologies. Because smoking is not a cofactor for cervical AC, the increased lung cancer risk suggests a role for additional factors.

Agreement between diary records of time spent outdoors and personal ultraviolet radiation dose measurements.

Little is known about the validity of self‐recorded sun exposure and time spent outdoors for epidemiological research. The aims of the current study were to assess how well participants’ self‐recorded time outdoors compared to objective measurements of personal UVR doses. We enrolled 124 volunteers aged 40 and above who were identified from targeted subgroups of US radiologic technologists. Each volunteer was instructed to wear a polysulfone (PS) dosimeter to measure UVR on their left shoulder and to complete a daily activity diary, listing all activities undertaken in each 30u2003min interval between 9:00u2003A.M. and 5:00u2003P.M. during a 7u2003day period. In a linear regression model, self‐recorded daily time spent outdoors was associated with an increase of 8.2% (95% CI: 7.3–9.2%) in the personal UVR exposure with every hour spent outdoors. The amount of self‐recorded total daily time spent outdoors was better correlated with the personal daily UVR dose for activities conducted near noon time compared to activities conducted in the morning or late afternoon, and for activities often performed in the sun (e.g. gardening or recreation activities) compared to other outdoor activities (e.g. driving) in which the participant is usually shaded from the sun. Our results demonstrated a significant correlation between diary records of time spent outdoors with objective personal UVR dose measurements.

Radiation Dose and Subsequent Risk for Stomach Cancer in Long-term Survivors of Cervical Cancer

PURPOSEnTo assess the dose-response relationship for stomach cancer after radiation therapy for cervical cancer.nnnMETHODS AND MATERIALSnWe conducted a nested, matched case-control study of 201 cases and 378 controls among 53,547 5-year survivors of cervical cancer diagnosed from 1943 to 1995, from 5 international, population-based cancer registries. We estimated individual radiation doses to the site of the stomach cancer for all cases and to corresponding sites for the matched controls (overall mean stomach tumor dose, 2.56 Gy, range 0.03-46.1 and after parallel opposed pelvic fields, 1.63 Gy, range 0.12-6.3).nnnRESULTSnMore than 90% of women received radiation therapy, mostly with external beam therapy in combination with brachytherapy. Stomach cancer risk was nonsignificantly increased (odds ratio 1.27-2.28) for women receiving between 0.5 and 4.9 Gy to the stomach cancer site and significantly increased at doses ≥ 5 Gy (odds ratio 4.20, 95% confidence interval 1.41-13.4, Ptrend=.047) compared with nonirradiated women. A highly significant radiation dose-response relationship was evident when analyses were restricted to the 131 cases (251 controls) whose stomach cancer was located in the middle and lower portions of the stomach (Ptrend=.003), whereas there was no indication of increasing risk with increasing dose for 30 cases (57 controls) whose cancer was located in the upper stomach (Ptrend=.23).nnnCONCLUSIONSnOur findings show for the first time a significant linear dose-response relationship for risk of stomach cancer in long-term survivors of cervical cancer.

Analysis of retinoblastoma age incidence data using a fully stochastic cancer model.

Retinoblastoma (RB) is an important ocular malignancy of childhood. It has been commonly accepted for some time that knockout of the two alleles of the RB1 gene is the principal molecular target associated with the occurrence of RB. In this article, we examine the validity of the two‐hit theory for RB by comparing the fit of a stochastic model with two or more mutational stages. Unlike many such models, our model assumes a fully stochastic stem cell compartment, which is crucial to its behavior. Models are fitted to a population‐based dataset comprising 1,553 cases of RB for the period 1962–2000 in Great Britain (England, Scotland and Wales). The population incidence of RB is best described by a fully stochastic model with two stages, although models with a deterministic stem cell compartment yield equivalent fit; models with three or more stages fit much less well. The results strongly suggest that knockout of the two alleles of the RB1 gene is necessary and may be largely sufficient for the development of RB, in support of Knudsons two‐hit hypothesis.

Vision-Targeted Health-Related Quality of Life in Adult Survivors of Retinoblastoma

Importance Retinoblastoma survivors are at risk for adverse oculo-visual outcomes. Limited data are available regarding long-term vision-targeted health-related quality of life (HRQoL) of adult retinoblastoma survivors. Objective To examine vision-targeted HRQoL as reported on the 25-item National Eye Institute Visual Field Questionnaire for overall and specific scale scores among adult survivors of retinoblastoma. Design, Setting, and Participants The Retinoblastoma Survivor Study is a retrospective cohort of adult retinoblastoma survivors treated at 3 academic medical centers in New York between 1932 and 1994. Participants completed a comprehensive questionnaire between April 2008 and June 2010. Items were scored in January 2013 and preliminary analyses were performed in July 2015. Models were finalized in May 2017. Main Outcomes and Measures Self-reported vision-targeted HRQoL as reported on the 25-item National Eye Institute Visual Field Questionnaire. Items are scored from 0 to 100, with 100 representing the highest quality of life. Results Among 470 adult retinoblastoma survivors (53.6% with bilateral disease; 52.1% female; 86.4% white and non-Hispanic; mean age at study, 43.3 years; range, 18.0-77.0 years), 86% had at least 1 eye removed (1 eye, 74.5%; both eyes, 11.5%); 56.5% were previously treated with radiotherapy; and 61.3% rated their eyesight as excellent/good while 16.2% reported complete blindness. The overall mean (SD) VFQ composite score for all survivors was 81.1 (17.2) (mean [SD] score for unilateral retinoblastoma survivors, 91.4 [7.7]; bilateral retinoblastoma survivors, 72.3 [18.2]; difference between survivors with unilateral and bilateral disease, 19.1 [95% CI, 16.5-21.7; Pu2009<u2009.001]). Prior exposure to radiotherapy was not associated with decreased overall VFQ (&bgr;u2009=u2009−0.08; 95% CI, −0.15 to 0.002; Pu2009=u2009.06) but was related to a few specific subdomains of visual functioning. Conclusions and Relevance These findings suggest retinoblastoma-related oculo-visual problems are associated with functional status and vision-targeted HRQoL of adult survivors, particularly among those with bilateral disease.

Abstract 1333: Specific RB1 mutations and risk of subsequent neoplasms among survivors of hereditary retinoblastoma.

The retinoblastoma tumor suppressor gene (RB1) is a key regulator of cell cycle control, most notably through E2F transcription factor binding. Deregulation of RB1 is important in many cancers. Survivors of hereditary retinoblastoma, caused by a germline mutation in RB1, experience substantially elevated risks for subsequent neoplasms, particularly bone and soft tissue sarcomas and melanomas. Oncogenic RB1 mutations arise from a range of DNA alterations and occur throughout the gene. No previous study has evaluated how the specific location and functional consequences of these RB1 mutations may differentially confer risk for specific subsequent neoplasms. As part of a biomarker study nested within a long-term follow-up study of the risk of subsequent cancers in retinoblastoma survivors, we identified germline RB1 mutations in 76/80 (95%) survivors of hereditary retinoblastoma who developed at least one subsequent neoplasm and had sufficient DNA for mutation testing (median follow-up time=47 years, range 7-71 years). Survivors were classified into four groups according to whether they ever developed a soft tissue sarcoma (STS, N=47), melanoma (without STS, N=10), bone tumor (without STS, N=5), or another type of subsequent malignant neoplasm (N=14). The identified mutations were distributed throughout RB1, from the promoter through exon 25. Nonsense, frameshift, or splice mutations that resulted in premature termination of the RB1 residue sequence were identified in 51 (67%) survivors, with the remaining classified as having loss of multiple exons (N=6), loss or rearrangement of a single exon (N=5), a splice mutation (N=7), a missense mutation (N=4), or an intronic substitution with unknown consequence (N=3). Preliminary analyses indicated that RB1 mutations resulting in loss of >2 exons were more common in survivors with a subsequent STS (40/47, 85%) than those with a subsequent melanoma (6/10, 60%) or bone tumor (2/5, 40%; Fisher9s exact P Citation Format: Lindsay M. Morton, Jeannette R. Wong, Brenda L. Gallie, David H. Abramson, Johanna M. Seddon, Michael Dean, Bert Gold, Alisa M. Goldstein, Ruth A. Kleinerman, Margaret A. Tucker. Specific RB1 mutations and risk of subsequent neoplasms among survivors of hereditary retinoblastoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1333. doi:10.1158/1538-7445.AM2013-1333