The ICRP, MELODI, and ALLIANCE workshop on effects of ionizing radiation exposure in offspring and next generations: a summary of discussions.

PURPOSE: Task Group 121 - Effects of ionizing radiation exposure in offspring and next generations - is a task group under the Committee 1 of the International Commission on Radiological Protection (ICRP), approved by the Main Commission on 18th November 2021. The main goals of Task Group 121 are to (1) review and update the scientific literature of relevance to radiation-related effects in the offspring of parent(s) exposed to ionizing radiation in both human and non-human biota; (2) to assess preconceptional and intrauterine effects of radiation exposure and related morbidity and mortality; and, (3) to provide advice about the level of evidence and how to consider these preconceptional and postconceptional effects in the system of radiological protection for humans and non-human biota. METHODS: The Task Group is reviewing relevant literature since Publication 90 'Biological effects after prenatal irradiation (embryo and fetus)' (2003) and will include radiation-related effects on future generations in humans, animals, and plants. This review will be conducted to account for the health effects on offspring and subsequent generations in the current system of radiological protection. Radiation detriment calculation will also be reviewed. Finally, preliminary recommendations will be made to update the integration of health effects in offspring and next generations in the system of radiological protection. RESULTS: A Workshop, jointly organized by ICRP Task Group 121 and European Radiation Protection Research Platforms MELODI and ALLIANCE was held in Budapest, Hungary, from 31st May to 2nd June 2022. Participants discussed four important topics: (1) hereditary and epigenetic effects due to exposure of the germ cell line (preconceptional exposure), (2) effects arising from exposure of the embryo and fetus (intrauterine exposure), (3) transgenerational effects on biota, and (4) its potential impact on the system of radiological protection. CONCLUSIONS: Based on the discussions and presentations during the breakout sessions, newer publications, and gaps on the current scientific literature were identified. For instance, there are some ongoing systematic reviews and radiation epidemiology reviews of intrauterine effects. There are newer methods of Monte Carlo simulation for fetal dosimetry, and advances in radiation genetics, epigenetics, and radiobiology studies. While the current impact of hereditary effects on the global detriment was reported as small, the questions surrounding the effects of radiation exposure on offspring and the next generation are crucial, recurring, and with a major focus on exposed populations. This article summarizes the workshop discussions, presentations, and conclusions of each topic and introduces the special issue of the International Journal of Radiation Biology resulting from the discussions of the meeting.

Radiological protection in human research ethics using a case study: toward update of the ICRP Publication 62.

The benefits of biomedical research involving humans are well recognised, along with the need for conformity to international standards of science and ethics. When human research involves radiation imaging procedures or radiotherapy, an extra level of expert review should be provided from the point of view of radiological protection. The relevant publication of the International Commission for Radiological Protection (ICRP) is now three decades old and is currently undergoing an update. This paper aims to provoke discussions on how the risks of radiation dose and the benefits of research should be assessed, using a case study of diagnostic radiology involving volunteers for whom there is no direct benefit. Further, the paper provides the current understanding of key concepts being considered for review and revision-such as the dose constraint and the novel research methods on the horizon, including radiation biology and epidemiology. The analysis revisits the perspectives described in the ICRP Publication 62, and considers the recent progress in both radiological protection ethics and medical research ethics.

A Multimedia Strategy to Integrate Introductory Broad-Based Radiation Science Education in US Medical Schools.

US physicians in multiple specialties who order or conduct radiological procedures lack formal radiation science education and thus sometimes order procedures of limited benefit or fail to order what is necessary. To this end, a multidisciplinary expert group proposed an introductory broad-based radiation science educational program for US medical schools. Suggested preclinical elements of the curriculum include foundational education on ionizing and nonionizing radiation (eg, definitions, dose metrics, and risk measures) and short- and long-term radiation-related health effects as well as introduction to radiology, radiation therapy, and radiation protection concepts. Recommended clinical elements of the curriculum would impart knowledge and practical experience in radiology, fluoroscopically guided procedures, nuclear medicine, radiation oncology, and identification of patient subgroups requiring special considerations when selecting specific ionizing or nonionizing diagnostic or therapeutic radiation procedures. Critical components of the clinical program would also include educational material and direct experience with patient-centered communication on benefits of, risks of, and shared decision making about ionizing and nonionizing radiation procedures and on health effects and safety requirements for environmental and occupational exposure to ionizing and nonionizing radiation. Overarching is the introduction to evidence-based guidelines for procedures that maximize clinical benefit while limiting unnecessary risk. The content would be further developed, directed, and integrated within the curriculum by local faculties and would address multiple standard elements of the Liaison Committee on Medical Education and Core Entrustable Professional Activities for Entering Residency of the Association of American Medical Colleges.

Age effects on radiation response: summary of a recent symposium and future perspectives.

One of the principal uncertainties when estimating population risk of late effects from epidemiological data is that few radiation-exposed cohorts have been followed up to extinction. Therefore, the relative risk model has often been used to estimate radiation-associated risk and to extrapolate risk to the end of life. Epidemiological studies provide evidence that children are generally at higher risk of cancer induction than adults for a given radiation dose. However, the strength of evidence varies by cancer site and questions remain about site-specific age at exposure patterns. For solid cancers, there is a large body of evidence that excess relative risk (ERR) diminishes with increasing age at exposure. This pattern of risk is observed in the Life Span Study (LSS) as well as in other radiation-exposed populations for overall solid cancer incidence and mortality and for most site-specific solid cancers. However, there are some disparities by endpoint in the degree of variation of ERR with exposure age, with some sites (e.g., colon, lung) in the LSS incidence data showing no variation, or even increasing ERR with increasing age at exposure. The pattern of variation of excess absolute risk (EAR) with age at exposure is often similar, with EAR for solid cancers or solid cancer mortality decreasing with increasing age at exposure in the LSS. We shall review the human data from the Japanese LSS cohort, and a variety of other epidemiological data sets, including a review of types of medical diagnostic exposures, also some radiobiological animal data, all bearing on the issue of variations of radiation late-effects risk with age at exposure and with attained age. The paper includes a summary of several oral presentations given in a Symposium on "Age effects on radiation response" as part of the 67th Annual Meeting of the Radiation Research Society, held virtually on 3-6 October 2021.

Radiation exposures in pregnancy, health effects and risks to the embryo/foetus-information to inform the medical management of the pregnant patient.

Generally, intentional exposure of pregnant women is avoided as far as possible in both medical and occupational situations. This paper aims to summarise available information on sources of radiation exposure of the embryo/foetus primarily in medical settings. Accidental and unintended exposure is also considered. Knowledge on the effects of radiation exposure on the developing embryo/foetus remains incomplete-drawn largely from animal studies and two human cohorts but a summary is provided in relation to the key health endpoints of concern, severe foetal malformations/death, future cancer risk, and future impact on cognitive function. Both the specific education and training and also the literature regarding medical management of pregnant females is in general sparse, and consequently the justification and optimisation approaches may need to be considered on a case by case basis. In collating and reviewing this information, several suggestions for future basic science research, education and training, and radiation protection practice are identified.

Multiphase acquisitions in pediatric abdominal-pelvic CT are a common practice and contribute to unnecessary radiation dose.

BACKGROUND: Many patients at our pediatric hospital have had a contrast-enhanced CT of the abdomen and pelvis performed by an outside imaging facility before admission. We have noticed that many of these exams are multiphase, which may contribute to unnecessary radiation dose. OBJECTIVE: To determine the frequency of multiphase acquisitions and radiation dose indices in contrast-enhanced CTs of the abdomen and pelvis performed by outside imaging facilities in patients who were subsequently transferred to our pediatric hospital for care, and compare these metrics to contrast-enhanced CTs of the abdomen and pelvis performed internally. MATERIALS AND METHODS: A retrospective analysis was performed of contrast-enhanced CTs of the abdomen and pelvis from outside imaging facilities uploaded to our picture archiving and communication system (PACS) between January 1, 2012, and December 31, 2015. CT images and dose pages were reviewed to determine the number of phases and dose indices (CT dose index-volume [CTDIvol], dose-length product, size-specific dose estimate). Exams for abdominal or pelvic mass, trauma or urinary leak indications were excluded. Data were compared to internally acquired contrast-enhanced CTs of the abdomen and pelvis by querying the American College of Radiology (ACR) Dose Index Registry. This review was institutional review board and HIPAA compliant. RESULTS: There were 754 contrast-enhanced CTs of the abdomen and pelvis from 104 outside imaging facilities. Fifty-three percent (399/754) had 2 phases, and 2% (14/754) had 3 or more phases. Of the 939 contrast-enhanced CTs of the abdomen and pelvis performed internally, 12% (115) were multiphase exams. Of 88% (664) contrast-enhanced CTs of the abdomen and pelvis from outside imaging facilities with dose data, CTDIvol was 2.7 times higher than our institution contrast-enhanced CTs of the abdomen and pelvis (939) for all age categories as defined by the ACR Dose Index Registry (mean: 9.4 vs. 3.5 mGy, P<0.0001). The majority (74%) of multiphase exams were performed by 9 of 104 outside imaging facilities. CONCLUSION: Multiphase acquisitions in routine contrast-enhanced CT of the abdomen and pelvis exams at outside imaging facilities are more frequent than those at a dedicated pediatric institution and contribute to unnecessary radiation dose. A contrast-enhanced CT of the abdomen and pelvis exam from an outside imaging facility with two passes may have as much as four times to six times the dose as the same exam performed with a single pass at a pediatric imaging center. We advocate for imaging facilities with high multiphase rates to eliminate multiple phases from routine contrast-enhanced CT of the abdomen and pelvis exams in children.

Using the American College of Radiology Dose Index Registry to Evaluate Practice Patterns and Radiation Dose Estimates of Pediatric Body CT.

OBJECTIVE: Imaging registries afford opportunities to study large, heterogeneous populations. The purpose of this study was to examine the American College of Radiology CT Dose Index Registry (DIR) for dose-related demographics and metrics of common pediatric body CT examinations. MATERIALS AND METHODS: Single-phase CT examinations of the abdomen and pelvis and chest submitted to the DIR over a 5-year period (July 2011-June 2016) were evaluated (head CT frequency was also collected). CT examinations were stratified into five age groups, and examination frequency was determined across age and sex. Standard dose indexes (volume CT dose index, dose-length product, and size-specific dose estimate) were categorized by body part and age. Contributions to the DIR were also categorized by region and practice type. RESULTS: Over the study period 411,655 single-phase pediatric examinations of the abdomen and pelvis, chest, and head, constituting 5.7% of the total (adult and pediatric) examinations, were submitted to the DIR. Head CT was the most common examination across all age groups. The majority of all scan types were performed for patients in the second decade of life. Dose increased for all scan types as age increased; the dose for abdominopelvic CT was the highest in each age group. Even though the DIR was queried for single-phase examinations only, as many as 32.4% of studies contained multiple irradiation events. When these additional scans were included, the volume CT dose index for each scan type increased. Among the studies in the DIR, 99.8% came from institutions within the United States. Community practices and those that specialize in pediatrics were nearly equally represented. CONCLUSION: The DIR provides valuable information about practice patterns and dose trends for pediatric CT and may assist in establishing diagnostic reference levels in the pediatric population.

Downstream Breast Imaging Following Screening Mammography in Medicare Patients with Advanced Cancer: A Population-Based Study.

BACKGROUND: Screening tests are generally not recommended in patients with advanced cancer and limited life expectancy. Nonetheless, screening mammography still occurs and may lead to follow-up testing. OBJECTIVE: We assessed the frequency of downstream breast imaging following screening mammography in patients with advanced colorectal or lung cancer. DESIGN: Population-based study. PARTICIPANTS: The study included continuously enrolled female fee-for-service Medicare beneficiaries ≥65 years of age with advanced colorectal (stage IV) or lung (stage IIIB-IV) cancer reported to a Surveillance, Epidemiology, and End Results (SEER) registry between 2000 and 2011. MAIN MEASURES: We assessed the utilization of diagnostic mammography, breast ultrasound, and breast MRI following screening mammography. Logistic regression models were used to explore independent predictors of utilization of downstream tests while controlling for cancer type and patient sociodemographic and regional characteristics. KEY RESULTS: Among 34,127 women with advanced cancer (23% colorectal; 77% lung cancer; mean age at diagnosis 75 years), 9% (n = 3159) underwent a total of 5750 screening mammograms. Of these, 11% (n = 639) resulted in at least one subsequent diagnostic breast imaging examination within 9 months. Diagnostic mammography was most common (9%; n = 532), followed by ultrasound (6%; n = 334) and MRI (0.2%; n = 14). Diagnostic mammography rates were higher in whites than African Americans (OR, 1.6; p <0.05). Higher ultrasound utilization was associated with more favorable economic status (OR, 1.8; p <0.05). CONCLUSIONS: Among women with advanced colorectal and lung cancer, 9% continued screening mammography, and 11% of these screening studies led to at least one additional downstream test, resulting in costs with little likelihood of meaningful benefit.

Cancer-directed therapy and potential impact on survivals in nonresected hepatocellular carcinoma: SEER-Medicare population study.

AIM: To investigate determinants of receiving cancer-directed therapies and their potential survival impact in nonresected hepatocellular carcinoma (HCC) Materials & methods: Nonsurgically resected HCC patients between 2000 and 2010 were stratified by American Joint Committee on Cancer staging and the type of therapy. Predictors of receiving therapy were identified and implication on survival was evaluated. RESULTS: Out of 9239 patients included, those receiving any therapy demonstrated prolonged overall survival with following median overall survival (months): ablation (30.8), Yttrium-90 (15.6), transcatheter arterial chemoembolization (15.5), Sorafenib (5.6), versus no cancer-directed therapy (3.7; p-values <0.001). Overall, 36% of patients received cancer-directed therapy including 47% with stage I/II. Favorable sociodemographic factors predicted receipt of percutaneous locoregional therapies (p-values <0.05). DISCUSSION & CONCLUSION: There appears to be significant disparity in care of nonresected HCC patients with significant underutilization of cancer-directed therapies.

Trainees May Add Value to Patient Care by Decreasing Addendum Utilization in Radiology Reports.

OBJECTIVE: The purpose of this study was to evaluate the impact of trainee involvement and other factors on addendum rates in radiology reports. MATERIALS AND METHODS: This retrospective study was performed in a tertiary care pediatric hospital. From the institutional radiology data repository, we extracted all radiology reports from January 1 to June 30, 2016, as well as trainee (resident or fellow) involvement, imaging modality, patient setting (emergency, inpatient, or outpatient), order status (routine vs immediate), time of interpretation (regular work hours vs off-hours), radiologist's years of experience, and sex. We grouped imaging modalities as advanced (CT, MRI, and PET) or nonadvanced (any modality that was not CT, MRI, or PET) and radiologist experience level as ≤ 20 years or > 20 years. Our outcome measure was the rate of addenda in radiology reports. Statistical analysis was performed using multivariate logistic regression. RESULTS: From 129,033 reports finalized during the study period, 418 (0.3%) had addenda. Reports generated without trainees were 12 times more likely than reports with trainee involvement to have addenda (odds ratio [OR] = 12.2, p < 0.001). Advanced imaging studies were more likely than nonadvanced studies to be associated with addendum use (OR = 4.7, p < 0.001). Reports generated for patients in emergency or outpatient settings had a slightly higher likelihood of addendum use than those in an inpatient setting (OR = 1.5, p = 0.04; and OR = 1.3, p = 0.04, respectively). Routine orders had a slightly higher likelihood of addendum use compared with immediate orders (OR = 1.3, p = 0.01). We found no difference in addendum use by radiologist's sex, radiologist's years of experience, emergency versus outpatient setting, or time of interpretation. CONCLUSION: Trainees may add value to patient care by decreasing addendum rates in radiology reports.

Women's Leadership in the ACR, 2001-2015.

PURPOSE: To assess the trends of women in voluntary leadership roles in the ACR from 2001 to 2015. METHODS: Retrospective leadership records from 2001 to 2015 were collected from the ACR Membership Database based on member demographics, gender, and participation in leadership roles at the national and state level. Data were sorted by gender and year to assess the proportion of women in each leadership position relative to total member/representation counts. RESULTS: Overall, there were increasing numbers of women represented in ACR leadership. From 2001 to 2015, there were increasing rates of women achieving fellowship in the College (7%-11%), now at parity with male member rates. Representation by women has risen from 7% to 21% for state chapter presidents and from 14% to 18% for state councilors. Comparing rolling 5-year averages from 2001-2005 and 2011-2015 showed statistically significant increases (P < .05) in these leadership roles. Women members of the council steering committee rose from 13% in 2001 to 19% in 2015, peaking at 24% in 2014. The Board of Chancellors (BOC) showed the largest increase in women, from 9% to 33%, with a peak at 37% in 2014. However, no BOC chairs were women, one council speaker was a woman, two women were ACR presidents, and two women were vice presidents. CONCLUSIONS: Women's participation in ACR leadership has increased significantly at the state level and in fellowship recognition. Although there are increasing numbers of women on the BOC, top positions remain male-dominated at the national level.

Prevalence of Unanticipated Events Associated With MRI Examinations: A Benchmark for MRI Quality, Safety, and Patient Experience.

PURPOSE: To determine the prevalence of unanticipated events (UE) associated with MRI examinations in a multicenter academic radiology department. METHODS: UE reported by MRI technologists for examinations performed between June 2013 and November 2014 on 17 scanners in a university- and community-affiliated single health system were retrospectively reviewed. Events were categorized into the following categories: (1) problems with orders and scheduling; (2) scan delays; (3) unanticipated foreign bodies; (4) non-contrast-related patient events (eg, patient motion, discomfort, claustrophobia, need for sedation); (5) contrast-related patient events; and (6) technical acquisition issues. Logistic regression analysis of UE was performed after adjusting based on scanner site (university- vs community-affiliated hospital), hospital setting (outpatient [OP] vs mixed outpatient and inpatient [OP/IP]), and timing of the scan (business days vs weekends/holidays). RESULTS: A total of 34,587 MRI examinations were assessed (87% university-affiliated; 58% OP) with 5775 (16.7%) UE (1.9% of patients had more than one category event). Rates of UE for each category were as follows: 1.9% orders and scheduling, 3.3% delays in scan, 0.5% foreign bodies, 10.4% non-contrast-related patient events, 1.3% contrast-related patient events, and 1.5% technical issues. After adjustment for location of scanner, clinical setting, and timing of the scan, the rate of overall UE was significantly higher in university-affiliated sites (coefficient, 0.09 [95% confidence interval (CI), 0.07-0.10]; P < .001), in scans performed in the mixed OP/IP setting (coefficient, 0.09 [95% CI, 0.08-0.09]; P < .001), and in scans performed during weekends/holidays (coefficient, 0.02 [95% CI, 0.01-0.04]; P < .001). CONCLUSIONS: UE associated with MRI examinations are common (16.7%), with the majority being patient-related issues unrelated to contrast administration.

Breast Cancer Screening in Patients With Newly Diagnosed Lung and Colorectal Cancer: A Population-Based Study of Utilization.

PURPOSE: To assess breast cancer screening utilization in Medicare beneficiaries with colorectal and lung cancer versus cancer-free controls. METHODS: Female fee-for-service Medicare beneficiaries who were ≥67 years old and diagnosed with lung or colorectal cancer between 2000 and 2011 and who reported to a Surveillance, Epidemiology, and End Results (SEER) registry (case group) were followed for 2 years after their diagnoses, unless death, a diagnosis of breast cancer, or the end of 2013 came first. A similar number of cancer-free controls were individually matched to cases by age, race, registry region, and follow-up time. Screening utilization was defined as the percentage of women with ≥1 screening mammogram during follow-up. RESULTS: Overall, 104,164 cases (48% colorectal, 52% lung; 30% advanced cancer) and 104,164 controls were included. Among women with lung or colorectal cancer, 22% underwent ≥1 screening mammogram versus 26% of controls (odds ratio [OR] 0.80; 95% confidence interval [CI] 0.78-0.82). Stratified by cancer type, 28% of colorectal cancer cases versus 29% of controls (OR 0.98; 95% CI 0.95-1.01) and 17% of lung cancer cases versus 23% of controls (OR 0.63; 95% CI 0.60-0.65) received ≥1 mammogram. When stratified by stage, 8% with advanced cancer versus 18% of controls (OR 0.33; 95% CI 0.31-0.35) and 30% with early-stage cancer versus 30% of controls (OR 1; 95% CI 0.97-1.02) underwent ≥1 mammogram. CONCLUSION: Screening mammography utilization rates are similar between Medicare beneficiaries with early-stage cancer versus controls. Although the majority of patients with advanced-stage cancer appropriately do not pursue screening mammography, a small number (8%) continue with screening.

Assessment of Added Value of Noncontrast to Contrast-Enhanced Abdominal Computed Tomography Scan for Characterization of Hypervascular Liver Metastases.

Assess the added value of nonenhanced computed tomography (NECT) to contrast-enhanced CT (CECT) of the abdomen for characterization of hypervascular liver metastases and incidental findings. Institutional review board approved, Health Insurance Probability and Accountability Act compliant, retrospective study of patients with melanoma, neuroendocrine tumor, or thyroid cancer. First available triphasic abdomen CT after initial diagnosis was reviewed by 3 radiologists. The 3 most suspicious lesions were characterized on the CECT as benign or malignant and then recharacterized after reviewing the NECT with CECT. Incidental renal and adrenal lesions were characterized similarly. Diagnostic performance of CECT vs its combination with NECT was assessed. Statistical significance level was set at P < 0.05. A total of 81 patients were included (mean age = 55 years; 52% male; 64% with liver lesions; 27% and 11% with incidental renal and adrenal lesions, respectively). Percentage area under the curve and 95% CI of CECT vs combination with NECT for characterization of liver metastases was 98(94-100) vs 99(96-100) for reviewer 1 (P = 0.35), 93(86-100) vs 94(87-100) for reviewer 2 (P = 0.23), and 96(90-100) vs 99(97-100) for reviewer 3 (P = 0.32). Mean difference in area under the curve and 95% CI between 2 protocols for characterization of liver, renal, and adrenal lesions were -0.007(-0.05 to 0.04) (P = 0.63), -0.09(-0.25 to 0.07) (P = 0.22), and -0.01(-0.05 to 0.02) (P = 0.27), respectively. After addition of NECT, confidence level for lesion characterization increased 4%-15% for liver metastases, 18%-59% and 33%-67% for renal and adrenal lesions, respectively. In conclusion, while addition of NECT to CECT improved radiologist' confidence, there was no statistically significant change in characterization of hypervascular liver metastases or incidental renal and adrenal lesions.