Risk of hematological malignancies from CT radiation exposure in children, adolescents and young adults.

Over one million European children undergo computed tomography (CT) scans annually. Although moderate- to high-dose ionizing radiation exposure is an established risk factor for hematological malignancies, risks at CT examination dose levels remain uncertain. Here we followed up a multinational cohort (EPI-CT) of 948,174 individuals who underwent CT examinations before age 22 years in nine European countries. Radiation doses to the active bone marrow were estimated on the basis of body part scanned, patient characteristics, time period and inferred CT technical parameters. We found an association between cumulative dose and risk of all hematological malignancies, with an excess relative risk of 1.96 (95% confidence interval 1.10 to 3.12) per 100 mGy (790 cases). Similar estimates were obtained for lymphoid and myeloid malignancies. Results suggest that for every 10,000 children examined today (mean dose 8 mGy), 1-2 persons are expected to develop a hematological malignancy attributable to radiation exposure in the subsequent 12 years. Our results strengthen the body of evidence of increased cancer risk at low radiation doses and highlight the need for continued justification of pediatric CT examinations and optimization of doses.

Brain cancer after radiation exposure from CT examinations of children and young adults: results from the EPI-CT cohort study.

BACKGROUND: The European EPI-CT study aims to quantify cancer risks from CT examinations of children and young adults. Here, we assess the risk of brain cancer. METHODS: We pooled data from nine European countries for this cohort study. Eligible participants had at least one CT examination before age 22 years documented between 1977 and 2014, had no previous diagnosis of cancer or benign brain tumour, and were alive and cancer-free at least 5 years after the first CT. Participants were identified through the Radiology Information System in 276 hospitals. Participants were linked with national or regional registries of cancer and vital status, and eligible cases were patients with brain cancers according to WHO International Classification of Diseases for Oncology. Gliomas were analysed separately to all brain cancers. Organ doses were reconstructed using historical machine settings and a large sample of CT images. Excess relative risks (ERRs) of brain cancer per 100 mGy of cumulative brain dose were calculated with linear dose-response modelling. The outcome was the first reported diagnosis of brain cancer after an exclusion period of 5 years after the first electronically recorded CT examination. FINDINGS: We identified 948 174 individuals, of whom 658 752 (69%) were eligible for our study. 368 721 (56%) of 658 752 participants were male and 290 031 (44%) were female. During a median follow-up of 5·6 years (IQR 2·4-10·1), 165 brain cancers occurred, including 121 (73%) gliomas. Mean cumulative brain dose, lagged by 5 years, was 47·4 mGy (SD 60·9) among all individuals and 76·0 mGy (100·1) among people with brain cancer. A significant linear dose-response relationship was observed for all brain cancers (ERR per 100 mGy 1·27 [95% CI 0·51-2·69]) and for gliomas separately (ERR per 100 mGy 1·11 [0·36-2·59]). Results were robust when the start of follow-up was delayed beyond 5 years and when participants with possibly previously unreported cancers were excluded. INTERPRETATION: The observed significant dose-response relationship between CT-related radiation exposure and brain cancer in this large, multicentre study with individual dose evaluation emphasises careful justification of paediatric CTs and use of doses as low as reasonably possible. FUNDING: EU FP7; Belgian Cancer Registry; La Ligue contre le Cancer, L'Institut National du Cancer, France; Ministry of Health, Labour and Welfare of Japan; German Federal Ministry of Education and Research; Worldwide Cancer Research; Dutch Cancer Society; Research Council of Norway; Consejo de Seguridad Nuclear, Generalitat de Catalunya, Spain; US National Cancer Institute; UK National Institute for Health Research; Public Health England.

Risk of Meningioma after CT of the Head.

Purpose To investigate the association between exposure to head computed tomography (CT) and subsequent risk of meningioma. Materials and Methods The study was approved by the local ethics committee. A cohort of 26 370 subjects was retrospectively collected from a radiology archive of CT examinations of the head performed from 1973 through 1992. For comparison, an age- and sex-matched cohort of 96 940 subjects who were not exposed to CT (unexposed cohort) was gathered. The risk of meningioma was assessed by using data from the Swedish Cancer Registry; however, one-third of patients with meningioma had to be excluded because they either had a prevalent meningioma or other brain tumor at the first CT examination or had undergone radiation treatment to the head. Hazard ratios (HRs) were calculated from time of exposure to the occurrence of meningioma or death or until December 31, 2010, with logistic regression. Results Comparison of exposed and unexposed cohorts showed that there was no statistically significant increase in the risk of meningioma after exposure to CT of the head (HR: 1.49; 95% confidence interval: 0.97, 2.30; P = .07). If incident cases at the time of the first CT examination were not excluded, the risk of meningioma would have been falsely increased (HR: 2.28; 95% confidence interval: 1.56, 3.33; P = .0001). Conclusion When prevalent cases of meningioma at first exposure to CT of the head are excluded, no statistically significant increase in risk of meningioma was found among exposed subjects compared with unexposed control subjects. © RSNA, 2017.

Stomach Cancer Following Hodgkin Lymphoma, Testicular Cancer and Cervical Cancer: A Pooled Analysis of Three International Studies with a Focus on Radiation Effects.

To further understand the risk of stomach cancer after fractionated high-dose radiotherapy, we pooled individual-level data from three recent stomach cancer case-control studies. These studies were nested in cohorts of five-year survivors of first primary Hodgkin lymphoma (HL), testicular cancer (TC) or cervical cancer (CX) from seven countries. Detailed data were abstracted from patient records and radiation doses were reconstructed to the site of the stomach cancer for cases and to the corresponding sites for matched controls. Among 327 cases and 678 controls, mean doses to the stomach were 15.3 Gy, 24.7 Gy and 1.9 Gy, respectively, for Hodgkin lymphoma, testicular cancer and cervical cancer survivors, with an overall mean dose of 10.3 Gy. Risk increased with increasing radiation dose to the stomach cancer site (P < 0.001) with no evidence of nonlinearity or of a downturn at the highest doses (≥35 Gy). The pooled excess odds ratio per Gy (EOR/Gy) was 0.091 [95% confidence interval (CI): 0.036-0.20] with estimates of 0.049 (95% CI: 0.007-0.16) for Hodgkin lymphoma, 0.27 (95% CI: 0.054-1.44) for testicular cancer and 0.096 (95% CI: -0.002-0.39) for cervical cancer (P homogeneity = 0.25). The EOR/Gy increased with time since exposure (P trend = 0.004), with an EOR/Gy of 0.38 (95% CI: 0.12-1.04) for stomach cancer occurring ≥20 years postirradiation corresponding to odds ratios of 4.8 and 10.5 at radiation doses to the stomach of 10 and 25 Gy, respectively. Of 111 stomach cancers occurring ≥20 years after radiotherapy, 63.8 (57%) could be attributed to radiotherapy. Our findings differ from those based on Japanese atomic-bomb survivors, where the overall EOR/Gy was higher and where there was no evidence of an increase with time since exposure. By pooling data from three studies, we demonstrated a clear increase in stomach cancer risk over a wide range of doses from fractionated radiotherapy with the highest risks occurring many years after exposure. These findings highlight the need to directly evaluate the health effects of high-dose fractionated radiotherapy rather than relying on the data of persons exposed at low and moderate acute doses.

Thrombectomy in acute ischemic stroke: estimations of increasing demands.

BACKGROUND: New recommendations for mechanical thrombectomy in acute ischemic stroke suggest that thrombectomy should be considered for eligible patients with a large artery occlusion in the anterior circulation within 6 hours of stroke onset. The resources are unevenly spread and, in order to be able to meet a potentially increased demand, we have estimated the future need for thrombectomy. METHODS: The new treatment recommendations are similar to those that have been in use at the Karolinska University Hospital since 2007. Using our local thrombectomy data (2009-2011), we calculated the proportion of thrombectomies performed at our hospital by level of stroke severity according to the National Institutes of Health Stroke Scale score (0-5, 6-11, 12-19, and 20-35). We then estimated the total number of potential thrombectomies expected in Sweden by extrapolating our treatment proportions to the rest of Sweden through the use of data from the Swedish National Stroke Registry. RESULTS: The number of potential thrombectomies would have been more than five times higher (1268 estimated compared with 232 actually reported in the National Stroke Registry) if the new recommendations for thrombectomy in acute ischemic stroke had been implemented in 2013 (the year from which we had the most recent available data from the Swedish Stroke Registry). CONCLUSIONS: When the new recommendations are implemented broadly, there may be a substantial increase in demand for thrombectomies. Our study highlights the need for policymakers and healthcare professionals to prepare for the increasing demands for advanced endovascular stroke treatment.

Increased pancreatic cancer risk following radiotherapy for testicular cancer.

BACKGROUND: Pancreatic cancer risk is elevated among testicular cancer (TC) survivors. However, the roles of specific treatments are unclear. METHODS: Among 23 982 5-year TC survivors diagnosed during 1947-1991, doses from radiotherapy to the pancreas were estimated for 80 pancreatic cancer patients and 145 matched controls. Chemotherapy details were recorded. Logistic regression was used to estimate odds ratios (ORs). RESULTS: Cumulative incidence of second primary pancreatic cancer was 1.1% at 30 years after TC diagnosis. Radiotherapy (72 (90%) cases and 115 (80%) controls) was associated with a 2.9-fold (95% confidence interval (CI) 1.0-7.8) increased risk. The OR increased linearly by 0.12 per Gy to the pancreas (P-trend<0.001), with an OR of 4.6 (95% CI 1.9-11.0) for ⩾25 Gy vs <25 Gy. Radiation-related risks remained elevated ⩾20 years after TC diagnosis (P=0.020). The risk increased with the number of cycles of chemotherapy with alkylating or platinum agents (P=0.057), although only one case was exposed to platinum. CONCLUSIONS: A dose-response relationship exists between radiation to the pancreas and subsequent cancer risk, and persists for over 20 years. These excesses, although small, should be considered when radiotherapy with exposure to the pancreas is considered for newly diagnosed patients. Additional data are needed on the role of chemotherapy.

EPI-CT: design, challenges and epidemiological methods of an international study on cancer risk after paediatric and young adult CT.

Computed tomography (CT) has great clinical utility and its usage has increased dramatically over the years. Concerns have been raised, however, about health impacts of ionising radiation exposure from CTs, particularly in children, who have a higher risk for some radiation induced diseases. Direct estimation of the health impact of these exposures is needed, but the conduct of epidemiological studies of paediatric CT populations poses a number of challenges which, if not addressed, could invalidate the results. The aim of the present paper is to review the main challenges of a study on the health impact of paediatric CTs and how the protocol of the European collaborative study EPI-CT, coordinated by the International Agency for Research on Cancer (IARC), is designed to address them. The study, based on a common protocol, is being conducted in Belgium, Denmark, France, Germany, the Netherlands, Norway, Spain, Sweden and the United Kingdom and it has recruited over one million patients suitable for long-term prospective follow-up. Cohort accrual relies on records of participating hospital radiology departments. Basic demographic information and technical data on the CT procedure needed to estimate organ doses are being abstracted and passive follow-up is being conducted by linkage to population-based cancer and mortality registries. The main issues which may affect the validity of study results include missing doses from other radiological procedures, missing CTs, confounding by CT indication and socioeconomic status and dose reconstruction. Sub-studies are underway to evaluate their potential impact. By focusing on the issues which challenge the validity of risk estimates from CT exposures, EPI-CT will be able to address limitations of previous CT studies, thus providing reliable estimates of risk of solid tumours and leukaemia from paediatric CT exposures and scientific bases for the optimisation of paediatric CT protocols and patient protection.

Stomach cancer risk after treatment for hodgkin lymphoma.

PURPOSE: Treatment-related stomach cancer is an important cause of morbidity and mortality among the growing number of Hodgkin lymphoma (HL) survivors, but risks associated with specific HL treatments are unclear. PATIENTS AND METHODS: We conducted an international case-control study of stomach cancer nested in a cohort of 19,882 HL survivors diagnosed from 1953 to 2003, including 89 cases and 190 matched controls. For each patient, we quantified cumulative doses of specific alkylating agents (AAs) and reconstructed radiation dose to the stomach tumor location. RESULTS: Stomach cancer risk increased with increasing radiation dose to the stomach (Ptrend < .001) and with increasing number of AA-containing chemotherapy cycles (Ptrend = .02). Patients who received both radiation to the stomach ≥ 25 Gy and high-dose procarbazine (≥ 5,600 mg/m(2)) had strikingly elevated stomach cancer risk (25 cases, two controls; odds ratio [OR], 77.5; 95% CI, 14.7 to 1452) compared with those who received radiation < 25 Gy and procarbazine < 5,600 mg/m(2) (Pinteraction < .001). Risk was also elevated (OR, 2.8; 95% CI, 1.3 to 6.4) among patients who received radiation to the stomach ≥ 25 Gy but procarbazine < 5,600 mg/m(2); however, no procarbazine-related risk was evident with radiation < 25 Gy. Treatment with dacarbazine also increased stomach cancer risk (12 cases, nine controls; OR, 8.8; 95% CI, 2.1 to 46.6), after adjustment for radiation and procarbazine doses. CONCLUSION: Patients with HL who received subdiaphragmatic radiotherapy had dose-dependent increased risk of stomach cancer, with marked risks for patients who also received chemotherapy containing high-dose procarbazine. For current patients, risks and benefits of exposure to both procarbazine and subdiaphragmatic radiotherapy should be weighed carefully. For patients treated previously, GI symptoms should be evaluated promptly.

Radiation dose and subsequent risk for stomach cancer in long-term survivors of cervical cancer.

PURPOSE: To assess the dose-response relationship for stomach cancer after radiation therapy for cervical cancer. METHODS AND MATERIALS: We 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). RESULTS: More 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). CONCLUSIONS: Our findings show for the first time a significant linear dose-response relationship for risk of stomach cancer in long-term survivors of cervical cancer.

Mechanical thrombectomy as the primary treatment for acute basilar artery occlusion: experience from 5 years of practice.

BACKGROUND: Most studies of the treatment for acute basilar occlusion focus on intravenous or intra-arterial thrombolysis whereas data on mechanical thrombectomy as the preferred treatment for acute basilar occlusion are scarce. In this study, data are presented on 28 patients treated with mechanical thrombectomy as the preferred treatment for basilar artery occlusion. METHODS: Retrospective study comprising all patients who were treated for acute basilar occlusion at the Karolinska University Hospital from September 2005 to November 2010. Favorable outcome was defined as a modified Rankin score of ≤2 at 3-8 months after thrombectomy. RESULTS: Of 28 patients treated with mechanical thrombectomy, the proportion reaching a favorable outcome was 57% (95% CI 37% to 75%), and if there were no signs of acute infarction prior to treatment the proportion was 73% (95% CI 50% to 89%). Only 21% died (95% CI 8% to 41%). CONCLUSIONS: The results for mechanical thrombectomy for basilar artery occlusion were superior to those presented previously for intravenous and intra-arterial thrombolysis. The study suggests that mechanical thrombectomy is a method distinct from therapies based on thrombolysis and that any randomized clinical trial on treatment for acute basilar occlusion must consider mechanical thrombectomy as a separate entity.

Anterior dynamic ultrasound of the infant hip: evaluation of investigator dependence.

BACKGROUND: Anterior dynamic ultrasound of the infant hip has been shown to be a valuable tool for detection of developmental dysplasia of the infant hip, but to what extent the results from this method depends on the investigator is unknown. PURPOSE: To study to what extent the proportion of positive findings at anterior dynamic ultrasound investigation of infant hips varies with the observer. MATERIAL AND METHODS: Information on all ultrasound investigations of infant hips at a county hospital between January 2004 and August 2007 was evaluated. Proportion of findings for different investigators were calculated and in a multivariable logistic regression analysis, risk of treatment by investigating orthopedic surgeon and radiologist were adjusted for each other as well as for calendar period and infant sex. RESULTS: There was a striking variation in proportion of positive findings depending on the investigator. The proportion of infants treated varied with orthopedic surgeon from 4.2 to 53.9% (95% CI: 2.27 to 7.13 and 43.0 to 64.6, respectively) and the corresponding variation for radiologists ranged from 7.4 (95% CI: 4.29 to 11.8) to 23.9% (95% CI: 17.2 to 31.8). In the adjusted analysis, variation between different investigators remained essentially unaltered. CONCLUSION: Although the true proportions of positive findings in our study are unknown, our findings are unlikely to be explained by selection bias or chance. Thus, our study suggests that anterior dynamic ultrasound of the infant hip is highly dependent on the investigator and further studies of the implications of our results are warranted.

Second cancers after squamous cell carcinoma and adenocarcinoma of the cervix.

PURPOSE: Although 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. PATIENTS AND METHODS: We 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). RESULTS: Overall 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-Hodgkin's lymphoma were significantly higher among cervical AC than SCC survivors. CONCLUSION: The 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.

Gestational hypertension, preeclampsia, and risk of testicular cancer.

Altered levels of pregnancy hormones have been suggested to initiate testicular cancer prenatally in the male fetus. The placenta is the main source of pregnancy hormones, and pregnancy hypertension and preeclampsia are associated with placental malfunction, including altered levels of hormones such as estrogen and human chorionic gonadotropin. We therefore evaluated fetal exposure to pregnancy hypertension and preeclampsia in relation to risk of testicular cancer in adolescent and adult life. We identified 293 cases of germ cell testicular cancer in the Swedish Cancer Register, and 861 controls in the Swedish Medical Birth Register. The standardized antenatal and delivery charts of the cases and controls were traced in the archives of the delivery units, and information about maternal and pregnancy characteristics such as gestational hypertension, proteinuria, anemia, and glucosuria were extracted. Odds ratios (OR) with 95% confidence intervals (CI) were calculated using conditional logistic regression. We found a strongly decreased risk of testicular cancer among subjects exposed to severe gestational hypertension (OR, 0.29; 95% CI, 0.12-0.74, compared with no hypertension), whereas the risk was increased among those exposed to mild gestational hypertension (OR, 1.62; 95% CI, 0.98-2.69) during the fetal period. The mechanism behind the association between pregnancy hypertension and testicular cancer is unclear, but our findings may reflect a potentially protective effect of the altered pregnancy hormones such as human chorionic gonadotropin that occur in severe gestational hypertension and preeclampsia.

Risk of leukemia among survivors of testicular cancer: a population-based study of 42,722 patients.

PURPOSE: The aim of this study is to quantify excess absolute risk (EAR) and excess relative risk (ERR) of secondary leukemia among a large population-based group of testicular cancer survivors. METHODS: We identified 42,722 1-year survivors of testicular cancer within 14 population-based cancer registries in Europe and North America (1943-2002). Poisson regression analysis was used to model EAR (per 100,000 person-years [PY]) and ERR of secondary leukemia. Cumulative risks were calculated using a competing risk model. RESULTS: Secondary leukemia developed in 89 patients (EAR = 10.8 per 100,000 PY, 95% confidence interval [CI] = 7.6-14.6; ERR = 1.6, 95%CI = 1.0-2.2). Statistically significantly elevated risks were observed for acute myeloid leukemia (AML) (EAR = 7.2, 95%CI = 4.7-10.2) and acute lymphoblastic leukemia (EAR = 1.3, 95%CI = 0.4-2.8). In multivariate analyses, AML risk was higher among patients whose initial management included chemotherapy compared to those receiving radiotherapy alone (p = 0.1). Excess cumulative leukemia risk was approximately 0.23% by 30 years after testicular cancer diagnosis. CONCLUSIONS: Although ERR of leukemia following testicular cancer is large, EAR and cumulative risk, which are better gauges of the population burden, are small.

Second cancers among 104,760 survivors of cervical cancer: evaluation of long-term risk.

BACKGROUND: Given the extended survival of patients diagnosed with cervical cancer, the large number of these women treated with radiotherapy, and the presence in this population of established cancer risk factors such as human papillomavirus (HPV) infection and cigarette smoking, it is important to clarify long-term trends in second cancer risk. METHODS: Using data from 104,760 one-year survivors of cervical cancer reported to 13 population-based cancer registries in Denmark, Finland, Norway, Sweden, and the United States, we calculated standardized incidence ratios (SIRs) for second cancers overall and cancers at particular sites among women with cervical cancer, including cervical cancer patients who were treated or not treated with radiation, over more than 40 years of follow-up. Cox regression models were used to assess the time-varying association of radiotherapy with risk of second cancers and to assess the interaction of radiation treatment with age at diagnosis. All statistical tests were two-sided. RESULTS: Among 104,760 one-year survivors of cervical cancer, the risk of all second cancers taken together was increased to a statistically significant extent (n = 12,496; SIR = 1.30; 95% confidence interval [CI] = 1.28 to 1.33). Compared with the general population, in both radiotherapy (N = 52,613) and no-radiotherapy groups (N = 27,382), risks for HPV-related cancers (of the pharynx, genital sites, and rectum/anus) and smoking-related cancers (of the pharynx, trachea/bronchus/lung, pancreas, and urinary bladder) were elevated to a statistically significant extent. Cervical cancer patients treated with radiotherapy, but not those who did not receive radiotherapy, were at increased risk for all second cancers and cancers at heavily irradiated sites (colon, rectum/anus, urinary bladder, ovary, and genital sites) beyond 40 years of follow-up compared with women in the general population. The association of radiotherapy with second cancer risk was modified by age at cervical cancer diagnosis for rectum/anus, genital sites, and urinary bladder, with higher hazard ratios for second cancer at younger ages of cervical cancer. After adjustment for competing mortality, the 40-year cumulative risk of any second cancer was higher among women diagnosed with cervical cancer before age 50 (22.2%; 95% CI = 21.5% to 22.8%) than among women diagnosed after age 50 (16.4%; 95% CI = 16.1% to 16.9%). CONCLUSION: Cervical cancer patients treated with radiotherapy are at increased risk of second cancers at sites in close proximity to the cervix beyond 40 years of follow-up.

Age at surgery for undescended testis and risk of testicular cancer.

BACKGROUND: Undescended testis, which is a risk factor for testicular cancer, is usually treated surgically, but whether the age at treatment has any effect on the risk is unclear. We studied the relation between the age at treatment for undescended testis and the risk of testicular cancer. METHODS: We identified men who underwent orchiopexy for undescended testis in Sweden between 1964 and 1999. Cohort subjects were identified in the Swedish Hospital Discharge Register and followed for the occurrence of testicular cancer through the Swedish Cancer Registry. Vital statistics and data on migration status were taken from the Register of Population and Population Changes for the years 1965 through 2000. We estimated the relative risk of testicular cancer using Poisson regression of standardized incidence ratios, comparing the risk in the cohort with that in the general population. We also analyzed the data by means of Cox regression, using internal comparison groups. RESULTS: The cohort consisted of 16,983 men who were surgically treated for undescended testis and followed for a total of 209,984 person-years. We identified 56 cases of testicular cancer during follow-up. The relative risk of testicular cancer among those who underwent orchiopexy before reaching 13 years of age was 2.23 (95% confidence interval [CI], 1.58 to 3.06), as compared with the Swedish general population; for those treated at 13 years of age or older, the relative risk was 5.40 (95% CI, 3.20 to 8.53). The effect of age at orchiopexy on the risk of testicular cancer was similar in comparisons within the cohort. CONCLUSIONS: Treatment for undescended testis before puberty decreases the risk of testicular cancer.

Noncancer causes of death in survivors of testicular cancer.

BACKGROUND: Although modern treatments for testicular cancer are associated with increased survival, the long-term health effects of these treatments are unclear. We conducted a population-based study to quantify the long-term risks of mortality from noncancer causes among men with testicular cancer. METHODS: We identified 38,907 one-year survivors of testicular cancer within 14 population-based cancer registries in North America and Europe (from 1943 through 2002). We used data from these registries to calculate standardized mortality ratios (SMRs) for noncancer deaths and to evaluate associations between histology, age at testicular cancer diagnosis, calendar year of diagnosis, and initial treatment and the risk of noncancer mortality. All statistical tests were two-sided. RESULTS: A total of 2942 deaths from all noncancer causes were reported after a median follow-up of 10 years, exceeding the expected number of deaths from all noncancer causes in the general population by 6% (SMR = 1.06, 95% confidence interval [CI] = 1.02 to 1.10); the noncancer standardized mortality ratios did not differ statistically significantly between patients diagnosed before and after 1975, when cisplatin-based chemotherapy came into widespread use. Compared with the general population, testicular cancer survivors had higher mortality from infections (SMR = 1.28, 95% CI = 1.12 to 1.47) and from digestive diseases (SMR = 1.44, 95% CI = 1.26 to 1.64). Mortality from all circulatory diseases was statistically significantly elevated in men diagnosed with testicular cancer before age 35 years (1.23, 95% CI = 1.09 to 1.39) but not in men diagnosed at older ages (SMR = 0.94; 95% CI = 0.89 to 1.00). Men treated with chemotherapy (with or without radiotherapy) in 1975 or later had higher mortality from all noncancer causes (SMR = 1.34, 95% CI = 1.15 to 1.55), all circulatory diseases (SMR = 1.58, 95% CI = 1.25 to 2.01), all infections (SMR = 2.48, 95% CI = 1.70 to 3.50), and all respiratory diseases (SMR = 2.53, 95% CI = 1.26 to 4.53). Testicular cancer patients who were younger than 35 years at diagnosis and were treated with radiotherapy alone in 1975 or later had higher mortality from all circulatory diseases (SMR = 1.70, 95% CI = 1.21 to 2.31) compared with the general population. CONCLUSION: Men who have survived for at least 1 year after being diagnosed with testicular cancer have a slightly higher risk of dying from noncancer causes, including infections, digestive diseases, and circulatory diseases, than the general population. Men treated with chemotherapy in 1975 or later may be at particularly high risk.

Long-term solid cancer risk among 5-year survivors of Hodgkin's lymphoma.

PURPOSE: Hodgkin's lymphoma (HL) survivors are known to be at substantially increased risk of solid cancers (SC). However, no investigation has used multivariate modeling to estimate the relative risk (RR), excess absolute risk (EAR), and cumulative incidence for specific attained ages and ages at HL diagnosis. PATIENTS AND METHODS: We identified 18,862 5-year HL survivors from 13 population-based cancer registries in North America and Europe. Poisson regression was used to evaluate the effects of age at diagnosis, attained age, latency, sex, treatment, and year of diagnosis on the RR and EAR of SC. RESULTS: Among 1,490 identified SC, 850 were estimated to be in excess. For most cancer sites, both RR and EAR decreased with age at HL diagnosis and showed strong dependencies on attained age. For a patient diagnosed at age 30 years and survived to > or = 40 years, modeled risks were significantly elevated for cancers of the breast (RR = 6.1), other supradiaphragmatic sites (RR = 6.0), and infradiaphragmatic sites (RR = 3.7); the largest RR (20-fold) was observed for malignant mesothelioma. Thirty-year cumulative risks of SC for men and women diagnosed at 30 years were 18% and 26%, respectively, compared with 7% and 9%, respectively, in the general population. For young HL patients, risks of breast and colorectal cancers were elevated 10 to 25 years before the age when routine screening would be recommended in the general population. CONCLUSION: Multivariable modeling demonstrates for the first time temporal changes in SC risk not evident in unadjusted analyses, and can facilitate the development of individualized risk assessment and the creation of screening strategies for early detection.