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H H Storm

Publications and source records attributed to H H Storm.

At least 19 recordsLinked to original sources

Cause-of-death registers in radiation-contaminated areas of the Russian Federation and Kazakhstan.

Since the early 1990s, information on radiation-exposed populations other than those exposed from the Chernobyl accident in 1986 has become increasingly available for international scientific research. It is essential to understand how the cohorts of exposed populations have been defined and what mechanisms can be used to study their health outcomes. Different international scientific research collaborations currently investigate four population groups chronically exposed to ionizing radiation during the late 1940s and early 1950s in the Russian Federation and in Kazakhstan. In this framework, collaborations have been established to develop cause-of-death registers in each of these four areas for future mortality follow-up purposes with the aim of studying the health effects of ionizing radiation. The emphasis of this effort is on assessing the information sources available, the mechanisms of data collection and coding, and the data quality and completeness of the information collected. One of the major challenges is the harmonization of all these aspects between the four different centers to the extent possible, taking into account that much of the actual data has been collected over many decades.

Cause of Death↗

Validity of breast cancer in the Danish Cancer Registry. A study based on clinical records from one county in Denmark.

Cancer registries are essential in order to monitor the incidence of cancer and, with proper follow-up, survival in a population. However, the usefulness of the registry depends upon the data quality. To validate the Danish Cancer Registry concerning breast cancer in female residents of Aarhus county 1983-1989, registry records were compared with clinical records. Completeness was validated in 2062 patients and correctness was determined for pathologically proven primary invasive breast cancer in 1949 patients. Incidence data were complete with no tumours missing. Data were coded according to ICD-7 and correctness of registry data in terms of basis of diagnosis and tumour malignancy was 99%. Information on extent of disease (stage) was not complete and there was a high disconcordance, in particular for bilateral breast tumours and cases with distant metastasis. Even crude staging into local and regional disease was inconsistent for 13% of cases, which probably hampered survival analysis by stage. The quality of registry data should be addressed when using variables, such as stage, not routinely reported by registries.

Adult↗

A reanalysis of liver cancer incidence in Danish patients administered thorotrast using a two-mutation carcinogenesis model.

In recent years, a two-mutation carcinogenesis (TMC) model has been used to analyze epidemiological data and estimate the radiation risks at low doses for the organs affected. Here the TMC model was used to reanalyze the liver cancer incidence in the Danish population in general and in patients administered Thorotrast, and to estimate the radiation risks for the liver. The data for 807 patients for whom sufficient data on the injected volumes of Thorotrast were available were used in this reanalysis. These data were combined with data on liver cancer incidence in the Danish population as the baseline or background incidence. Because males and females show different baseline liver cancer incidences, separate fits were made for males and females. The fits showed that the radiation effect could be ascribed entirely to the radiation dependence of the first mutation rate of the TMC model, which was higher for females than for males. The second mutation rate was not significantly dependent on dose. The radiation risks for the liver were calculated on the basis of the model parameters. These risks for lifetime exposures are about the same for males and females and are between a factor of 2 and 10 higher than current estimates. The discrepancy between the model results and previous risk estimates probably arises because the model calculations give more complete lifetime radiation risk estimates. For short-term exposures of the liver to ionizing radiation, the maximum radiation-induced excess liver cancer risk per unit dose applies to exposures at the age of about 10; exposures at ages above 35 have a radiation effect of less than approximately 15% of this maximum.

Adolescent↗

[Untreated breast cancer in Denmark 1978-1995].

INTRODUCTION: The lack of registration of women who have received no or alternative treatment for breast cancer has been criticised. No distinction is made in the Danish Cancer Register between these patients and those who only receive palliative treatment for other reasons, such as old age, advanced disease, and competing illnesses. We have estimated the number of women in this group of patients, who, in reality, had not received any treatment with the intent to cure under the health care system, and whether a meaningful analysis of survival for these patients is feasible. METHOD: All women with breast cancer diagnosed during the years 1978-1995 were extracted from the Cancer Register, and we isolated those who had been registered as having had no or only palliative treatment and who had survived for a minimum of 45 days after diagnosis. A search was made in the Danish Breast Cancer Co-operative Group register for unreported treatment and the residual group was followed up individually. RESULTS: Out of 49.058 women with histologically or cytologically verified breast cancer, the Cancer Register listed 840 women with no registered treatment of their disease. Of these, there were 103 cases of carcinoma in situ. A match with the DBCG register revealed that 188 women had nevertheless been operated on. Among the remaining 549 women, 99 were truly untreated, and for 77 of these the reasons given were another or advanced disease or old age. Only 22 women had initially declined treatment for no specific reason. Five of these had later decided on subsequent curative treatment, which leaves 17 women in the category "breast cancer untreated at her own request" ("untreated breast cancer at own will"). Nine are dead, five had their tumour excised at biopsy, and the remaining three are alive with tumours diagnosed by fine needle aspiration biopsy (1) or thru-cut biopsy (2) after 7.7 and 4 years, respectively. CONCLUSION: This report has shown that a survival analysis based on the Cancer Register of untreated breast cancer in relation to treated breast cancer is not meaningful. A true estimation of survival after untreated versus treated breast cancer can only be achieved through a randomised study, which would be unethical.

Age Factors↗

[Balkanitis].

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Bosnia and Herzegovina↗

Survival of children with thyroid cancer in Europe 1978--1989.

Thyroid cancers are rare in childhood with between 0.4 and 1.5 cases per million, 2--3 times as frequent in girls as in boys. However, following the Chernobyl accident, a remarkable incidence increase was observed in children exposed to radioactive iodine fall-out. Survival after thyroid cancer in childhood is thus of interest. In the EUROCARE II study, excluding most of Eastern Europe, a total of 165 childhood thyroid cancers were reported during the period 1978--1989, of which 134 were aged 10--14 years. The childhood cancer registry in England and Wales contributed 39% of the cases, and another 24% came from the Nordic countries, the rest from other parts of west, south, east and central Europe. The 5-year survival was for both genders combined 97% (95% confidence interval (CI): 93--99), 98% (95% CI: 91--100) for boys and 97% (95% CI: 91--99) for girls, with no significant difference between the genders. Survival was high during the entire study period, and variations influenced by the small numbers. As for adults, long-term follow-up beyond 10--20 years is needed to clearly demonstrate excess mortality as a consequence of the cancer.

Adolescent↗

Validity and completeness of registration of surgically treated malignant gynaecological diseases in the Danish National Hospital Registry.

BACKGROUND: The increasing tendency to acquire data by linkage to registries not designed for research has introduced a problem into epidemiological research. The data is often crude or possibly incomplete and, in some cases, it has been proposed to use these registries in the routine acquisition of data for existing epidemiological research registries. This study estimates the validity and completeness of the registration of surgically treated malignant gynaecological diseases in the Danish National Hospital Registry 1977-88. METHODS: Completeness was estimated by the method of independent case ascertainment, by comparison with the registration of surgically treated gynaecological cancer cases registered in the Danish Cancer Registry. The validity of the diagnoses was analysed by comparison with the recoding of discharge summaries describing the admission of a 5% random sample. RESULTS: The completeness of registration was 87% overall. Ovarian cancer, cervical cancer and cancer of the uterus were registered with a positive predictive value (PPV) of 89-90%. DISCUSSION: The results of the study emphasise the need to consider the validation of Danish Hospital Registry data before linkage and analysis. In epidemiological cancer research the Danish Cancer Registry is the better alternative when information on malignant tumours is needed.

Denmark↗

Mortality after cerebral angiography with or without radioactive Thorotrast: an international cohort of 3,143 two-year survivors.

There are few studies on the long-term sequelae of radionuclides ingested or injected into the human body. Patients exposed to radioactive Thorotrast in the 1930s through the early 1950s provide a singular opportunity, since the administration of this radiographic contrast agent resulted in continuous exposure to alpha particles throughout life at a low dose rate. We evaluated cause-specific mortality among an international cohort of 3,143 patients injected during cerebral angiography with either Thorotrast (n = 1,736) or a similar but nonradioactive agent (n = 1,407) and who survived 2 or more years. Standardized mortality ratios (SMRs) for Thorotrast and comparison patients were calculated, and relative risks (RR), adjusted for population, age and sex, were obtained by multivariate statistical modeling. Most patients were followed until death, with only 94 (5.4%) of the Thorotrast patients known to be alive at the closure of the study. All-cause mortality (n = 1,599 deaths) was significantly elevated among Thorotrast subjects [RR 1.7; 95% confidence interval (CI) 1.5-1.8]. Significantly increased relative risks were found for several categories, including cancer (RR 2.8), benign and unspecified tumors (RR 1.5), benign blood diseases (RR 7.1), and benign liver disorders (RR 6.5). Nonsignificant increases were seen for respiratory disease (RR 1.4) and other types of digestive disease (RR 1.6). The relative risk due to all causes increased steadily after angiography to reach a threefold RR at 40 or more years (P < 0.001). Excess cancer deaths were observed for each decade after Thorotrast injection, even after 50 years (SMR 8.6; P < 0.05). Increasing cumulative dose of radiation was directly associated with death due to all causes combined, cancer, respiratory disease, benign liver disease, and other types of digestive disease. Our study confirms the relationship between Thorotrast and increased mortality due to cancer, benign liver disease, and benign hematological disease, and suggests a possible relationship with respiratory disorders and other types of digestive disease. The cumulative excess risk of cancer death remained high up to 50 years after injection with >20 ml Thorotrast and approached 50%.

Adult↗

Risk of Hodgkin's disease and other cancers after infectious mononucleosis.

BACKGROUND: Infectious mononucleosis, which is caused by the Epstein-Barr virus, has been associated with an increased risk for Hodgkin's disease. Little is known, however, about how infectious mononucleosis affects long-term risk of Hodgkin's disease, how this risk varies with age at infectious mononucleosis diagnosis, or how the risk for Hodgkin's disease varies in different age groups. In addition, the general cancer profile among patients who have had infectious mononucleosis has been sparsely studied. METHODS: Population-based cohorts of infectious mononucleosis patients in Denmark and Sweden were followed for cancer occurrence. The ratio of observed-to-expected numbers of cancers (standardized incidence ratio [SIR]) served as a measure of the relative risk for cancer. SIRs of Hodgkin's disease in different subsets of patients were compared with the use of Poisson regression analysis. All statistical tests including the trend tests were two-sided. RESULTS: A total of 1381 cancers were observed during 689 619 person-years of follow-up among 38 562 infectious mononucleosis patients (SIR = 1. 03; 95% confidence interval [CI] = 0.98-1.09). Apart from Hodgkin's disease (SIR = 2.55; 95% CI = 1.87-3.40; n = 46), only skin cancers (SIR = 1.27; 95% CI = 1.13-1.43; n = 291) occurred in statistically significant excess. In contrast, the SIR for lung cancer was reduced (SIR = 0.71; 95% CI = 0.58-0.86; n = 102). The SIR for Hodgkin's disease remained elevated for up to two decades after the occurrence of infectious mononucleosis but decreased with time since diagnosis of infectious mononucleosis (P: for trend <.001). The SIR for Hodgkin's disease tended to increase with age at diagnosis of infectious mononucleosis (P: for trend =.05). Following infectious mononucleosis, the SIR for Hodgkin's disease at ages 15-34 years was 3.49 (95% CI = 2.46-4.81; n = 37), which was statistically significantly higher than the SIR for any other age group (P: for difference =.001). CONCLUSION: The increased risk of Hodgkin's disease after the occurrence of infectious mononucleosis appears to be a specific phenomenon.

Adolescent↗

Cancer risk in patients on dialysis and after renal transplantation.

The increased risk of cancer in patients who have had kidney transplants has mainly been attributed to immunosuppressive therapy; however, the prior period of uraemia and dialysis has also been postulated as a cofactor. We analysed cancer risk retrospectively in a cohort of 4178 patients undergoing renal replacement therapy, of whom 3592 were treated with dialysis alone and 1821 later had transplants. We found that excess cancer risk in such patients occurred after transplantation and not during dialysis.

Adult↗

Non-melanoma skin cancer may be a marker of poor prognosis in patients with non-Hodgkin's lymphoma.

According to recent results, patients with non-melanoma skin cancers are at increased risk of developing non-Hodgkin's lymphoma (NHL). The prognostic significance of this association is unknown. Two cohorts of patients with a first diagnosis of non-melanoma skin cancer and a subsequent diagnosis of either NHL (n = 170) or colon cancer (n = 435) were established using national cancer registry data in Denmark. Two other cohorts of patients in whom NHL (n = 600) or colon cancer (n = 1,541) was the patients' first known malignancy served as comparison groups. Mortality rates were compared using Cox's regression analysis. Among patients younger than 80 years at NHL diagnosis, a history of non-melanoma skin cancer was associated with significantly increased mortality [relative risk (RR) = 1.54; 95% confidence interval: 1.19-1.99]. This association was present in both men (RR = 1.38; 1.02-1.86) and women (RR = 2.15; 1.31-3.54) and was similar after both major subtypes of non-melanoma skin cancer. Overall, antedating non-melanoma skin cancer had no prognostic significance for colon cancer patients (RR = 1.00; 0.84-1.18). Whatever the underlying mechanism, our observation has potential clinical implications. If substantiated in other settings, NHL patients with prior non-melanoma skin cancer may constitute a subgroup of lymphoma patients in need of particular therapeutic attention.

Adult↗

Radiation-induced acute myeloid leukaemia and other cancers in commercial jet cockpit crew: a population-based cohort study.

BACKGROUND: Cockpit crews receive cosmic radiation during flight operations. The increasing total accumulated dose over the years might be expected to cause increased frequency of radiation-induced cancer. The rate should increase with number of flight hours per year, number of years of flying, and higher flight altitude. If the cumulative radiation exposure during flights is of concern, we would expect an increased cancer risk to be present among those crew members flying jets. METHODS: Cockpit-crew medical records (pilots and flight engineers) from 1946 onwards, holding information on the individual, flight hours, aircraft type, and date of commercial certification and decertification, were linked to the population-based Danish Cancer Registry, the central population registry, and the National Death Index. FINDINGS: Altogether 3877 cockpit crew members could be traced for follow-up, accruing 61095 person-years at risk in 3790 men and 661 in 87 women. The total number of cancers observed was 169 whereas 153.1 were expected (standardised incidence ratio 1.1 [95% CI 0.94-1.28]). Significantly increased risks of acute myeloid leukaemia (5.1 [1.03-14.91]), skin cancer, excluding melanoma (3.0 [2.12-4.23]), and total cancer (1.2 [1.00-1.53]) were observed among Danish male jet cockpit crew members flying more than 5000 h. Increased risk of malignant melanoma irrespective of aircraft type was also found among those flying more than 5000 h. INTERPRETATION: Both malignant melanoma and skin cancer were found in excess in cockpit crew members with a long flying history, probably attributable to sun exposure during leisure time at holiday destinations. We cannot confirm previously reported increased risk of brain and rectal cancers in pilots. The study shows that male cockpit crew members in jets flying more than 5000 h have significantly increased frequency of acute myeloid leukaemia.

Adolescent↗

Verapamil and risk of cancer in patients with coronary artery disease. DAVIT Study Group. Danish Verapamil Infarction Trial.

The risk of cancer in users of verapamil was assessed in a long-term follow-up of 1,775 patients who were randomized to verapamil or matching placebo in the Danish Verapamil Infarction Trial-II in the years 1985 to 1987. During 10,474 patient-years, no increased risk of cancer was observed for the verapamil-treated men or women compared with the age- and sex-matched background population.

Aged↗

Do morphology and stage explain the inferior lung cancer survival in Denmark?

Danish lung cancer patients diagnosed during 1983-1987 experienced 5-yr relative survival rates 2-7% inferior to patients in the other Nordic countries, despite the similarity of cancer registration and healthcare systems in the Nordic countries. Is the inferior relative survival in Denmark due to differences in morphology or stage of lung cancers? The present study compared in detail the survival of 92,719 patients diagnosed with lung cancer during 1978-1992 in Denmark, Finland, and Norway. In particular, differences in morphology and extent of disease were studied. A poor survival rate for small cell anaplastic lung carcinoma compared with all other morphologies was confirmed. However, this could not explain the relative survival differences observed between countries. Extent of disease was the most important predictor of survival. Part of the observed survival differences could be explained by a less favourable stage distribution in Denmark, combined with a slightly lower relative survival rate for those with metastatic disease. Differences in treatment are unlikely to explain the findings, although delays in diagnosing and treating patients in Denmark compared with neighbouring countries could partially explain the lower patient survival in Denmark. In conclusion, the main factor in the lower survival rate in Denmark is unfavourable stage distribution.

Aged↗

Colorectal cancer in the Faroe Islands--a setting for the study of the role of diet.

BACKGROUND: The Faroe Islands are a group of small islands in the north Atlantic. The population is well-defined and is therefore very suitable for epidemiological research, including dietary studies in relation to carcinogenesis. With the establishment of a cancer registry on January 1, 1994, with data from 1960, inspection of incidence rates and trends in cancer may give clues to areas for etiologic research. METHODS: We identified retrospectively all incident cases of colorectal cancer in the period 1979-1993, by reviewing all case reports and death certificates in the Faroe Islands. RESULTS: We found 242 cases of colorectal cancer: 166 colon cancers and 76 rectal cancer, of which 93% and 96% (respectively) were histologically confirmed. Colorectal cancer incidence was significantly lower than in Denmark, with standardised incidence ratios (SIRs) for colon cancer at 0.8 (95% CI = 0.7-1.0) in men and 0.7 (95% CI = 0.6-0.9) in women. For rectal cancer SIRs were 0.6 (95% CI = 0.5-0.9) in males and 0.6 (95% CI = 0.4-0.9) in females. CONCLUSIONS: This paper presents for the first time incidence rates of colorectal cancer in the Faroe Islands. For both cancer types the most recent standardised incidence rates, 1989-1993, were among the lowest in north western Europe and North America. This relatively low risk of colorectal cancer occurs in spite of a low intake of vegetables and a high intake of total fat. However, the Faroese diet is high in fish, calcium and vitamin D and the possibility therefore exist that the low rates are due to a protective effect of these nutrients and micronutrients.

Adult↗

[Cancer registration in the Faeroe Islands].

The main purpose was to establish a cancer registry which could provide data for the treatment and control of cancer in the Faroe Islands. The registry should also be useful for epidemiological research in the future to pinpoint causes of cancer. The initiation of the registry is a result of a workgroup with members from the Faroes Hospital and Health System and from the Institute of Cancer Epidemiology at the Danish Cancer Society. The data items collected in the Faroes registry are identical with the data items in the Danish Cancer Registry. To provide a basis for the registry we have performed a retrospective data collection identifying all cancer cases in the Faroes for the 15 year period 1979-1993. All hospital records and death certificates in the period were scrutinized. The official initiation of the Faroes cancer registry was on 1, January 1994.

Denmark↗