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E Lynge

Publications and source records attributed to E Lynge.

At least 163 records · Page 9Linked to original sources
PubMed1987

Background and design of a Danish cohort study of workers in phenoxy herbicide manufacture.

In 1982, a Danish cohort study was initiated of workers in the manufacture of 2,4-dichlorophenol- and 4-chloro-ortho-cresol-based phenoxy herbicides, after a governmental working group had indicated the need for further data on the long-term health consequences of exposure to these phenoxy herbicides. A cohort study of workers in the manufacture of these substances was considered to be a valuable supplement to the Swedish case-control studies of patients exposed mainly in spraying. Manufacture of phenoxy herbicides was commenced in Denmark by Kemisk Vaerk Koege (KVK) in 1947, and this company has produced 2,4-D and MCPA, and later 2,4-DP and MCPP. Very limited amounts of 2,4,5-T have been processed in this plant, mainly in the formation of esters based on a purchased acid. Manufacture of MCPA was commenced by Esbjerg Kemikaliefabrik (EK) in 1951, and this production was later supplemented with 2,4-DP. Furthermore, MCPA was produced by Cheminova and Danske Gasvaerkers Tjaerekompagni for short periods in the late 1950s. All persons employed at KVK and EK from the time when these plants began operation, in 1933 and 1951 respectively, until 1982 were intended to be included in this cohort study. The registration was based on company records and, from 1964 onward, supplemented with data from a public pension scheme (ATP). Linkage of company records from KVK with ATP records for the overlapping period 1964-1980 showed 2,163 persons to be known in both datasets, whereas 614 persons were known only from the ATP records. The data collection has consequently shown that ATP provides a valuable data source for control of company records in Denmark. For the study period before 1964, the number of registered employees could be controlled by comparison with the number of employees reported by the companies on questionnaires for the national industrial statistics 1945-1969. In the analysis of this cohort study, special attention was given to soft tissue sarcomas and malignant lymphomas, which are the diagnostic groups associated with exposure to phenoxy herbicides in the Swedish case-control studies. Soft tissue sarcomas, in both organs and connective tissue, can be identified using the classifications found in the Danish Cancer Registry.

2,4-Dichlorophenoxyacetic Acid↗
PubMed1987

Use of public pension scheme and industrial statistics data for supplement of company records in Denmark and influence on cohort mortality pattern.

Completeness of company records is a crucial point in interpretation of follow-up studies of industrial cohorts. The Employers Quarterly Reports on Earnings (EQRE) are valuable for control of company records in the United States. The public Supplementary Pension Scheme (ATP) and the industrial statistics questionnaires are of equal value in Denmark. The authors report on a cohort study from a chemical plant, where cohort members were identified from company records, which were checked against ATP and industrial statistics data. The mortality analysis shows employees known only from the ATP data to have an excess mortality, relative risk (RR) = 1.45. Inclusion in the cohort of these additional employees only changed the relative risk in overall mortality from 1.01 to 1.04, but turned out to be decisive in the study of a rare disease.

Chemical Industry↗
PubMed1986

Incidence of cervical cancer following negative smear. A cohort study from Maribo County, Denmark.

In order to estimate the risk of developing cervical cancer among women who originally had cytologically normal Papanicolaou (Pap) smears, information has been collected on all Pap smears taken in Maribo County, Denmark in 1966-1982 among women born 1918-1952. A total of 27,811 women are included in the study, and cases of invasive cervical cancer developed in the study population have been identified from the local department of pathology and from the Danish Cancer Registry. The incidence of cervical cancer has been tabulated by number of previous negative smears and by time elapsed since last negative smear. Women with one previous negative smear have a zero risk of developing cervical cancer during the first year following the negative smear. The incidence among these women increases with length of time since the negative smear and reaches the level of unscreened women during the fifth year of follow-up. Women with 2-4 previous negative smears also have a negligible risk of developing cervical cancer during the first two years following the last negative smear. The incidence among these women increases less over time than the incidence for women with one previous negative smear. No cases of cervical cancer were observed among 7,716 women with 5+ previous negative smears. The study indicates that the 5-year risk of developing cervical cancer is 48% lower in women with one previous negative smear than in an unselected population of unscreened women. The 5-year risk for women with 2-4 previous negative smears is 69% lower than that for unscreened women.

Adult↗
PubMed1986

Silica dust and lung cancer: results from the Nordic occupational mortality and cancer incidence registers.

Autopsy studies of the relationship between silicosis and lung cancer have been mainly negative; but recent epidemiologic studies have indicated a positive association, and an excess lung cancer risk has been observed in some occupational groups with exposure to silica dust. For the further shedding of light on the possible association between silica dust and lung cancer, analysis was made on mortality and cancer incidence data available in census-based record linkage studies from the Nordic countries for males in occupational groups with potential exposure to silica dust. The study showed an excess lung cancer risk for foundry workers in all the Nordic countries and for miners in Sweden. These results were consistent with findings from previous in-depth epidemiologic studies. The lung cancer risk did not differ significantly from that of the respective national populations for males working in excavation; stone quarries; sand and gravel pits; and glass, porcelain, ceramic, and tile manufacture. Stonecutters, who are probably not exposed to known lung carcinogens at the workplace but in some places to high concentrations of silica dust, showed a significant excess lung cancer risk in both Finland and Denmark. Excess lung cancer risks furthermore were seen for Finish miners, for Finnish males in excavation work, and for Danish glassworkers.

Denmark↗
PubMed1986

Risk of cervical cancer following negative smears in Maribo County, Denmark, 1966-1982.

In order to estimate the risk of developing cervical cancer among women who had originally had cytologically normal smears, information has been collected on all smears taken in Maribo County, Denmark, in the years 1966-1982, among women born between 1918 and 1952. A total of 27,811 women are included in the study, and cases of invasive cervical cancer developing in the study population have been identified from the local department of pathology and from the National Cancer Registry. The incidence of cervical cancer has been tabulated by number of previous negative smears and by time elapsed since last negative smear. Women with one previous negative smear have a zero risk of developing cervical cancer during the first year following the negative smear. The incidence among these women increases with length of time since the negative smear and reaches the same level as that of unscreened women during the fifth year of follow-up. Women with two to four previous negative smears also have a negligible risk of developing cervical cancer during the first two years following the last negative smear. The incidence among these women increases less over time than the incidence for women with one previous negative smear. No case of cervical cancer was observed among 7716 women with five or more previous negative smears. The study indicates that the five-year risk of developing cervical cancer is 48% lower in women with one previous negative smear than in an unselected population of unscreened women. The five-year risk for women with two previous negative smears is 62% lower than that for unscreened women.

Adolescent↗
PubMed1985

A follow-up study of cancer incidence among workers in manufacture of phenoxy herbicides in Denmark.

The purpose of this cohort study is to shed further light on the potential carcinogenic effect indicated by a Swedish case control study of the 2,4-dichlorophenol and 4-chloro-ortho-cresol based phenoxy herbicides, unlikely to be contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). In the present study it was the intention to include all persons employed in manufacture of phenoxy herbicides in Denmark before 1982. The predominant product was MCPA and only a very limited amount of 2,4,5-T was processed in one of the two factories included in the study. Registration of the cohort was based on company records, supplemented with data from a public pension scheme from 1964 onwards. Ninety-nine percent of registered employees could be followed up. Cancer cases were identified by linkage with the National Cancer Register. Totals of 3,390 males and 1,069 females were included in the study. In the analysis special attention was given to soft tissue sarcomas (STS) and malignant lymphomas (ML) which are the diagnostic groups indicated to be associated with exposure to phenoxy herbicides in the Swedish studies. Five cases of STS were observed among male employees in contrast to 1.84 expected cases. This result supports the Swedish observation of an increased risk of STS following exposure to phenoxy herbicides unlikely to be contaminated with 2,3,7,8-TCDD. However, several potential biases have to be taken into account in interpretation of this observation and these are discussed. Seven cases of ML were observed among male employees in contrast to 5.37 expected which does not support the Swedish observation of an excess risk. The total cancer risk among persons employed in manufacture and packaging of phenoxy herbicides was equivalent to the cancer risk in the Danish population. Among males thus employed 11 lung cancer cases were observed in contrast to 5.33 expected. Attention should be given to exposure to spray dried MCPA-sodium salt in the plants, but other work place exposures and tobacco consumption may have contributed to the increased risk. The tabulation of data by many diagnostic groups may explain the excesses observed for rectum cancer among males and cervical cancer among females. The study has revealed that several potential biases have to be taken into account when the Swedish observations are tested in other settings.

Chemical Industry↗
PubMed1985

Cohort trends in incidence of cervical cancer in Denmark in relation to gonorrheal infection.

In England & Wales and in Scotland an association has been found between the cohort pattern in mortality for cervical cancer and gonorrheal infection, used as indicator of sexually transmitted diseases in general. An equivalent association could not be found in the United States. In Denmark a peak in gonorrheal infection was observed towards the end of World War II. The maximum level attained in Denmark was higher than reported from the other countries; in Copenhagen the attack rate was 3.3 times the rate for the rest of Denmark. Incidence data on cervical cancer in Denmark are available from 1943 to 1977. The 1918-27 birth cohort is assumed to be the one most heavily affected by the gonorrhea epidemic during the war. Incidence data accumulated over a broad age span show no general excess risk of cervical cancer for women born 1918-27, but the incidence is increased for this cohort 15-20 years after the gonorrheal infection. The cervical cancer rates are higher for women in Copenhagen than for all Danish women, but the excess risks for the affected cohorts are less systematic here. The limited size of the population in Copenhagen, migrations, and an intensive screening are possible explanations for the divergence between the results for all of Denmark and for Copenhagen. The study indicates an association in Denmark between sexually transmitted diseases and cervical cancer, and the study shows the importance of taking the risk-modifying effect of screening into account in studies of etiology for cervical cancer.

Adolescent↗
PubMed1985

Second cancer following cancer of the digestive system in Denmark, 1943-80.

Among 4,184 patients with cancer of the esophagus, 55 second primary cancers were observed, whereas 64 were expected [relative risk (RR) = 0.86]. The absence of an excess risk of alcohol- and tobacco-related cancers was not anticipated. A significant 19% deficit of second cancers was found among 30,843 patients with stomach cancer. Cancer of the rectum, kidney, and lung all occurred significantly below expectation. An excess risk of ovarian cancer (RR = 1.9) was seen in women. Reasons for these findings are not entirely clear. Cancer of the small intestine is rare, and despite a relatively short survival expectation, a moderate excess of second cancers was seen among 868 patients (36 vs. 26.8). Only cancers of the liver and gallbladder were significantly elevated, and the possibility of misclassified metastases is discussed. Colon cancer is one of the most common cancers in Denmark, and 29,490 patients with this disease were at slightly lower risk for development of second cancer (RR = 0.96; 95% confidence interval = 0.9-1.0) than the general Danish population, excluding secondary colon cancers. Esophageal, stomach, and liver cancers occurred less frequently than expected. That cancers of the uterine corpus and ovary were significantly increased supports the notion that common risk factors, such as diet and endogenous hormones, influence the development of these cancers. A significant 23% deficit of second cancers was also found among 26,597 patients with cancer of the rectum, excluding secondary rectal cancer. Significant deficits were seen for cancers of the stomach (RR = 0.5), lung (RR = 0.8), and brain (RR = 0.5), and for multiple myeloma (RR = 0.4). The likelihood of underreporting of second cancers, especially of the digestive system, is discussed. However, cancer of sites previously reported to be associated with rectal cancer, e.g., the colon, breast, and uterus, did not occur below expectation. Cancers of the liver and biliary tract occurred in 4,453 patients; their average survival was only 1 year. Except for a slight excess of cancer of the ovary (5 vs. 1.6), the risk of second cancer development for all sites was consistent with unity (RR = 0.90). The risk of second cancers among 7,752 persons with cancer of the pancreas was not greater than expected (88 vs. 85.2). Males were at significant risk of kidney cancer (RR = 3.2), whereas females showed elevated rates of cancers of the uterine corpus (RR = 3.2) and ovary (RR = 3.1). No site occurred significantly below expectation.

Colonic Neoplasms↗
PubMed1985

Second cancer following cutaneous melanoma and cancers of the brain, thyroid, connective tissue, bone, and eye in Denmark, 1943-80.

Second primary cancers were studied in persons with rare tumors between 1943 and 1980. The risk of developing a new cancer was evaluated in 7,211 persons with cutaneous melanoma, 1,784 persons with eye cancer, 10,273 persons with tumors of the brain and nervous system, 1,935 persons with thyroid cancer, 1,542 persons with bone tumors, and 2,318 persons with malignant neoplasms of the connective tissue. All cancer patients were diagnosed in Denmark between 1943 and 1980 and survived for 2 or more months. Nonmelanoma skin cancers were excluded from the analysis, whereas tumors of the brain and nervous system included both benign and malignant neoplasms. Overall, patients with these cancers showed no greater incidence of new tumors than expected from comparisons with the general population. An excess of chronic lymphocytic leukemia was observed subsequent to all cancers derived from the neural tube, i.e., melanoma and tumors of the eye, brain, and nervous system. Bone cancer occurred excessively, although the possibility of misclassified metastases could not be eliminated. Patients with tumors of the brain and nervous system who survived for 10 or more years developed significantly more cancers of the kidney and connective tissue and melanoma than anticipated. A deficit of second cancers of the digestive system was noted after primary bone and connective tissue cancers, in contrast to an excess of second cancers of the lung and kidney. Although based on few cases, patients with bone cancer showed a large excess of eye cancer as a second primary. The association between cancers of the breast and connective tissue was found to be bidirectional. Persons with connective tissue cancer were at increased risk of developing non-Hodgkin's lymphoma. Thyroid cancer patients were at high risk of subsequent tumors of the brain and nervous tissue and non-Hodgkin's lymphoma. However, contrary to previous reports, the risk of breast cancer was not elevated following thyroid cancer.

Bone Neoplasms↗
PubMed1985

Summary: multiple primary cancers in Denmark, 1943-80.

The risk of developing a second primary cancer was studied among 171,749 men and 208,192 women who were reported to the Danish Cancer Registry between 1943 and 1980. Only those who survived at least 2 months were included in the analysis, and more than 1.7 million person-years of observation were accrued. Altogether, 15,084 second primary cancers developed in organs other than the initial cancer site [relative risk (RR) = 0.99]. Adjustment for possible underreporting of multiple primary cancers increased the RR to 1.06. The overall RR of a second cancer developing for all sites was 0.91, but interpretation of this risk is difficult because new tumors arising within the same organ are generally not recorded in Denmark. The RR for all sites increased with time from 0.94 during the first decade of follow-up (excluding the first year) to 1.13 among 30-year survivors. Patients below the age of 20 years when first diagnosed with cancer experienced significantly increased risk of developing a second cancer. Elevated risks were also observed for sites thought to have a common etiology. For example, cancers of smoking-related sites were increased in both directions for cancers of the oral cavity, respiratory tract, and urinary organs. For cancers suspected to have a hormone- or dietary fat-related association, significant reciprocal relationships were seen among cancers of the endometrium, ovary, and colon. Cancer treatment probably is an important factor in second cancer development, even when judged indirectly in the present study. For example, radiotherapy may have been responsible for an elevated risk of subsequent cancers of the thyroid, breast, colon, rectum, bladder, connective tissue, and hematopoietic system in long-term survivors. Chemotherapy may have increased the risk of subsequent leukemias. Our data further indicate that cancer patients have no general susceptibility to develop new malignant tumors, although high rates may be found for particular sites sharing common risk factors. Conversely, the occurrence of one cancer does not appear to protect against developing a new cancer.

Adolescent↗
PubMed1984

The contribution of epidemiology to the study of occupational cancer.

Most chemical compounds and physical agents recognized as human carcinogens were first identified in the occupational environment by epidemiological studies. Some 2%-8% of all cancers have been attributed to occupational exposures, but the limitations of such estimates should be recognized. The use of existing medical information systems on occupational cancer for hypothesis generation may be improved by comparing the results emerging from different countries. An initiative in this direction is recommended. Clues emerging from such general systems should be submitted to further studies to test specific hypotheses concerning risk factors. Record linkage is necessary for the epidemiological study of occupational cancer. Efforts must be made towards the storage of identifiable records with information on occupation and cancer occurrence.

Canada↗