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T Hakulinen

Publications and source records attributed to T Hakulinen.

At least 19 recordsLinked to original sources
PubMed1999

No excess risk of cervical carcinoma among women seropositive for both HPV16 and HPV6/11.

Human papillomavirus (HPV) types 16 and 18 are the major risk factors for cervical carcinoma, whereas HPV types 6 and 11 cause benign genital lesions. We wanted to study the joint effect of simultaneous infections with the oncogenic and non-oncogenic HPV types on risk of subsequent development of cervical carcinoma. A cohort of 530,000 women who had donated blood samples to Nordic serum banks between 1973 and 1994 was followed up by linkage to national cancer registries. We identified 182 prospective cases with invasive cervical carcinoma and selected 538 matched controls at random. HPV 6, 11, 16, 18 and 33 seropositivity was used as a marker for the different HPV infections, and seropositivity for Chlamydia trachomatis and cotinine were used as markers for risk-taking sexual behavior and smoking respectively. The adjusted odds ratio (OR) of cervical squamous-cell carcinoma (SCC) was 2.2 for HPV6/11 among HPV16 seronegatives and 5.5 for HPV16 among HPV6/11 seronegatives. Assuming multiplicative joint effect, the expected OR for seropositivity to both HPV6/11 and HPV16 would have been 12, but the observed OR was 1.0. The antagonistic interaction was statistically significant (p = 0.001) and present also under deterministic considerations of possible misclassification bias. Antagonistic interactions were also detected for combinations of HPV16 and HPV18 and of HPV16 and HPV33. The results are in line with the concept that HPV-specific immunity protects against SCC and support primary prevention of SCC by vaccination against the HPVs.

Adult↗
PubMed1999

Risk of colorectal and other gastro-intestinal cancers after exposure to nitrate, nitrite and N-nitroso compounds: a follow-up study.

N-nitroso compounds are potent carcinogens detected in foodstuffs. The importance of dietary nitrosamines in relation to human cancer development is, however, uncertain. We studied the relationship between intake of nitrates, nitrites and N-nitrosodimethylamine (NDMA) and risk of cancers of the gastro-intestinal tract in a cohort of 9,985 adult Finnish men and women. During a follow-up period of up to 24 years, 189 gastro-intestinal cancer cases were diagnosed in the cohort, initially free from cancer. Intake of nitrate, nitrite and NDMA were estimated, based on food-consumption data from a 1-year dietary history interview covering the total diet of the participants. A significant positive association was observed between intake of NDMA and subsequent occurrence of colorectal cancer with a relative risk (RR) between the highest and lowest quartiles of intake of 2.12 [95% confidence interval (CI) 1.04-4.33]. Of various sources of N-nitroso compounds, intake of smoked and salted fish was significantly (RR = 2.58, 95% CI 1.21-5.51) and intake of cured meat was non-significantly (RR = 1.84, 95% CI 0.98-3.47) associated with risk of colorectal cancer. No similar association was observed for intake of other fish or other meat. No significant associations were observed between NDMA intake and cancers of the head and neck combined or of the stomach or between nitrate or nitrite intake and risk of cancers of the gastro-intestinal tract. Our results are in line with the idea that N-nitroso compounds can induce colorectal cancer in humans.

Adolescent↗
PubMed1999

Mixture models for cancer survival analysis: application to population-based data with covariates.

The interest in estimating the probability of cure has been increasing in cancer survival analysis as the curability of many cancer diseases is becoming a reality. Mixture survival models provide a way of modelling time to death when cure is possible, simultaneously estimating death hazard of fatal cases and the proportion of cured case. In this paper we propose an application of a parametric mixture model to relative survival rates of colon cancer patients from the Finnish population-based cancer registry, and including major survival determinants as explicative covariates. Disentangling survival into two different components greatly facilitates the analysis and the interpretation of the role of prognostic factors on survival patterns. For example, age plays a different role in determining, from one side, the probability of cure, and, from the other side, the life expectancy of fatal cases. The results support the hypothesis that observed survival trends are really due to a real prognostic gain for more recently diagnosed patients.

Age Factors↗
PubMed1999

Second primary cancers in patients with squamous cell carcinoma of the skin: a population-based study in Sweden.

We studied second primary cancer among 25,947 patients diagnosed with squamous cell carcinoma of the skin (SCC) in Sweden between 1958 and 1992. In total, 5,706 patients developed a second primary cancer at any site, compared with an expected number of 2,651 [standardized incidence ratio (SIR) = 2.15; 95% confidence interval (CI) = 2.10-2.21]. Men below 60 years of age at diagnosis of SCC had higher SIR (2.5; CI = 2.2-2.8) with the highest risk during the first year of follow-up (SIR = 9.2; CI = 6.9-12.2). If second primary SCC was excluded, the SIR was reduced to 1.30 (CI = 1.25-1.34); the relationships by sex, age and time since diagnosis remained similar. For skin cancer, the SIR for second SCC was markedly elevated (SIR = 15.6) and the risk of malignant melanoma was elevated 3-fold. Significantly increased risks were found for most second cancers in squamous cell epithelium: lip (SIR = 5.2), respiratory organs (SIR = 1.7), esophagus (SIR = 1.5), cervix uteri (SIR = 2.2), and vulva including vagina (SIR = 2.3). There was a generally increased risk of almost 2-fold for second cancer in hematopoietic or lymphoproliferative tissues. Slightly increased rates (SIR = 1.0-1.5) were seen for second tumors in digestive tissues. Finally, a high SIR (SIR = 5.5) was observed for second primary cancer in salivary glands. In conclusion, patients with SCC are at increased risk to develop new primary cancer, especially in skin, squamous cell epithelial and tobacco-related tissues. Common risk factors among the tumor types might explain our findings, however, an intrinsic susceptibility among SCC patients to develop cancer is also possible.

Age Distribution↗
PubMed1999

Methodological problems in comparing incidence and prevalence of leukaemias and lymphomas: ascertainment and age adjustment.

For a reliable incidence of a disease, all the cases that occurred in the area during the period of interest should be diagnosed, registered and classified correctly. It is very important to know in comparisons which data sources a particular cancer registry is utilizing and for how long it is waited until a publication of incidence is released. Examples from Finland show that deficits of up to 5-25% are possible in leukaemia and multiple myeloma. The populations to be compared may also have large differences in the age distribution. As the risk of all cancer, also for leukaemia and lymphomas, increases strongly by age, it is crucial that care is taken about the age adjustment before showing the incidence rates for comparisons. The age adjustment can be done using different methods and standards. In practice, the choice of methods for comparative purposes is often not crucial. It is also essential to evaluate the age-specific rates when making comparisons between populations. For cancer prevalence it would be important to know which patients can be considered cured. A population-based cancer registry does not, as a rule, have this information. However, if a cancer registry follows up the patients, survival rates of the patients may, after a number of follow-up years, start to resemble those in a comparable general population group. This is an indication that the living patients are cured and should be deducted from cancer prevalence. Advances would also be needed in statistical methods and improvement in the quality and coverage of cancer registration.

Adolescent↗
PubMed1999

Relationships between family dynamics of Finnish child-rearing families, factors causing strain and received support.

The aim of this study was to determine the relationships between family dynamics, the factors causing strain on child-rearing parents and the support available to families from public health nurses. Family dynamics was defined as the family's unique way of functioning and was conceptualized by means of six different dimensions. Questionnaires were sent to 118 families, and of these 85 mothers and 79 fathers participated in the study. According to the findings the majority of parents involved in bringing up children aged 3-4 years assessed their families to be well-functioning. There was a correlation between a low level of factors causing strain on the family and a positive evaluation of family dynamics based on the various dimensions. According to the mothers the support, i.e. emotional, appraisal and instrumental support, received from public health nurses, along with a small number of strain-causing factors on the partner relationship, correlated well with their positive assessments of the mutuality and flexibility of their families.

Adult↗
PubMed1999

Survival of cancer patients in Finland 1955-1994.

INTRODUCTION: The study of survival of cancer patients is essential for monitoring the effectiveness of cancer control. The previous monograph describing cancer patient survival in Finland was published by the Finnish Cancer Registry in 1981 and covered patients diagnosed in 1953-1974. This new supplement assesses cancer patient survival up to the year 1995. MATERIAL AND METHODS: The study includes over 560000 tumours registered at the Finnish Cancer Registry with a date of diagnosis between 1955 and 1994. Patients were followed up to the end of 1995. Trends in relative survival rates are studied over four 10-year diagnostic periods from 1955 to 1994. In addition, detailed results are presented for patients diagnosed during 1985-1994, including relative survival rates tabulated by stage, sex, and age. Additional sections describe differences in cancer patient survival according to social class and region of residence and a comparison of cancer patient survival in Finland to other European countries. RESULTS: Patient survival improved over time for almost all anatomical sites. The main exception is in cancer of the cervix uteri, where patient survival has decreased slightly from 1965-1974 to 1985-1994 due to the selective prevention of less aggressive tumours through cytologic screening. Very few differences in patient survival are observed between males and females. A substantial improvement in survival can be seen for childhood cancers. CONCLUSION: The increasing survival rates reflect improvements that have taken place in various areas of cancer control, from health education and early diagnosis to treatment and aftercare. This study provides valuable reference information for both clinicians and health administrators, as well as a baseline for more detailed studies of patient survival for individual anatomical sites.

Adolescent↗
PubMed1999

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↗
PubMed1998

Drinking water mutagenicity and urinary tract cancers: a population-based case-control study in Finland.

The detection of mutagenic and carcinogenic chlorination by-products in chlorinated drinking water has raised concern in many countries over the potential health effects of long-term exposure to these products. The relation between estimated exposure to historical drinking water mutagenicity and cancer was studied in Finland by using a population-based case-control study comprising 732 bladder cancer cases, 703 kidney cancer cases, and 914 controls. The cases were obtained from the nationwide Finnish Cancer Registry for the years 1991-1992. The controls, frequency matched by age and sex, were randomly selected from the national population registry. Information on past drinking water sources and confounding factors was acquired through a questionnaire. Historical exposure to drinking water mutagenicity was estimated by using information on past residence, past water source, and historical data on water quality and treatment. Odds ratios were calculated for an increase of 3,000 net revertants per liter (net rev/liter) in average exposure from 1950 to 1987, adjusting for age, sex, socioeconomic status, and smoking in logistic regression models. A small, statistically significant, exposure-related excess risk was found for kidney cancer for men (odds ratio = 1.49, 95 percent confidence interval (CI) 1.05-2.13) for 3,000 net rev/liter exposure level. For women, the association remained nonsignificant, with a lower odds ratio of 1.08 (95% CI 0.69-1.68). For bladder cancer, the odds ratio for both men and women was 1.22 (95% CI 0.92-1.62) for 3,000 net rev/liter exposure. However, a higher odds ratio of 2.59 (95% CI 1.13-5.94) for 3,000 net rev/liter exposure was observed for male nonsmokers.

Adult↗
PubMed1998

Variation in survival of adult patients with thyroid cancer in Europe. EUROCARE Working Group.

The survival of patients with thyroid cancer was analysed using population-based EUROCARE II data from 1978-1989 (trends in survival) and 1985-1989 (cross-sectional comparisons between areas). The data consisted of 7504 patients and covered 37 cancer registration areas in 17 European countries. In 90% of the patients the diagnosis was histologically confirmed. The prognosis of patients with thyroid cancer was relatively favourable. The overall 5-year relative survival rate was 72% for men and 80% for women. Substantial variation in this 5-year rate was observed between countries ranging from 59 to 83% in men and from 72 to 84% in women. Higher than average survival rates were observed in Finland, Iceland, The Netherlands and Sweden. Countries with lower than average rates were Denmark, England, Estonia, Slovakia, Slovenia and Poland (women). Elderly patients had lower survival rates than the younger ones. Time trends in survival (which could be analysed only in selected countries with sufficient numbers of cases) were irregular but generally showed slight increases compared with rates in 1978-1980. Different distributions in the histological subtypes of thyroid cancer is one plausible explanation for the variation in the survival rate. Other likely factors contributing to this are differences in the stage distribution and varying efficacy of treatment. The EUROCARE II data did not permit specific analyses of the roles of various prognostic factors.

Adenocarcinoma, Follicular↗
PubMed1998

Relationships between infant temperament, demographic variables, and family dynamics of childrearing families.

Relationships between infant temperament, demographic variables, and family dynamics of child-rearing families were investigated in this study. The revised Infant Temperament Questionnaire (RITQ), the Family Dynamics Questionnaire (FDQ) and the Family Dynamics Measure (FDM) were sent to 118 families who had participated in the first stage of the study as child-bearing families. About 8 months after childbirth 96 mothers and 95 fathers completed the questionnaires. The characteristics of infant temperament and demographic variables related to the variance of dimensions of family dynamics. Characteristics of the temperamentally easy baby related to more positive family dynamics perceived by child-rearing parents. Fathers rearing their first child reported that their families functioned better than fathers with their second infant. In child health clinics families rearing their second child should also be supported, especially families with arrhythmic and negative mood infants.

Adolescent↗
PubMed1998

Relative survival of cancer patients--a comparison between Denmark and the other Nordic countries.

The results of a Nordic collaborative project revealed that Danish cancer patients had a poorer prognosis than patients in the other Nordic countries for some major cancer sites. The present study was undertaken to further explore the differences in survival between Denmark and the other Nordic countries. All cancer cases diagnosed in the Nordic countries during 1958 to 1991/92 were included in the analysis. Relative survival and excess mortality were calculated for intervals in the first five years after diagnosis. Since the 1950s, the prognosis of cancer patients has improved in all the countries, but more moderately in Denmark. For cancers of the stomach, colon, rectum, breast (female), and prostate, the Danish patients had a markedly lower relative survival than the patients in the other countries. They also had the lowest proportion of localized tumours. It appears that Danish cancer patients are diagnosed at a later stage of disease than patients in the other Nordic countries.

Adolescent↗
PubMed1997

A simple non-linear model in incidence prediction.

A simple model is proposed for incidence prediction. The model is non-linear in parameters but linear in time, following models in environmental cancer epidemiology. Assuming a Poisson distribution for the age and period specific numbers of incident cases approximate confidence and prediction intervals are calculated. The major advantage of this model over current models is that age-specific predictions can be made with greater accuracy. The model also preserves in the period of prediction the age pattern of incidence rates existing in the data. It may be fitted with any package which includes an iteratively reweighted least squares algorithm, for example GLIM. Cancer incidence predictions for the Stockholm-Gotland Oncological Region in Sweden are presented as an example.

Adult↗
PubMed1997

A prospective, seroepidemiological study of the role of human papillomavirus in esophageal cancer in Norway.

Infection with the human papillomavirus (HPV), notably HPV type 16, has been associated with esophageal cancer in seroepidemiological studies. To evaluate the consistency of the association, we performed a nested case-control study of HPV seropositivity and risk of esophageal cancer within a prospectively followed cohort of 300,000 Norwegian men and women who had donated blood samples to a serum bank. The data file of the serum bank was linked with the nationwide Cancer Registry of Norway to identify esophageal cancers diagnosed after donation of the serum sample. Fifty-seven cases and 171 matched controls were analyzed for antibodies to specific microorganisms, and odds ratios for developing esophageal cancer were calculated. There was an increased risk of developing esophageal cancer among HPV 16-seropositive subjects (odds ratio = 6.6; 95% confidence interval, 1.1-71) but not among Chlamydia trachomatis-seropositive subjects. Adjustment for the presence of serum cotinine, a marker of smoking habits, did not affect the estimates substantially. The seroepidemiological association between HPV 16 and esophageal cancer seems to be consistent in different countries.

Adult↗
PubMed1997

Prospective seroepidemiological study of role of human papillomavirus in non-cervical anogenital cancers.

OBJECTIVE: To evaluate the association between infection with the major oncogenic types of human papillomavirus and the risk of developing non-cervical anogenital cancers in a cohort followed up prospectively. DESIGN: Data from two large serum banks to which about 700,000 people had donated serum samples were followed up for a mean of 8 years. People who developed non-cervical anogenital cancers during follow up were identified by registry linkage with the nationwide cancer registries in Finland and Norway. Within this cohort a nested case-control study was conducted based on the serological diagnosis of infection with human papillomavirus types 16, 18, and 33. SUBJECTS: 81 cases and 240 controls matched for sex, age, and storage time of serum samples. MAIN OUTCOME MEASURES: Odds ratios of developing non-cervical anogenital cancers in presence of IgG antibodies to specific micro-organisms. RESULTS: Subjects seropositive for human papillomavirus type 16 had an increased risk of developing non-cervical anogenital cancers (odds ratio 3.1 (95% confidence interval 1.4 to 6.9)). Subjects seropositive for type 33 also had an increased risk (odds ratio 2.8 (1.0 to 8.3)) but not significantly after adjustment for infection with type 16. Seropositivity for human papillomavirus type 16 was associated with an increased risk of developing vulvar and vaginal cancers (odds ratio 4.5 (1.1 to 22)) and a strongly increased risk of developing preinvasive vulvar and vaginal lesions (odds ratio infinity (3.8 to infinity)). Seropositivity for human papillomavirus type 18 increased the risk of developing preinvasive lesions (odds ratio 12 (1.2 to 590)). High, but non-significant odds ratios for types 16 and 33 were seen for penile cancers. CONCLUSIONS: This study provides prospective seroepidemiological evidence that infection with human papillomavirus type 16 confers an increased risk of developing non-cervical genital cancers, particularly vulvar and vaginal cancers.

Adult↗
PubMed1997

Prospective seroepidemiologic study of human papillomavirus infection as a risk factor for invasive cervical cancer.

BACKGROUND: Major risk factors for invasive cervical cancer include infection with human papillomavirus (HPV), infection with other sexually transmitted pathogens (e.g., Chlamydia trachomatis), and smoking. Since exposures to these risk factors can be related, the contribution of any single factor to cervical carcinogenesis has been difficult to assess. We conducted a prospective study to define the role of HPV infection in cervical carcinogenesis, with invasive cancer as an end point. METHODS: A nested case-control study within a joint cohort of 700,000 Nordic subjects was performed. The 182 women who developed invasive cervical cancer during a mean follow-up of 5 years were matched with 538 control women on the basis of age and time of enrollment. Serum samples taken at enrollment were analyzed for evidence of tobacco use (i.e., cotinine levels); for antibodies against HPV types 16, 18, and 33; and for antibodies against C. trachomatis. Relative risks (RRs) were estimated by use of conditional logistic regression. RESULTS: Presence of antibodies against HPV in serum (seropositivity) was associated with an increased risk of cervical cancer, and adjustment for smoking and for C. trachomatis seropositivity did not affect this finding (RR = 2.4; 95% confidence interval [CI] = 1.6-3.7). HPV16 seropositivity was associated primarily with an increased risk of squamous cell carcinoma (RR = 3.2; 95% CI = 1.7-6.2). In contrast, risk associated with HPV18 seropositivity tended to be higher for cervical adenocarcinoma (RR = 3.4; 95% CI = 0.8-14.9). In populations with a low prevalence of antibodies against C. trachomatis, the HPV16-associated risk of cervical cancer was very high (RR = 11.8; 95% CI = 3.7-37.0); in contrast, in populations with a high prevalence of antibodies against C. trachomatis, no excess risk was found. CONCLUSION: Past infection with HPV16 increases the risk of invasive cervical squamous cell carcinoma, most clearly seen in populations with a low prevalence of sexually transmitted diseases.

Adenocarcinoma↗