Biomedical subjects

Tapio Luostarinen

Publications and source records attributed to Tapio Luostarinen.

12 recordsLinked to original sources

PubMed2006

Enrolment of 22,000 adolescent women to cancer registry follow-up for long-term human papillomavirus vaccine efficacy: guarding against guessing.

Human papillomaviruses (HPVs, most notably types 16 and 18) cause cervical carcinoma, the second most common cancer among women. Vaccination of adolescents against HPV16/18 might prevent large proportion of cervical and other anogenital cancers. However, because of ethical reasons this cannot be proven by clinical studies. To determine the long-term vaccine efficacy (VE) of HPV16/18 virus-like-particle (VLP) vaccine against cervical carcinoma in situ (CIS+) and invasive cervical carcinoma, the following three population-based cohorts of adolescent women have been enrolled: (1) women vaccinated with the HPV vaccine; (2) women vaccinated with hepatitis A control vaccine; and (3) unvaccinated control women. These cohorts will be passively followed for cumulative incidence of CIS+ endpoints by population-based cancer registry. Overall 24,046 16- to 17-year-old adolescent women from 18 cities in Finland were invited between May 2004 and June 2005 to participate in a phase III trial with bivalent HPV16/18 VLP vaccine. A total of 58,996 18- to 19-year-old women were invited in May 2005 to participate as unvaccinated controls. Women who reported their willingness to participate in an HPV vaccination trial had they been 1-2 years younger were eligible. Cumulative incidence (CI) of CIS+ in our cohorts over 15 years is approximately 0.45%. VE of 70% against CIS+ with 80% power requires 3357-3189 HPV16/18 vaccine recipients, 3357-3189 other vaccine recipients, and 6714-9567 unvaccinated controls. We have now enrolled 2404 HPV16/18 vaccine recipients, 2404 hepatitis A-vaccine recipients, and 5130 unvaccinated controls. This enrolment in addition to our earlier enrolment in another phase III trial guarantees enough power so that by 2020 we can ultimately provide data on the efficacy of HPV16/18 vaccination against CIS+.

Adolescent↗

PubMed2005

A randomised public-health trial on automation-assisted screening for cervical cancer in Finland: performance with 470,000 invitations.

Our objective was to evaluate automation-assisted screening, in comparison to the conventional method, in a routine population-based cervical cancer-screening programme. Our study is based on an individually randomised design involving approximately 160,000 invitees and 110,000 attendees every year. From 1999 to 2001, 471,297 women were invited to attend and 330,445 smears were screened (attendance rate 70.1%), of which 220,254 were tested conventionally and 110,191 were tested using the automation-assisted method. Cytologic Papanicolaou group II findings were reported slightly more often (RR = 1.04) in the automation-assisted method than in the conventional screening arm. There were 1,291 cases of histologically confirmed dysplasia or carcinoma (0.4% of the screened), one-third of which were severe dysplasia or a more severe finding (CIN3+). The detection rates of histologically verified findings were similar between the 2 screening arms. In Finland, the screening programme has been effective. As the detection rates, particularly of CIN3+, were similar between the screening arms, we will continue the automation-assisted method in the routine screening programme. Further follow-up for interval cancer incidence is required, however, to measure if the effect of screening is the same between the arms. A similar evaluation design is feasible to any other major or competing modification of the screening test or other element in the programme.

Adult↗

PubMed2005

Maternal human polyomavirus infection and risk of neuroblastoma in the child.

To investigate if polyomavirus infection during pregnancy is linked to development of neuroblastoma in the child, serum samples of 115 index mothers from the pregnancy where the child eventually developed neuroblastoma were identified and matched with serum samples from 8 control mothers per index mother. The samples were tested for specific IgG and IgM antibodies to BK and JC virus using enzyme immunoassays based on purified yeast-expressed virus-like particles (VLPs). The serum samples as well as 10 neuroblastoma cell lines were also analyzed using Real Time (TaqMan) PCR for detection and quantification of BK virus DNA. The BK virus IgG seroprevalence was similar among index mothers (80%) and control mothers (83%) [OR 0.8; 95% confidence interval (95% CI): 0.5-1.3]. BK virus IgM was also not associated with neuroblastoma risk (OR was OR = 0.6; 95% with CI, 0.2-1.9). Also JC virus had no association, neither for IgG (OR = 0.9; 95% CI, 0.6-1.4) nor for IgM (OR = 0.9; 95% CI, 0.4-1.9). All serum samples and all neuroblastoma cell lines were negative for BKV DNA. In summary, a comprehensive cohort using both serology and polyomavirus DNA detection found no evidence for association between BKV or JCV polyomaviruses and neuroblastoma.

Adolescent↗

PubMed2005

Chlamydial antibodies and risk of prostate cancer.

OBJECTIVE: We assessed the risk of prostate cancer by exposure to Chlamydia trachomatis. METHOD: Seven hundred thirty eight cases of prostate cancer and 2,271 matched controls were identified from three serum sample banks in Finland, Norway, and Sweden by linkage to the population based cancer registries. RESULTS: A statistically significant inverse association (odds ratio, 0.69; 95% confidence interval, 0.51-0.94) was found. It was consistent by different serotypes and there was a consistent dose-response relationship. CONCLUSION: C. trachomatis infection is not likely to increase the risk of prostate cancer. Whether the inverse relationship is true or due to difficulties in measuring the true exposure in prostatic tissue by serology, confounders or other sources of error remain open.

Adult↗

PubMed2005

Human papillomavirus 16, 18, and 33 infections and risk of prostate cancer: a Nordic nested case-control study.

Epidemiologic evidence of sexual history has emerged as a consistently found risk factor for prostate cancer. Some studies have reported an association between human papillomavirus (HPV) infections and prostate cancer. We did a nested case-control study within cohorts of more than 200,000 men enrolled in three Nordic biobanking projects. Follow-up using cancer registry linkages identified 804 prospectively occurring prostate cancer cases. Four control subjects per case were randomly selected from eligible sets of matched subjects that were alive and free of cancer at the time of diagnosis of the corresponding case and were matched to cases on biobank cohort, age (+/-2 years), county of residence, and date of blood sampling (+/-2 months in the Finnish and Swedish cohorts, +/-6 months in the Norwegian cohort). The serum samples were analyzed by standard ELISAs for the presence of immunoglobulin G antibodies against HPV types 16, 18, and 33. The joint HPV-16/HPV-18/HPV-33 seroprevalence in the joint cohort was 13.4% (107 of 799) among cases and 14.0% (363 of 2,596) among controls (odds ratio, 0.94; 95% confidence interval, 0.74-1.19). There were no noteworthy differences when the data were analyzed by different HPV type, country, or antibody levels. Our data do not support an association between serologic markers of HPV-16, HPV-18, and HPV-33 infections and risk of prostate cancer.

Adult↗

PubMed2004

Survival of in situ carcinoma of cervix uteri: a 50-year follow-up in Finland.

Preinvasive lesions of cervix uteri are regarded a curable disease despite some progression to invasive cancer. The ultimate outcome is not known. We estimated the 45-year survival of 12,655 patients with carcinoma in situ lesions diagnosed in 1953-2000 and reported to the Finnish Cancer Registry. Up to 30 years of follow-up there was about 1% decrease in cumulative relative survival per 5 years of follow-up. After that the excess mortality increased and the survival at 45 years was 84%. The 15-year survival was 100% in the patients under 30 at diagnosis and became the poorer the older the patient. Survival was 89% in the patients 60-74 at diagnosis. Women with carcinoma in situ are at substantial increased risk of death (>10%) only at high ages and independent of age at diagnosis.

Adult↗

PubMed2004

High levels of circulating testosterone are not associated with increased prostate cancer risk: a pooled prospective study.

Androgens stimulate prostate cancer in vitro and in vivo. However, evidence from epidemiologic studies of an association between circulating levels of androgens and prostate cancer risk has been inconsistent. We investigated the association of serum levels of testosterone, the principal androgen in circulation, and sex hormone-binding globulin (SHBG) with risk in a case-control study nested in cohorts in Finland, Norway and Sweden of 708 men who were diagnosed with prostate cancer after blood collection and among 2,242 men who were not. In conditional logistic regression analyses, modest but significant decreases in risk were seen for increasing levels of total testosterone down to odds ratio for top vs. bottom quintile of 0.80 (95% CI = 0.59-1.06; p(trend) = 0.05); for SHBG, the corresponding odds ratio was 0.76 (95% CI = 0.57-1.01; p(trend) = 0.07). For free testosterone, calculated from total testosterone and SHBG, a bell-shaped risk pattern was seen with a decrease in odds ratio for top vs. bottom quintile of 0.82 (95% CI = 0.60-1.14; p(trend) = 0.44). No support was found for the hypothesis that high levels of circulating androgens within a physiologic range stimulate development and growth of prostate cancer.

Adult↗

PubMed2004

Both high and low levels of blood vitamin D are associated with a higher prostate cancer risk: a longitudinal, nested case-control study in the Nordic countries.

Vitamin D inhibits the development and growth of prostate cancer cells. Epidemiologic results on serum vitamin D levels and prostate cancer risk have, however, been inconsistent. We conducted a longitudinal nested case-control study on Nordic men (Norway, Finland and Sweden) using serum banks of 200,000 samples. We studied serum 25(OH)-vitamin D levels of 622 prostate cancer cases and 1,451 matched controls and found that both low (</=19 nmol/l) and high (>/=80 nmol/l) 25(OH)-vitamin D serum concentrations are associated with higher prostate cancer risk. The normal average serum concentration of 25(OH)-vitamin D (40-60 nmol/l) comprises the lowest risk of prostate cancer. The U-shaped risk of prostate cancer might be due to similar 1,25-dihydroxyvitamin D(3) availability within the prostate: low vitamin D serum concentration apparently leads to a low tissue concentration and to weakened mitotic control of target cells, whereas a high vitamin D level might lead to vitamin D resistance through increased inactivation by enhanced expression of 24-hydroxylase. It is recommended that vitamin D deficiency be supplemented, but too high vitamin D serum level might also enhance cancer development.

Adult↗

PubMed2003

Evaluation of antibody response to human papillomavirus early proteins in women in whom cervical cancer developed 1 to 20 years later.

OBJECTIVE: Infection with oncogenic human papillomaviruses (HPVs) is the most important cause of cervical cancer worldwide. After infection there is a long latency period of at least 10 to 15 years during which cervical cancer develops in a small proportion of originally infected women. Up to 50% of these women have at diagnosis antibodies to the HPV oncoproteins E6 and E7, which are rarely found among healthy women. Our purpose was to evaluate whether antibodies to HPV16 and HPV18 E6 and E7 proteins are useful for early diagnosis of cervical cancer by measuring the antibody response in women in whom cervical cancer later developed. STUDY DESIGN: A joint serum bank of 550,000 Swedish, Norwegian, and Finnish women was followed up for 0.5 to 20 years, after which 178 invasive cervical carcinoma (ICC) cases, 150 of whom had squamous cell carcinoma (SCC), and 527 controls were identified. Antibodies to HPV16 and HPV18 E6 and E7 proteins were determined by tag enzyme-linked immunoassays. RESULTS: HPV16/18 E6 and E7 antibodies were detected infrequently (7.0%) in women in whom SCC later developed and yielded a moderately increased estimate of associated relative risk (odds ratio 2.7, 95% CI 1.1-6.4). Sensitivity of the combined antibody tests for the detection of occult SCC varied between 6% and 14% but was not related to time lag between serum sampling and cancer diagnosis. CONCLUSION: HPV16/18 E6 and E7 antibody responses are not sensitive markers of occult cervical cancer.

Adult↗

PubMed2002

A population-based prospective study of Chlamydia trachomatis infection and cervical carcinoma.

Persistent human papillomavirus (HPV) infection is an established cause of cervical cancer, but the role of other sexually transmitted agents, most notably Chlamydia trachomatis, has not been well defined. The women participating in the population-based cervical cancer screening program in Västerbotten county of Northern Sweden were followed up for up to 26 years to identify 118 women who developed cervical cancer after having had a normal Pap smear (on average 5.6 years later; range 0.5 months-26 years). As controls, we selected another 118 women who were matched by birth cohort, time-point of sampling of the baseline normal smear and who had a normal smear at the time when the corresponding case was diagnosed with cancer. The Pap smears and cervical cancer biopsies were analyzed by PCR for C. trachomatis DNA and for HPV DNA. At baseline, C. trachomatis DNA was present in 8% of cases but not among any one of the controls. The relative risk for cervical cancer associated with past C. trachomatis infection, adjusted for concomitant HPV DNA positivity, was 17.1 (95% CI 2.6-infinity). The presence of C. trachomatis and of HPV were not interrelated. Whereas C. trachomatis was primarily found in specimens taken many years before cancer diagnosis, HPV DNA was associated with a short lag time before cancer diagnosis. Whereas most women who were HPV DNA-positive in the prediagnostic smear were also positive for the same virus in the cervical cancer biopsy, none of the women were positive for C. trachomatis in both the prediagnostic smear and in the subsequent cervical cancer. In conclusion, a prior cervical C. trachomatis infection was associated with an increased risk for development of invasive cervical cancer.

Adult↗

PubMed2002

Oral contraceptive use before first birth and risk of breast cancer: a case control study.

BACKGROUND: The aim of this study was first, to investigate whether women starting oral contraceptive (OC) use at a young age and before first birth have an increased risk for breast cancer and second, to report difficulties encountered in studying long-term health impacts of medical technologies. METHODS: Breast cancers occurring up until 1997 among 37153 Helsinki students born between 1946 and 1960 were identified by record linkage from the Finnish Cancer Registry; for each cancer case, five age-matched random controls were picked from the same student population. Those who had used the Helsinki Student Health Service (HSHS) at least three times (150 cases and 316 controls) form the final study subjects. Data on OC use and background characteristics were collected from patient records, and data on live births were derived from the population register. Odds ratios (OR) were adjusted for number of births, smoking and sports activity. RESULTS: Compared to the few non-users, OC users had a higher risk of breast cancer: the adjusted OR was 2.1 (95% confidence interval 1.1-4.2). Among OC users, no statistically significant differences in risk of breast cancer were found in regard to starting age or first birth, but small numbers made confidence intervals wide. Even though we had chosen students to be our study group, the population turned out to be unsuitable to answer our research question: most women had started their OC use old (at the age of 20 or later) and there were very few unexposed (almost all had used OC and before their first birth). CONCLUSIONS: Because adoption of the modern pattern of OC use was not common among students, it is unlikely that the impact of early and extended OC use can be studied before 2010, when women born in the 1960s are 40 to 50 years old.

Journal Article↗

PubMed2002

Circulating enterolactone and prostate cancer risk: a Nordic nested case-control study.

Enterolactone, a phytoestrogen belonging to the class of lignans, is produced by the intestinal microflora from precursors in plant foods and has been implicated in protection against cancer. We study the effect of enterolactone on the risk of a subsequent diagnosis of prostate cancer. We conducted a longitudinal, nested case-control study by linkage of 3 biobanks to the cancer registries in Finland, Norway and Sweden, respectively. Enterolactone concentrations were measured by time-resolved fluoroimmunoassay in serum from 794 men who had a diagnosis of prostate cancer at a mean follow-up time of 14.2 years after blood collection and among 2,550 control men matched within each cohort for age (+/-2 years), date of blood collection (+/-2 months) and county. The median enterolactone concentrations did not differ between case and control subjects in the full study group (8.4 nmol/L [25th-75th percentile = 4.5-15.0] vs. 8.5 nmol/L [25th-75th percentile = 4.3-15.9]), nor in the national groups. Odds ratios of prostate cancer risk estimated by conditional logistic regression for increasing concentrations of enterolactone in quartiles in the full study group were 1.00 (referent), 1.21 (95% confidence interval [CI] = 0.96-1.52), 1.16 (95% CI = 0.91-1.47) and 1.08 (95% CI = 0.83-1.39). The OR estimate for the highest vs. the lowest quartile of enterolactone in separate analyses of the Norwegian, Finnish and Swedish cohort was 1.21 (95% CI = 0.91-1.60), 1.02 (95% CI = 0.59-1.76) and 0.87 (95% CI = 0.45-1.67), respectively. No support for the hypothesis that high circulating enterolactone is protective against prostate cancer was found.

4-Butyrolactone↗