Matti Hakama

University of Tampere, Tammerfors, Pirkanmaa, Finland

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Publications (423)2061.79 Total impact

  • Suvi Mäklin · Matti Hakama · Pekka Rissanen · Nea Malila
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    ABSTRACT: Objective: To estimate the difference in use of hospital resources in the Finnish Colorectal Cancer (CRC) screening programme between those invited and controls, within the year of randomisation and the next year. Design: CRC screening was implemented in Finland in 2004 as a population-based randomised design using biennial faecal occult blood test (FOBT) for men and women aged 60-69 years. Those randomised to screening and control groups during years 2004-2009 were included in this analysis and use of hospital resources was estimated. Data were collected from the national register on hospital discharges. Outpatient visits, inpatient episodes and colonoscopies were compared between the two groups. Results: The screening group comprised of 123 149 and control group of 122 930 people. Most people in both groups had not used hospital resources at all. More people in the screening group than in the control group had at least one hospital-based outpatient visit (7.8% vs 7.4%), inpatient episode (3.9% vs 3.8%) and colonoscopy (1.5% vs 1.3%). In total, the screening group had 31 975 and control group 27 061 cumulative outpatient visits, 9260 and 7903 inpatient episodes, and 2686 and 1756 hospital colonoscopies, respectively. The proportion of those with a positive FOBT result with at least one outpatient visit, one inpatient episode or one colonoscopy, was 3.7 times, 2.5 times or 9 times that of those with a negative FOBT result, respectively. Conclusions: CRC screening using the FOBT slightly increased the volume of hospital outpatient visits, inpatient episodes and hospital colonoscopies in Finland.
    No preview · Article · Dec 2015
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    Full-text · Dataset · Dec 2015
  • K Seppä · J Pitkäniemi · N Malila · M Hakama
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    ABSTRACT: Objective: To assess whether age-related incidence of cervical cancer supports two aetiological components and to assess trends in these components due to risk factors and to organised screening in Finland. Design: Population-based register study. Setting: Finnish Cancer Registry. Population: Cervical cancer cases and female population in Finland in 1953-2012. Methods: Cervical cancer incidence was estimated using Poisson regression where age-specific incidence consists of two (early-age and late-age) normally distributed components. Main outcome measures: Accumulated net risks (incidences) and numbers of cancer cases attributed to each age-related component by calendar time. Results: The accumulated cervical cancer incidence in 2008-2012 was only 30% of that in 1953-1962, before the screening started. The fit of the observed age-specific rates and the rates based on the two-component model was good. In 1953-62, the accumulated net risk ratio (RR; early-age versus late-age) was 0.42 (95% CI 0.29-0.61). The early-age component disappeared in 1973-77 (RR 0.00; 95% CI 0.00-0.08). Thereafter, the risk for the early-age component increased, whereas the risk for the late-age component decreased, and in 2008-2012 the RR was 0.55 (95% CI 0.24-0.89). Conclusions: In Finland, cervical cancer incidence has two age-related components which are likely to indicate differences in risk factors of each component. The trend in risk of both components followed the effects of organised screening. Furthermore, the risk related to the early-age component followed changes in risk factors, such as oncogenic HPV infections and other sexually transmitted diseases and smoking habits. Tweetable abstract: Cervical cancer incidence has two age-related components which are likely to have differencies in their aetiology.
    No preview · Article · Nov 2015 · BJOG An International Journal of Obstetrics & Gynaecology
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    ABSTRACT: Background: Socioeconomic factors are associated with screening in terms of reducing the risk of cervical cancer. This study aimed to clearly establish the effect of screening on variation in socio-economic factor-specific survival estimates. Materials and methods: Survival estimates were calculated using the life table method for 165 women from the routine care control arm and 67 from the visual inspection with acetic acid screening arm diagnosed with cervical cancer during 2000-2006 in rural south India. Kaplan-Meier survival curves were plotted to compare the variation in survival by socioeconomic factors. Results: Whereas there was a significant variation in survival estimates of the different categories of age at diagnosis among the screen-detected cancers with women aged<50 years having an improved survival, no significant variation was noted among women diagnosed with cervical cancer from the control arm. Compared to the variation among the cancer cases detected in the unscreened control group, screening widened the variation in survival estimates by age and type of house, and reduced the variation by education. The direction of the magnitude of the survival estimates was reversed within the different categories of occupation, marital status and household income in the screen-detected cancer cases compared to control group cancer cases. Also, women diagnosed with stage 1 disease had a very good survival. Conclusions: Screening changed the pattern of survival by socio-economic factors. We found improved survival rates in screened women aged <50 years, with no formal education, manual workers and married women.
    No preview · Article · Aug 2015 · Asian Pacific journal of cancer prevention: APJCP
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    ABSTRACT: Background: Screening for colorectal cancer (CRC) with guaiac-based faecal occult-blood test (FOBT) has been reported to reduce CRC mortality in randomised trials in the 1990s, but not in routine screening, so far. In Finland, a large randomised study on biennial FOB screening for CRC was gradually nested as part of the routine health services from 2004. We evaluate the effectiveness of screening as a public health policy in the largest population so far reported. Methods: We randomly allocated (1:1) men and women aged 60-69 years to those invited for screening and those not invited (controls), between 2004 and 2012. This resulted in 180 210 subjects in the screening arm and 180 282 in the control arm. In 2012, the programme covered 43% of the target age population in Finland. Results: The median follow-up time was 4.5 years (maximum 8.3 years), with a total of 1.6 million person-years. The CRC incidence rate ratio between the screening and control arm was 1.11 (95% CI 1.01 to 1.23). The mortality rate ratio from CRC between the screening and control arm was 1.04 (0.84 to 1.28), respectively. The CRC mortality risk ratio was 0.88 (0.66 to 1.16) and 1.33 (0.94 to 1.87) in males and females, respectively. Conclusions: We did not find any effect in a randomised health services study of FOBT screening on CRC mortality. The substantial effect difference between males and females is inconsistent with the evidence from randomised clinical trials and with the recommendations of several international organisations. Even if our findings are still inconclusive, they highlight the importance of randomised evaluation when new health policies are implemented. Trial registration: 002_2010_august.
    Full-text · Article · Jun 2015
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    ABSTRACT: Prostate cancer (PC) screening with prostate-specific antigen (PSA) has been shown to decrease PC mortality in the European Randomized Study of Screening for Prostate Cancer (ERSPC). However, in the Finnish trial, which is the largest component of the ERSPC, no statistically significant mortality reduction was observed. We investigated which had the largest impact on PC deaths in the screening arm: nonparticipation, interval cancers or PSA threshold.The screening (SA) and control (CA) arms comprised altogether 80,144 men. Men in the SA were screened at four-year intervals and referred to biopsy if the PSA concentration was ≥4.0 ng/ml, or 3.0-3.99 ng/ml with a free/total PSA ratio ≤16%. The median follow-up was 15.0 years. A counterfactual exclusion method was applied to estimate the effect of three subgroups in the SA: the nonparticipants, the screen-negative men with PSA ≥3.0ng/ml and a subsequent PC diagnosis, and the men with interval PCs.The absolute risk of PC death was 0.76% in the SA and 0.85% in the CA; the observed hazard ratio (HR) was 0.89 (95% confidence interval (CI) 0.76-1.04). After correcting for nonattendance, the HR was 0.78 (0.64-0.96); predicted effect for a hypothetical PSA threshold of 3.0 ng/ml the HR was 0.88 (0.74-1.04) and after eliminating the effect of interval cancers the HR was 0.88 (0.74-1.04).Nonparticipating men in the SA had a high risk of PC death and a large impact on PC mortality. A hypothetical lower PSA threshold and elimination of interval cancers would have had a less pronounced effect on the screening impact. © 2014 Wiley Periodicals, Inc.
    Full-text · Article · May 2015 · International Journal of Cancer
  • Matti Hakama · Arun Pokhrel · Nea Malila · Timo Hakulinen
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    ABSTRACT: Studies on cancer screening often evaluate the performance by indirect indicators. In case the screening detects pre-invasive lesions, they may be a mixture of benefit of sensitivity and effect as well as of harm of over-diagnosis. Here, we develop the formulae for the sensitivity, the effect, and over-diagnosis in screening for pre-invasive lesions of cancer. Sensitivity is the ability of screening to identify a progressive lesion at the level of test (relevant for the laboratory), episode (relevant in the clinic) and program (relevant at the population level). Effect is reduction of cancer incidence in those screened (efficacy) and in the target population (effectiveness).The sensitivity is estimated by interval cancers between two consecutive screens (incidence method) and the effect by interval cancers and cancers detected at the subsequent screen. Over-diagnosis is estimated as the detection rate of pre-invasive lesions minus the rate of invasive cancer prevented by screening in one screening round. All the indicators are corrected for nonattendance and selective attendance by disease risk. The population to be followed and the period of follow-up are defined for each indicator separately. Data on cervix cancer screening with Papnet® automation device are given as an example.Estimation of sensitivity and effect are consistent with the purpose of the screening to prevent invasive disease. We further define the purpose at the level of laboratory, clinical medicine and public health and derive six estimators corresponding to the specific purposes considered in this paper. © 2014 Wiley Periodicals, Inc.
    No preview · Article · Feb 2015 · International Journal of Cancer
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    ABSTRACT: To estimate the long-term risk of cervical cancer among women screened by visual inspection with acetic acid (VIA) and to evaluate the benefit of additional colposcopy triage in rural south India. A retrospective analysis was conducted among 31 343 women who had undergone VIA at Dindigul district, India between January 1, 2000, and August 5, 2003, as part of a randomized screening trial. Women with positive VIA test results were offered colposcopy triage by trained nurses. Cervical cancer incidence data during follow-up (January 1, 2000, to December 31, 2012) were obtained from a regional cancer registry. Among 3021 screen-positive women free of cancer at baseline, 2974 women underwent colposcopy; colposcopic abnormalities suggestive of precancerous lesions were detected among 2792 of these women (93.9%). Compared with the women with negative VIA screening results, the hazard ratio (HR) of cervical cancer during follow-up among the VIA-positive women without colposcopic abnormalities was 6.5 (95% confidence interval [CI], 1.6-27.1). The risk was similar among VIA-positive women with colposcopic abnormalities but without histological confirmation (HR5.2; 95% CI, 1.9-14.6). The high risk of cancer among women without colposcopic abnormalities who tested positive by VIA suggested that screening without triage is potentially effective. Copyright © 2015 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
    No preview · Article · Jan 2015 · International Journal of Gynecology & Obstetrics
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    Full-text · Article · Jan 2015
  • A. Auvinen · M. Hakama
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    ABSTRACT: The objective of screening is to reduce the public health burden from the target disease. For cancer, this means primarily prevention of cancer deaths. For some cancer types, a premalignant lesion can be detected by screening and treated, so that incidence of invasive cancer can be lowered. Before adopting a cancer screening program as public health policy, a favorable balance of benefits and harms must be demonstrated and the effectiveness of any cancer screening program monitored and evaluated. Currently sufficient evidence exists for cytologic smears for cervical cancer, mammography screening for breast cancer, as well as fecal occult blood testing and sigmoidoscopy screening for colorectal cancer. Evidence is conflicting or insufficient for prostate and lung cancer screening.
    No preview · Article · Dec 2014
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    ABSTRACT: Background: Ductal carcinoma in situ (DCIS) incidence has grown with the implementation of screening and its detection varies across International Cancer Screening Network (ICSN) countries. The aim of this survey is to describe the management of screen-detected DCIS in ICSN countries and to evaluate the potential for treatment related morbidity. Methods: We sought screen-detected DCIS data from the ICSN countries identified during 2004-2008. We adopted standardised data collection forms and analysis and explored DCIS diagnosis and treatment processes ranging from pre-operative diagnosis to type of surgery and radiotherapy. Results: Twelve countries contributed data from a total of 15 screening programmes, all from Europe except the United States of America and Japan. Among women aged 50-69 years, 7,176,050 screening tests and 5324 screen-detected DCIS were reported. From 21% to 93% of DCIS had a pre-operative diagnosis (PO); 67-90% of DCIS received breast conservation surgery (BCS), and in 41-100% of the cases this was followed by radiotherapy; 6.4-59% received sentinel lymph node biopsy (SLNB) only and 0.8-49% axillary dissection (ALND) with 0.6% (range by programmes 0-8.1%) being node positive. Among BCS patients 35% received SLNB only and 4.8% received ALND. Starting in 2006, PO and SLNB use increased while ALND remained stable. SLNB and ALND were associated with larger size and higher grade DCIS lesions. Conclusions: Variation in DCIS management among screened women is wide and includes lymph node surgery beyond what is currently recommended. This indicates the presence of varying levels of overtreatment and the potential for its reduction.
    Full-text · Article · Aug 2014 · European Journal of Cancer
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    ABSTRACT: Background The European Randomised study of Screening for Prostate Cancer (ERSPC) has shown significant reductions in prostate cancer mortality after 9 years and 11 years of follow-up, but screening is controversial because of adverse events such as overdiagnosis. We provide updated results of mortality from prostate cancer with follow-up to 2010, with analyses truncated at 9, 11, and 13 years. Methods ERSPC is a multicentre, randomised trial with a predefined centralised database, analysis plan, and core age group (55–69 years), which assesses prostate-specific antigen (PSA) testing in eight European countries. Eligible men aged 50–74 years were identified from population registries and randomly assigned by computer generated random numbers to screening or no intervention (control). Investigators were masked to group allocation. The primary outcome was prostate cancer mortality in the core age group. Analysis was by intention to treat. We did a secondary analysis that corrected for selection bias due to non-participation. Only incidence and no mortality data at 9 years’ follow-up are reported for the French centres. This study is registered with Current Controlled Trials, number ISRCTN49127736. Findings With data truncated at 13 years of follow-up, 7408 prostate cancer cases were diagnosed in the intervention group and 6107 cases in the control group. The rate ratio of prostate cancer incidence between the intervention and control groups was 1·91 (95% CI 1·83–1·99) after 9 years (1·64 [1·58–1·69] including France), 1·66 (1·60–1·73) after 11 years, and 1·57 (1·51–1·62) after 13 years. The rate ratio of prostate cancer mortality was 0·85 (0·70–1·03) after 9 years, 0·78 (0·66–0·91) after 11 years, and 0·79 (0·69–0·91) at 13 years. The absolute risk reduction of death from prostate cancer at 13 years was 0·11 per 1000 person-years or 1·28 per 1000 men randomised, which is equivalent to one prostate cancer death averted per 781 (95% CI 490–1929) men invited for screening or one per 27 (17–66) additional prostate cancer detected. After adjustment for non-participation, the rate ratio of prostate cancer mortality in men screened was 0·73 (95% CI 0·61–0·88). Interpretation In this update the ERSPC confirms a substantial reduction in prostate cancer mortality attributable to testing of PSA, with a substantially increased absolute effect at 13 years compared with findings after 9 and 11 years. Despite our findings, further quantification of harms and their reduction are still considered a prerequisite for the introduction of populated-based screening. Funding Each centre had its own funding responsibility.
    Full-text · Article · Aug 2014 · The Lancet
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    Sanni Helander · Matti Hakama · Nea Malila
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    ABSTRACT: To explore effects of a pre-screening life style survey on the subsequent attendance proportion in colorectal cancer screening. Finnish colorectal cancer screening programme in 2011. Double randomized and controlled follow-up design. The study population comprised of 31,951 individuals born in 1951. In 2010 to a random sample of every sixth (n = 5,312) person we sent a 7-paged life style questionnaire, and to another random sample of every sixth person (n = 5,336) a 10-paged life style and quality of life questionnaire. One year later, in 2011, 31,484 individuals of the original cohort were independently randomized (1:1) for colorectal cancer screening (n = 15,748) or control group (n = 15,736). Of those who were invited for screening, 5185 had received a questionnaire during the previous year. 5870 individuals (55.1 %) responded to the questionnaire in 2010. The overall attendance at screening in 2011 was 59.0 % in those born in 1951 (i.e. the 60-year-olds). In those who had been sent the survey the attendance in screening was 56.6% (57.3% for the short and 56.0% for the long questionnaire) and in those who had not received the questionnaire it was 60.2% (P < 0.001). We believe that the observed reduction in attendance in those who had been sent a questionnaire earlier is generally true. Thus, if any survey is enclosed in the screening invitation, this finding should be taken into account when planning the programme. Any extra effort requested may reduce the attendance proportion for screening, reducing the population level impact of screening.
    Full-text · Article · May 2014 · Journal of Medical Screening
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    ABSTRACT: Background There is concern about detection of ductal carcinoma in situ (DCIS) in screening mammography. DCIS accounts for a substantial proportion of screen-detected lesions but its effect on breast cancer mortality is debated. The International Cancer Screening Network conducted a comparative analysis to determine variation in DCIS detection. Patients and Methods Data were collected during 2004–2008 on number of screening examinations, detected breast cancers, DCIS cases and Globocan 2008 breast cancer incidence rates derived from national or regional cancer registers. We calculated screen-detection rates for breast cancers and DCIS. Results Data were obtained from 15 screening settings in 12 countries; 7,176,050 screening examinations; 29,605 breast cancers and 5324 DCIS cases. The ratio between highest and lowest breast cancer incidence was 2.88 (95% confidence interval (CI) 2.76–3.00); 2.97 (95% CI 2.51–3.51) for detection of breast cancer; and 3.49 (95% CI 2.70–4.51) for detection of DCIS. Conclusions Considerable international variation was found in DCIS detection. This variation could not be fully explained by variation in incidence nor in breast cancer detection rates. It suggests the potential for wide discrepancies in management of DCIS resulting in overtreatment of indolent DCIS or undertreatment of potentially curable disease. Comprehensive cancer registration is needed to monitor DCIS detection. Efforts to understand discrepancies and standardise management may improve care.
    Full-text · Dataset · Apr 2014
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    ABSTRACT: Background There is concern about detection of ductal carcinoma in situ (DCIS) in screening mammography. DCIS accounts for a substantial proportion of screen-detected lesions but its effect on breast cancer mortality is debated. The International Cancer Screening Network conducted a comparative analysis to determine variation in DCIS detection. Patients and Methods Data were collected during 2004–2008 on number of screening examinations, detected breast cancers, DCIS cases and Globocan 2008 breast cancer incidence rates derived from national or regional cancer registers. We calculated screen-detection rates for breast cancers and DCIS. Results Data were obtained from 15 screening settings in 12 countries; 7,176,050 screening examinations; 29,605 breast cancers and 5324 DCIS cases. The ratio between highest and lowest breast cancer incidence was 2.88 (95% confidence interval (CI) 2.76–3.00); 2.97 (95% CI 2.51–3.51) for detection of breast cancer; and 3.49 (95% CI 2.70–4.51) for detection of DCIS. Conclusions Considerable international variation was found in DCIS detection. This variation could not be fully explained by variation in incidence nor in breast cancer detection rates. It suggests the potential for wide discrepancies in management of DCIS resulting in overtreatment of indolent DCIS or undertreatment of potentially curable disease. Comprehensive cancer registration is needed to monitor DCIS detection. Efforts to understand discrepancies and standardise management may improve care.
    Full-text · Article · Jan 2014 · European Journal of Cancer
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    ABSTRACT: To compare outcome of lower urinary tract symptoms (LUTS) between men with medical and surgical treatment. A questionnaire was mailed to men aged 55, 65 and 75 years living in Tampere region, Finland in 1999 and the survey was repeated in 2004. LUTS were evaluated using DAN-PSS-1 questionnaire. A total of 1679 men (68% of the eligible) responded to both questionnaires. Of them, 114 men reported LUTS at baseline and medical treatment in the repeat survey and 47 men with LUTS had received surgical treatment. Seventy-two men with prostate cancer were excluded. Men with no medical treatment or surgery for LUTS in either questionnaire were included to no-treatment group. The men after surgical treatment showed a reduction in all LUTS symptom groups. However, among the medically treated and untreated men, all the symptoms worsened during the follow up. The proportion of symptomatic men after surgery was lower than among the medically treated men. In men with medical treatment, the prevalence of all 12 LUTS increased. Dysuria and postmicturition dribble were the only symptoms that had slightly better results in medical than in surgical treatment group. In this population-based study, operative treatment seemed to relieve LUTS, whereas medical treatment only slowed down their progression. These findings suggest that men with surgical treatment experience a more favourable outcome in LUTS than those receiving medical treatment.
    No preview · Article · Dec 2013 · International Journal of Clinical Practice
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    Article: My 50 years
    Matti Hakama

    Preview · Article · Jun 2013 · Acta oncologica (Stockholm, Sweden)
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    ABSTRACT: We compared test sensitivity (in terms of prevented cancers) and overdiagnosis (in terms of non-progressive pre-invasive lesions) between the human papillomavirus test (HPV test, Hybrid Capture 2) and the traditional Pap test in routine screening for cervical cancer. The design was a randomised (1:1) health services study in Finland with intake between 2003 and 2007. We estimated sensitivity by the incidence method within one screening round. Overdiagnosis was based on the rate of cervical intraepithelial Grade 3 (CIN3) lesions diagnosed at screen and during the following interval. Out of 203,788 randomised women 132,298 attended (65% in both study arms) and 600,753 person-years accumulated among attenders up to the end of 2010. In all attenders, 34 invasive cervical cancers and 288 CIN3 lesions were diagnosed at screen or during the following interval. The interval cancer incidence was 2.5/10(5) person-years (sensitivity 0.87) and 1.4 (sensitivity 0.93) in the HPV arm and Pap test arm, respectively. The rate of CIN3 lesions was 57.1 and 38.8, respectively. In conclusion, sensitivity of HPV testing was similar to that of Pap testing but caused more overdiagnosis. Therefore, implementation of HPV testing needs to be reconsidered especially in countries with well organised programmes.
    Full-text · Article · May 2013 · International Journal of Cancer
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    ABSTRACT: Background Prostate cancer (PC) screening with prostate-specific antigen (PSA) has been shown to decrease PC mortality by the European Randomized Study of Screening for Prostate Cancer (ERSPC). We evaluated mortality results in the Finnish Prostate Cancer Screening Trial, the largest component of ERSPC. The primary endpoint was PC-specific mortality.MethodsA total of 80 144 men were identified from the population registry and randomized to either a screening arm (SA) or a control arm (CA). Men in the SA were invited to serum PSA determination up to three times with a 4-year interval between each scan and referred to biopsy if the PSA concentration was greater than or equal to 4.0ng/mL or 3.0 to 3.99ng/mL with a free/total PSA ratio less than or equal to 16%. Men in the CA received usual care. The analysis covers follow-up to 12 years from randomization for all men. Hazard ratios (HRs) were estimated for incidence and mortality using Cox proportional hazard model. All statistical tests were two-sided.ResultsPC incidence was 8.8 per 1000 person-years in the SA and 6.6 in the CA (HR = 1.34, 95% confidence interval [CI] = 1.27 to 1.40). The incidence of advanced PC was lower in the SA vs CA arm (1.2 vs 1.6, respectively; HR = 0.73, 95% CI = 0.64 to 0.82; P < .001). No statistically significant difference was observed between the SA and CA (HR = 0.85, 95% CI = 0.69 to 1.04) (with intention-to-screen analysis). To avoid one PC death, we needed to invite 1199 men to screening and to detect 25 PCs. We observed no difference in all-cause mortality between trial arms.Conclusions At 12 years, a relatively conservative screening protocol produced a small, non-statistically significant PC-specific mortality reduction in the Finnish trial, at the cost of moderate overdiagnosis.
    Full-text · Article · Mar 2013 · Journal of the National Cancer Institute
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    ABSTRACT: Background: Prospective cohort studies to determine cofactors with oncogenic HPV- infections for cervical cancer are very rare from developing countries and such data are limited to the few screening trials. Large screening trials provide such data as a by product. Some of the cases are prevented by screening and do not surface as invasive cancers at all. Also, pre-invasive lesions are detected almost entirely by screening. Screening causes selection bias if attendance in or effectiveness of screening is correlated with the risk factors. The aim of this study was to quantify the influence of screening on risk factors for cervical cancer. Materials and methods: Our material stems from a rural cohort of 80,000 women subjected to a randomised screening trial. The effect of screening on the incidence of cervix cancer was estimated with reference to socio-demographic and reproductive risk factors of cervical cancer. We compared these risks with the incidence of cancer in the randomised control population by the same determinants of risk. Results: The results in the screening arm compared to the control arm showed that the women of low SES and young age were benefitting more than those of high SES and old age. The relative risk by age (30-39 vs 50-59) was 0.33 in the control arm and 0.24 in the screening arm. The relative risk by education (not educated vs educated) was 2.8 in the control arm and 1.8 in the screening arm. The previously married women did not benefit (incidence 113 and 115 per 100,000 women years in control vs screening arms) whereas the effect was substantial in those married (86 vs 54). Conclusions: The results in controls were consistent with the general evidence, but results in attenders and nonattenders of the screening arm showed that screening itself and self-selection in attendance and effectiveness can influence the effect estimates of risk factors. The effect of cervical cancer screening programmes on the estimates of incidence of cervical cancer causes bias in the studies on etiology and, therefore, they should be interpreted with caution.
    No preview · Article · Jan 2013 · Asian Pacific journal of cancer prevention: APJCP

Publication Stats

14k Citations
2,061.79 Total Impact Points

Institutions

  • 1978-2015
    • University of Tampere
      • • School of Health Sciences
      • • Department of Public Health
      • • Department of Biomedical Sciences
      Tammerfors, Pirkanmaa, Finland
  • 1974-2015
    • Finnish Cancer Registry, Helsinki
      Helsinki, Southern Finland Province, Finland
  • 2011
    • Tata Memorial Centre
      • Pathology
      Mumbai, Maharashtra, India
  • 2006
    • University of Tartu
      • Department of Public Health (ARTH)
      Dorpat, Tartu, Estonia
  • 2003-2005
    • International Agency for Research on Cancer
      • Section of Cancer Information
      Lyons, Rhône-Alpes, France
  • 2000-2005
    • Tampere University Hospital (TAUH)
      Tammerfors, Pirkanmaa, Finland
  • 2002
    • Säteilyturvakeskukseen
      Helsinki, Uusimaa, Finland
    • National Public Health Institute
      Helsinki, Uusimaa, Finland
  • 1974-2001
    • Kuopio University Hospital
      • Department of Urology
      Kuopio, Northern Savo, Finland
  • 1977-1999
    • University of Helsinki
      • • Department of Dental Public Health
      • • Department of Pathology
      Helsinki, Southern Finland Province, Finland
  • 1997
    • Umeå University
      • Department of Public Health and Clinical Medicine
      Umeå, Västerbotten, Sweden
  • 1995
    • Helsinki University Central Hospital
      • Department of Obstetrics and Gynaecology
      Helsinki, Southern Finland Province, Finland
  • 1988-1993
    • Kela - The Social Insurance Institution of Finland
      • Research Department
      Helsinki, Uusimaa, Finland
  • 1990
    • University of Toronto
      Toronto, Ontario, Canada