Mortality audit of the Finnish cervical cancer screening program

Abstract

Incidence-based evaluations of cervical cancer screening programs have suggested age-specific impacts and there is uncertainty regarding the effectiveness of screening outside the ages of 30-60 years. We audited the screening histories of cervical cancer deaths and conducted a case-control evaluation of the effectiveness of organized screening in different ages with mortality as outcome. We included all 506 cervical cancer deaths in Finland in 2000-2009 due to cancers diagnosed in 1990 or later, and 3,036 controls matched by age at diagnosis to the cases. Squamous cell carcinoma constituted 59% of the cases, adenocarcinomas 29%, and the remaining 12% were other specified and unspecified cervical malignancies. Most deaths (54%) were due to cancers diagnosed more than 5 years after last screening invitation, 24% were diagnosed among nonattenders and only 14% of deaths occurred among women who had attended invitational screening. The risk reduction associated with attending a single program screen at an age below 40 was nonsignificant (OR 0.70; 95% CI 0.33-1.48), while clear risk reductions were observed after screening at the age of 40-54 (OR 0.33; CI 0.20-0.56) and 55-69 (OR 0.29; CI 0.16-0.54). This study also provides some indication of a long-lasting additional effect of screening at the age of 65. Possible avenues for improving the effectiveness of the Finnish screening program include efforts to increase attendance and an extension of the target ages to include 65-to 69-year-old women. The potential benefit of increasing the sensitivity of the screening test or shortening the screening interval is smaller.The effectiveness of cervical cancer screening by cytology has never been established in a randomized controlled trial, but numerous observational studies have confirmed the considerable potential for prevention of cancer incidence and mortality. 1 However, recent research suggests that screening may not be equally effective in all age-groups currently targeted by screening programmes. 2,3 In a case-control evaluation of the Finnish program, no effect on the risk of cancer in the following 5-year interval was found after participation at the age of 25-29. 2 Risk reductions increased with increasing age up to 40, and remained fairly constant thereafter. Similarly, a case-control study from the UK found screening to be less effective in women aged 20-34 and that the efficacy decreases with decreasing age even within this age range. 3 By contrast, a Swedish audit found screening to be equally effective in preventing cancer diagnosed in the ages 21-29 and 30-65. 4 To our knowledge no mortality based effectiveness studies have yet addressed this issue.The purpose of this study was to audit the screening histories of women who died of cervical cancer and evaluate the impact of participation in organized screening on the mortality from cervical cancer by morphology in different ages. We especially wanted to explore how screening at the age of 65 affects the mortality at advanced ages. Material and MethodsThe cerv...

Impact of cervical screening on cervical cancer mortality: estimation using stage-specific results from a nested case–control study

“…Vicus et al (2014) analysed 1052 deaths from cervical cancer in Canada, and found that attending screening in the 3–36 months before cervical cancer diagnosis reduced mortality by 40–72%, depending on age, but that screening 37–60 or 61–120 months before diagnosis was not associated with any reduction in risk. Lonnberg et al (2013) analysed data on 506 women who had died from cervical cancer in 2000–2009. Overall, they reported a 66% reduction in mortality associated with attending a single programme screen.…”

The implementation of an organised cervical screening programme in Poland: an analysis of the adherence to European guidelines

“…Some of the cytological labs working outside the programme in the opportunistic screening are not monitored and their quality is unknown. Data on mortality audits and interval cancers have been published for some countries [45], but no such attempts have been made for Poland yet. Quality of colposcopy, and histopathology should be assured as well [46].…”

Improving cervical cancer screening attendance in Finland

“…1 Adjusted for age, mother tongue, municipality type, education level, marital status and geographical location. 2 Including also 163 women aged 25-29 years in the routine screening group and 38 in the self-sampling group. 3 Including also 279 women aged 65-67 years in the routine screening group and 33 in the self-sampling group.…”

“…2 Option valid only in 2012 invitations. 3 Women received a letter informing them about the upcoming self-sampling test and giving an opportunity to decline beforehand.…”

“…In Finland, a substantial proportion of cancer incidence and especially mortality among women in screening ages 30-60 years is seen among nonattendees. 1,2 Attendance in the program is currently 70% with a slightly decreasing trend (www.cancerregistry.fi).…”