Screening for cervical cancer: a systematic review and meta-analysis

Abstract

BackgroundThe systematic review on which this paper is based provided evidence for the Canadian Task Force on Preventive Health Care to update their guideline regarding screening for cervical cancer. In this article we highlight three questions covered in the full review that pertain to the effectiveness of screening for reducing cervical cancer mortality and incidence as well as optimal timing and frequency of screening.MethodsWe searched MEDLINE, Embase and Cochrane Central from 1995 to 2012 for relevant randomized controlled trials and observational studies with comparison groups. Eligible studies included women aged 15 to 70 years who were screened using conventional cytology, liquid-based cytology or human papillomavirus DNA tests. Relevance screening, data extraction, risk of bias analyses and quality assessments were performed in duplicate. We conducted a meta-analysis using a random-effects model on the one body of evidence that could be pooled.ResultsFrom the 15,145 screened citations, 27 papers (24 studies) were included; five older studies located in a United States Preventive Services Task Force review were also included. A randomized controlled trial in India showed even a single lifetime screening test significantly decreased the risk of mortality from and incidence of advanced cervical cancer compared to no screening (mortality: risk ratio 0.65, 95% confidence interval 0.47, 0.90; incidence: relative risk 0.56, 95% confidence interval 0.42, 0.75). Cytology screening was shown to be beneficial in a cohort study that found testing significantly reduced the risk of being diagnosed with invasive cervical cancer compared to no screening (risk ratio 0.38; 95% confidence interval 0.23, 0.63). Pooled evidence from a dozen case–control studies also indicated a significant protective effect of cytology screening (odds ratio 0.35; 95% confidence interval 0.30, 0.41). This review found no conclusive evidence for establishing optimal ages to start and stop cervical screening, or to determine how often to screen; however the available data suggests substantial protective effects for screening women 30 years and older and for intervals of up to five years.ConclusionsThe available evidence supports the conclusion that cervical screening does offer protective benefits and is associated with a reduction in the incidence of invasive cervical cancer and cervical cancer mortality.

Advancing the evaluation of cervical cancer screening: development and application of a longitudinal adherence metric

“…Routine cytology-based screening has contributed to reducing cervical cancer (CC) incidence and mortality worldwide (1,2). Adherence to screening guidelines is considered one of the most important factors for screening effectiveness and efficiency (3)(4)(5)(6), and the European guidelines for quality assurance of CC screening have recognized screening coverage as a key performance indicator (4).…”

Factors Affecting Cervical Cancer Screening Uptake by Hmong Hilltribe Women in Thailand

“…Strong evidence is now available to show that cervical screening is associated with reductions in the incidence of invasive cervical cancer and in mortality and that these benefits can occur even after a single life-time screening test (Peirson et al, 2013). However, for screening to be an effective means of preventing deaths from cervical cancer, it must be widely available, preferably in the form of a well-publicised national programme, women at risk for the disease must participate and attend screening, and those with abnormal smears must be treated.…”

Attitudes and Practice of Cervical Cancer Screening among Female University Students from 25 Low, Middle Income and Emerging Economy Countries

“…It is the seventh most common cancer in the world, and is more common in less developed countries-where it accounts for more than 85% of the global burden of cancer (Globocan, 2012). Cervical screening offers protective benefits and is associated with a reduction in the incidence of invasive cervical cancer and cervical cancer mortality (Peirson et al, 2013). The United States Preventive Services Task Force (USPSTF, 2012) and the American Cancer Society (ACS) recommend that all women should begin cervical cancer screening at age 21, every three years for women ages 21-65.…”