Letter to the Editor

How to improve cervical cancer screening in Switzerland?

DOI: https://doi.org/10.4414/smw.2012.13663
Publication Date: 13.08.2012
Swiss Med Wkly. 2012;142:w13663

Patrick Petignata, Sarah Untieta, Pierre Vassilakosb

a Department of Gynecology, University Hospitals of Geneva, Switzerland
b Geneva Foundation for Medical Education and Research, Geneva, Switzerland

 

Cervical cancer is the cancer that can be the most effectively prevented by screening. Western countries have implemented Pap smear screening and there is highly effective treatment for women with high-grade lesions or early stage invasive cancer, such as laser vaporisation or excision, cryotherapy or hysterectomy. This strategy has led to a decrease of incidence, morbidity and mortality from this disease.

In Switzerland, cervical cancer screening has been promoted by gynaecologists since the late 1960’s and it is estimated that it has reduced its incidence by approximately 50 to 60% [1]. The country has an opportunistic screening system essentially based on the gynaecologist’s invitation for an “annual control”. Cervical cancer screening recommendations were edited by the Swiss Society of Gynaecology and Obstetrics (SSGO) in 2004 and suggest yearly Pap smears, starting one year after first sexual intercourse [2].

This opportunistic system is difficult to monitor and the only available data are from population-based surveys conducted by the Swiss Federal Office of Public Health and the National Institute for Cancer Epidemiology (NICER) [3]. Accordingly a relatively high coverage rate seems to be achieved with approximately 70% of eligible women having had a Pap smear in the last 3 years and a cervical cancer incidence rate which is among the lowest in Western countries (4.0/100,000) [4].

The drawback of the system is that women from lower socioeconomic groups and those living in rural areas have a higher risk of developing cervical cancer [5]. This might be related to a main shortcoming of the system, in that parts of the society are over-screened while others are under-screened. The Federal Office of Public Health estimated that 1 to 1.2 million Pap smears are taken annually to cover approximately 70% of the population, although 520,000 would be enough to cover 100% of the eligible population [6].

Unnecessary screening tests do not only waste precious health care resources but might unintentionally cause significant harm to individuals. Women undergoing unnecessary screening are more likely to get false positive results without reducing their risk to develop cervical cancer [7, 8]. Consequences are unnecessary follow-up testing, increased risk of colposcopic investigation and cervical surgery causing potentially adverse birth outcomes due to increasing the risk of premature deliveries [9, 10].

Recent development of tests for human papillomavirus (HPV) has created an important change in our understanding of cervical cancer screening. Overwhelming evidence from meta-analyses, randomised trials, long prospective cohort studies and routine practice supports that HPV screening is more sensitive than cytological screening for the detection of histological cervical intraepithelial neoplasia (CIN3) or cancer, and that it also enhances the identification of women at risk for adenocarcinoma whose incidence is on the rise in Western countries [11–17]. A sizeable body of evidence supports that a woman’s risk of developing CIN3 or cancer is very low in a 5-year period following a negative HPV test and establishes a high negative predictive value of the HPV test allowing a safe and cost-effective lengthening of cervical cancer screening periods [18, 19]. For women aged 30 years and older, new guidelines should include testing for HPV. For women younger than 30 years, HPV testing should be avoided, because HPV infection is common [11, 20]. In this age group a Pap smear should be performed at three year intervals.

From a public health perspective and in terms of cost effectiveness, cervical cancer prevention could be improved by the replacement of frequent cytology tests by HPV screening every 5 years. Moreover, the use of HPV testing as a primary screening test would be a useful tool for the monitoring of HPV vaccination programmes introduced in Switzerland in 2008.

A shift to a new screening technology must be accompanied by efforts to heighten the participation of unscreened women. Self-collected samples for HPV testing should be an appropriate strategy to reach these women [21, 22].

Switzerland has a low cervical cancer incidence supporting that the current screening system is efficient. However, health care systems are necessarily concerned about costs of cervical cancer prevention. Both over-screening and under-screening have negative health and financial consequences, therefore a more organised approach including HPV testing conducted at adequate interval as well as strategies to improve participation of non-covered women will maximise the benefits and minimise the adverse effects of screening. Undoubtedly, rationalisation of the policy and the evolution to a more organised approach having quality assurance at all appropriate levels will be necessary, but the change might be difficult to introduce in a liberal health care system because each interest group has its own directives and limitations. Therefore a broad consensus on cervical cancer screening should be initiated by the concerned professional scientific society [10]. Health care providers must also ensure that their patients fully understand what is known about the benefits and harm from cervical cancer screening to allow a personal choice.

Funding / potential competing interests: No financial support and no other potential conflict of interest relevant to this article were reported.

Correspondence

Correspondence: Sarah Untiet, MD, University Hospitals of Geneva, Boulevard de la Cluse 30, CH-1211 Geneva 14, Switzerland, sarah.untiet[at]hcuge.ch

References

  1 Bouchardy C, Fioretta G, Raymond L, Vassilakos P. Age differentials in trends of uterine cervical cancer incidence from 1970 to 1987 in Geneva. Revue d’epidemiologie et de sante publique. 1990;38:261–2.

  2 SGGG AGZ. Guideline zum Vorgehen bei suspektem und positivem zytologischen Abstrich der Cervix Uteri (überarbeitete Fassung, Version 2.4.). Schweizerische Gesellschaft für Gynäkologie und Geburtshilfe; 2004. p. 3–27.

  3 Cullati S, Charvet-Berard AI, Perneger TV. Cancer screening in a middle-aged general population: factors associated with practices and attitudes. BMC Public Health. 2009;9:118.

  4 EKIF. Directive and recommendation no. 21: HPV vaccination recommendation 2007.

  5 Bouchardy C, Pury P, Raymond L. Le cancer en suisse: principales données épidémiologiques (2e partie). Bull Suisse Cancer. 2005;2:121–8.

  6 Petignat P, Bouchardy C, Sauthier P. Cervical cancer screening: current status and perspectives. Rev Med Suisse. 2006;2:1308–9, 11–2.

  7 Kulasingam SL, Havrilesky L, Ghebre R, Myers ER. Screening for cervical cancer: a decision analysis for the US preventive services task force. Rockville (MD)2011.

  8 Castle PE, Sideri M, Jeronimo J, Solomon D, Schiffman M. Risk assessment to guide the prevention of cervical cancer. Am J Obstet Gynecol. 2007;197:356 e1–6.

  9 Van Hentenryck M, Noel JC, Simon P. Obstetric and neonatal outcome after surgical treatment of cervical dysplasia. European journal of obstetrics, gynecology, and reproductive biology. 2012;162:16–20.

10 Adab P, McGhee SM, Yanova J, Wong CM, Hedley AJ. Effectiveness and efficiency of opportunistic cervical cancer screening: comparison with organized screening. Medical care. 2004;42:600–9.

11 Bigras G, de Marval F. The probability for a Pap test to be abnormal is directly proportional to HPV viral load: results from a Swiss study comparing HPV testing and liquid-based cytology to detect cervical cancer precursors in 13,842 women. Br J Cancer. 2005;93:575–81.

12 Cuzick J, Clavel C, Petry KU, Meijer CJ, Hoyer H, Ratnam S, et al. Overview of the European and North American studies on HPV testing in primary cervical cancer screening. Int J Cancer. 2006;119:1095–101.

13 Bulk S, Bulkmans NW, Berkhof J, Rozendaal L, Boeke AJ, Verheijen RH, et al. Risk of high-grade cervical intra-epithelial neoplasia based on cytology and high-risk HPV testing at baseline and at 6-months. Int J Cancer. 2007;121:361–7.

14 Bulkmans NW, Berkhof J, Rozendaal L, van Kemenade FJ, Boeke AJ, Bulk S, et al. Human papillomavirus DNA testing for the detection of cervical intraepithelial neoplasia grade 3 and cancer: 5-year follow-up of a randomised controlled implementation trial. Lancet. 2007;370:1764–72.

15 Naucler P, Ryd W, Tornberg S, Strand A, Wadell G, Elfgren K, et al. Human papillomavirus and Papanicolaou tests to screen for cervical cancer. N Engl J Med. 2007;357:1589–97.

16 Mayrand MH, Duarte-Franco E, Rodrigues I, Walter SD, Hanley J, Ferenczy A, et al. Human papillomavirus DNA versus Papanicolaou screening tests for cervical cancer. N Engl J Med. 2007;357:1579–88.

17 Ronco G, Giorgi-Rossi P, Carozzi F, Confortini M, Dalla Palma P, Del Mistro A, et al. Efficacy of human papillomavirus testing for the detection of invasive cervical cancers and cervical intraepithelial neoplasia: a randomised controlled trial. Lancet Oncol. 2010;11:249–57.

18 Dillner J, Rebolj M, Birembaut P, Petry KU, Szarewski A, Munk C, et al. Long term predictive values of cytology and human papillomavirus testing in cervical cancer screening: joint European cohort study. BMJ. 2008;337:a1754.

19 Khan MJ, Castle PE, Lorincz AT, Wacholder S, Sherman M, Scott DR, et al. The elevated 10-year risk of cervical precancer and cancer in women with human papillomavirus (HPV) type 16 or 18 and the possible utility of type-specific HPV testing in clinical practice. J Natl Cancer Inst. 2005;97:1072–9.

20 Almonte M, Sasieni P, Cuzick J. Incorporating human papillomavirus testing into cytological screening in the era of prophylactic vaccines. Best practice & research Clinical obstetrics & gynaecology. 2011;25:617–29.

21 Petignat P, Vassilakos P. Is it time to introduce HPV self-sampling for primary cervical cancer screening? J Natl Cancer Inst. 2012.

22 Petignat P, Faltin DL, Bruchim I, Tramer MR, Franco EL, Coutlee F. Are self-collected samples comparable to physician-collected cervical specimens for human papillomavirus DNA testing? A systematic review and meta-analysis. Gynecol Oncol. 2007;105:530–5.

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