Tsiodras et al. BMC Cancer 2010, 10:53 http://www.biomedcentral.com/1471-2407/10/53 this association and support the strong rationale for pre- ventive HPV vaccination in our population. The rate of invasive carcinoma discovered in this study is indicative of a largely unscreened population. The reasons and possible solutions for this observation are an important public health issue and should be further investigated. Moreover the effect of the intro- duction of newer techniques in population screening is a matter of intense research. Despite the excellent results with cytology in this study, it is well known that screening for cytological changes may have limited sen- sitivity and findings are not always reproducible [8]. In a country where screening is largely opportunistic and based on self-referral results of cytological testing are expected to be much worse than the ones presented here. Moreover, molecular HPV testing should not be introduced without careful planning; results of such testing should be communicated and explained appro- priately in the context of prevalence of the disease. Conclusion In conclusion, the present study was more of a technical nature and focused on strengths and weakness of cur- rent screening methods in correlation with histological findings. HPV rates were high in high grade lesions in accordance to published literature however HPV was also identified in a large fraction of samples with normal cytology or in samples with normal biopsies. The best approach for such samples will be guided after careful identification of the local epidemiology of the transmis- sion and risk factors for HPV acquisition. Newer meth- ods assessing the integration of the virus may be more appropriate in the workup of such cases. In our study in an referral center with experienced doctors, thin prep cytology and molecular HPV tests performed equally well as screening tests in all scenarios and sometimes were complementary to each other. As newer methods to detect HPV continue to evolve it is important to recognize the clinicopathological correlates of such test- ing. This will lead to more appropriate screening strate- gies in the post-vaccine era. Author details 14th Dept of Internal Medicine, Attikon University Hospital, University of Athens Med. Sch. Athens, Greece. 2Department of Cytopathology, Attikon University Hospital, University of Athens Med. Sch. Athens, Greece. 3Department of Histology and Embryology, University of Athens Med. Sch. Athens, Greece. 41st Department of Obstetrics and Gynecology, University of Athens Med. Sch. Athens, Greece. 5Department of Internal Medicine and Oncology, University of Athens Med. Sch. Athens, Greece. 6Department of Cytopathology, Alexandra Hospital, Athens, Greece. 72nd Department of Pathology, Attikon University Hospital, Athens University Medical School, Athens, Greece. Authors’ contributions ST, AC, JG, and PK conceived and participated in the design and coordination of the study; ZV collected thin prep and histology samples; JG, Page 7 of 8 AT and PK performed the thin prep evaluation; AC performed the molecular studies; JP and PK performed the pathological evaluation; ST, JP, AP and PK performed the statistical analysis and analyzed the data; ST, AC, JP and PK drafted the first draft; All authors reviewed and critically revised the first draft; All authors read and approved the final manuscript. Competing interests The authors declare that they have no competing interests. Received: 11 June 2009 Accepted: 22 February 2010 Published: 22 February 2010 References 1. 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