title: A population-based prospective study of Chlamydia trachomatis infection and cervical carcinoma.
abstract: Persistent human papillomavirus (HPV) infection is an established cause of cervical cancer, but the role of other sexually transmitted agents, most notably Chlamydia trachomatis, has not been well defined. The women participating in the population-based cervical cancer screening program in Västerbotten county of Northern Sweden were followed up for up to 26 years to identify 118 women who developed cervical cancer after having had a normal Pap smear (on average 5.6 years later; range 0.5 months-26 years). As controls, we selected another 118 women who were matched by birth cohort, time-point of sampling of the baseline normal smear and who had a normal smear at the time when the corresponding case was diagnosed with cancer. The Pap smears and cervical cancer biopsies were analyzed by PCR for C. trachomatis DNA and for HPV DNA. At baseline, C. trachomatis DNA was present in 8% of cases but not among any one of the controls. The relative risk for cervical cancer associated with past C. trachomatis infection, adjusted for concomitant HPV DNA positivity, was 17.1 (95% CI 2.6-infinity). The presence of C. trachomatis and of HPV were not interrelated. Whereas C. trachomatis was primarily found in specimens taken many years before cancer diagnosis, HPV DNA was associated with a short lag time before cancer diagnosis. Whereas most women who were HPV DNA-positive in the prediagnostic smear were also positive for the same virus in the cervical cancer biopsy, none of the women were positive for C. trachomatis in both the prediagnostic smear and in the subsequent cervical cancer. In conclusion, a prior cervical C. trachomatis infection was associated with an increased risk for development of invasive cervical cancer.
authors.affiliation: Department of Molecular Medicine, Karolinska Institute, Stockholm, Sweden. keng-ling.wallin@cmm.ki.se
authors.forename: Keng-Ling
authors.initials: KL
authors.lastname: Wallin
authors.forename: Fredrik
authors.initials: F
authors.lastname: Wiklund
authors.forename: Tapio
authors.initials: T
authors.lastname: Luostarinen
authors.forename: Tord
authors.initials: T
authors.lastname: Angström
authors.forename: Tarja
authors.initials: T
authors.lastname: Anttila
authors.forename: Frank
authors.initials: F
authors.lastname: Bergman
authors.forename: Göran
authors.initials: G
authors.lastname: Hallmans
authors.forename: Irma
authors.initials: I
authors.lastname: Ikäheimo
authors.forename: Pentti
authors.initials: P
authors.lastname: Koskela
authors.forename: Matti
authors.initials: M
authors.lastname: Lehtinen
authors.forename: Ulf
authors.initials: U
authors.lastname: Stendahl
authors.forename: Jorma
authors.initials: J
authors.lastname: Paavonen
authors.forename: Joakim
authors.initials: J
authors.lastname: Dillner
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D002690:Chlamydia Infections / Q000175:diagnosis* / Q000453:epidemiology; D002692:Chlamydia trachomatis / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D006801:Humans; D008875:Middle Aged; D065006:Papanicolaou Test; D027383:Papillomaviridae / Q000235:genetics; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D012306:Risk; D013548:Sweden / Q000453:epidemiology; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis / Q000382:microbiology* / Q000821:virology; D014626:Vaginal Smears
chemical_list: D004269:DNA, Bacterial; D004279:DNA, Viral