RESUMO
BACKGROUND: High-risk human papillomavirus (HR-HPV) are responsible for cervical cancer (CC) which represents the second most prevalent gynecological cancer among Tunisian women. Preventive strategies against CC are based on prophylactic vaccines that have not yet been implemented into the national vaccination program of Tunisia. Therefore, the present study aimed to investigate the HPV genotypes distribution in cervical neoplasia in Tunisian women in order to predict the impact of using current HPV vaccines on cancer prevention in Tunisia. METHODS: A total of 200 formalin-fixed paraffin embedded biopsies were collected in our study. DNA was extracted using Qiagen Mini prep kit. DNA quality was controlled by Beta Globin PCR. Only positive samples for Beta Globin test were used. HPV detection was performed by a nested PCR using PYGMY and GP5+/6+ primers. Genotyping was performed by Reverse Line hybridization using 31 probes. RESULTS: The mean age of participants was 38.97 years and 75% were over 30 years. Cervical neoplasia distribution according to age showed that CINII/CINIII was observed among women over 30 years old. All samples were positive for Beta Globin PCR. Overall HPV prevalence in cervical lesions was 83% (166/200). HPV was present in 65% of CINI, 82% of CINII/CINIII and 85% of CC. HR-HPV was statistically significantly associated with cervical intraepithelial neoplasia (p < 10-3). HR-HPV distribution according to lesion grade and cervical cancer showed that HPV16 and HPV18 were present in all lesions. For CINII/CINIII, HPV 35 (37.5%) was the most detected type, followed by HPV18 (33.3%) HPV 45 (28.5%) and HPV 16 (18.9%). HPV 45(57.5%), HPV 18 (53.3%) were the most detected in CC. HPV58, 59, 68 were only detected in CC and associated with HPV45, 18 and HPV16. HPV39, 31, 33, 52, 56 and HPV70 was associated only with CINI. CONCLUSIONS: Our findings can give useful information for vaccine implementation by helping the health policymakers to choose the most appropriate vaccine type in Tunisia.
RESUMO
Implementation of Human Papillomavirus (HPV) vaccination should be considered a key cervical cancer prevention strategy in Tunisia, where Pap smear screening is not efficient. This study aims to estimate the prevalence and to identify risk factors associated with HPV infection among women from Grand Tunis, Tunisia. We conducted a cross-sectional study, between December 2012 and May 2013. Eligible women for this study were those aged 18-65 years, sexually active, who sought medical attention at their primary health care centre or clinic in Grand Tunis, Tunisia and who gave written consent. A liquid-based Pap smear sample was obtained from all women using a cervical brush. Only women with betaglobin positive test were further analysed for HPV detection and typing. A nested-PCR of the L1 region was performed followed by reverse line blot hybridization to facilitate the specific detection of 31 HPV genotypes. Multiple logistic regression modeling was used for the analysis of associations between variables with some considered possible confounders after checking for interactions. A total of 391 women were enrolled in this study and 325 out of the 391 cervical samples were positive for the betaglobin test. Overall HPV prevalence was 13.2% [9.8%-17.5%], with the following most prevalent HPV genotypes: HPV6 (40%), HPV40 (14%), HPV16 (12%), HPV52 (9%), HPV31 and HPV59 (7%), followed by HPV68 (4%). Mean age of HPV positive women was 40.7±0.92 years. Independently associated risk factors of HPV infection were smoking (OR:2.8 [0.8-9.6]), low income (OR:9.6 [1.4-63.4), bad housing type (OR:2.5 [1-6.8]), partner with multiple sexual relationship (OR:4.5 [0.9-22.9]) and single women (widowed, divorced, separated, never married) (OR:6.9 [1.1-42.2]). This study provides the first national-based estimate of HPV prevalence in Tunisia. Our findings contribute to the evidence on the current burden of HPV infection, the critical role of sexual behaviour and socioeconomic status and call for increased support for the screening program in Tunisia to prevent cervical cancer. These results allow us to evaluate the cost-effectiveness of vaccine program implementation in Tunisia in future.
