The GP is the largest population-based longitudinal cohort for the study of HPV and cervical neoplasia in the world, and its results will hopefully let us soon plan future worldwide prevention strategies. Research projects such as this one require the long-term commitment of a large multidisciplinary team and ample financial resources. The intensive effort and expertise applied in all aspects of this study were key factors in its success as a model of cooperative, interdisciplinary cancer research in Latin America. Quality control played an important role at all times during the study and made it possible to adapt new diagnostic and screening technology to Guanacaste. The systematic follow-up of a population-based group of close to 10 000 women in Guanacaste should permit careful, time-dependent evaluation of factors postulated to be linked to the development of cervical cancer as well as the evaluation of clinical markers of disease progression. The study results that have already been published have validated sensitive screening techniques and have also promoted the use of more affordable screening techniques in resource-poor, developing countries. The GP has also contributed to building knowledge for the search for vaccines against HPV as part of the effort to develop an effective tool to reduce the incidence and mortality of cervical cancer worldwide.

Cervical screening for carcinogenic human papillomavirus (HPV) infection is being considered for low income countries. Effectiveness requires targeted screening in older women in whom prevalent infections are more likely to be persistent and predictive of precancer. Some studies in West Africa have found unusually high HPV prevalences across all adult ages, that may reduce the positive predictive value (PPV) of HPV-based screening, if positivity in older women does not sufficiently predict elevated risk. We conducted a population-based study in rural Nigeria to identify HPV prevalence and associated cervical abnormalities. Using stratified random sampling, we enrolled women age 15+. Non-virgins had a cervical exam including liquid-based cytology and PCR HPV DNA testing from residual cytology specimens. Two-thirds of invited women participated, and 14.7% had detectable carcinogenic HPV, a proportion that did not decline with age (p-trend=.36) and showed slight peaks in the 15–29 and 60–69 age groups. Among women of the age typically considered for screen-and-treat programs (30–49 years), 12.8% were HPV-positive and the PPV for high-grade or worse cytology was 16.4%. Comparatively, women age <30, were more likely to be HPV-positive (18.9%, p=.03) with a lower PPV (4.2% p=.05). Among women age 50+ (typically excluded from screening in resource-poor settings because inexpensive treatment is not available), HPV positivity was 14.2% with a PPV of 13.9%. In Irun and similar settings where HPV does not decline with age, HPV-based screen-and-treat programs might be feasible for mid-adult women, since prevalence is sufficiently low, positivity predicts elevated risk of more easily treated precancer.

Unlike cutaneous HPV types, alpha mucosal HPV types were uncommon in the oral region and were predominately associated with sexual behavior. Clinical Trials Registration. NCT00128661.

OBJECTIVE Cervical cancer is the most common gynaecological cancer in developing countries. Visual Inspection with Acetic Acid (VIA) was introduced to screen for cervical premalignant lesions in developing countries due to the inability of many countries to implement high quality cytologic services. We sought to compare VIA performance among different health workers in Nigeria. METHODS In a population-based project, seven health workers working who had been screening women with VIA for about two years at local government health centers in rural Nigeria were retrained in a two-week program using the IARC training manual. Women from a rural village who had never had cervical cancer screening were recruited into the study. Each woman had cervical cancer screening by VIA, liquid-based cytology and oncogenic human Papillomavirus (HPV) DNA testing. RESULTS Despite similar participant characteristics, across all age groups, providers had wide ranges of VIA results; 0–21% suspect cancer and 0–25% VIA positive. VIA was insensitive compared to a combination of cytology and HPV testing. CONCLUSION In our study, VIA was not reproducible nor was it sensitive compared to cytology and HPV testing.