Cervical cancer risk and impact of Pap-based screening in HIV-positive women on antiretroviral therapy in Johannesburg, South Africa.

Data on invasive cervical cancer (ICC) incidence in HIV-positive women and the effect of cervical cancer screening in sub-Saharan Africa are scarce. We estimated i) ICC incidence rates in women (>/=18 years) who initiated antiretroviral therapy (ART) at the Themba Lethu Clinic (TLC) in Johannesburg South Africa between 2004-2011; and ii) the effect of a Pap-based screening program. We included 10640 women; median age at ART initiation: 35 years (interquartile range [IQR] 30-42) median CD4 count at ART initiation: 113 cells/microl (IQR 46-184). During 27257 person-years (pys) 138 women were diagnosed with ICC; overall incidence rate: 506/100000 pys (95% CI 428-598). The ICC incidence rate was highest (615/100000 pys) in women who initiated ART before cervical cancer screening became available in 04/2005 and was lowest (260/100000 pys) in women who initiated ART from 01/2009 onwards when the cervical cancer screening program and access to treatment of cervical lesions was expanded (adjusted hazard ratio [aHR] 0.42 95% confidence interval [CI] 0.20-0.87). Advanced HIV/AIDS stage (4 versus 1 aHR 1.95 95% CI 1.17-3.24) and middle age at ART initiation (36-45 versus 18-25 years aHR 2.51 95% CI 1.07-5.88) were risk factors for ICC. The ICC incidence rate substantially decreased with the implementation of a Pap-based screening program and improved access to treatment of cervical lesions. However the risk of developing ICC after ART initiation remained high. To inform and improve ICC prevention and care for HIV-positive women in sub-Saharan Africa implementation and monitoring of cervical cancer screening programs are essential. This article is protected by copyright. All rights reserved. (c) 2017 UICC.