Patterns and trends of HPV-related cancers other than cervix in South Africa from 1994-2013.

BACKGROUND: HPV infection causes several cancers which include cervical, vaginal, vulval, penile and oropharyngeal cancer (OPC). Understanding the burden of HPV-related cancers is important for guiding cancer prevention and treatment interventions.

METHODS: To inform policy, we analysed trends of age-standardised incidence (ASIR) and mortality (ASMR) rates for HPV-related head and neck (HNC) and anogenital cancers (AGC) in South Africa between 1994 and 2013.

RESULTS: A total of 1 028 330 incident cancers and 617 044 cancer-related deaths were reported during the study period. The overall ASIR (-5.5%) and ASMR (-2.2%) for HNC declined, in part related to the anti-smoking legislation. In contrast, incidence (2.9%) and mortality (0.8%) rates for AGC increased with the rising HIV prevalence. ASIR for oral cavity cancer (OCC: -6.3%) and laryngeal cancer (LC: -11.3%) declined, including mortality associated with these cancers (OCC:-1.9%, and LC:-2.6%). However, oropharyngeal cancer showed a slower rate of decline in ASIR (-4.4%) and ASMR did not change. Compared to women, ASIR and ASMR for HNC were 3-fold higher among men. ASIR for both anal (7.5%) and vulval cancer (16.1%) increased. Median age at diagnosis of vulval cancer declined by 18 years (p-value = 0.01). Mortality rates for anal (3.9%) and vulval (2.6%) cancer increased. ASIR (-3.2%) and ASMR (-2.0%) for penile cancer declined. Rates for vaginal cancer did not change.

CONCLUSIONS: Anal and vulval cancers have increased over the reporting period. There is need to continuously monitor trends of these cancers. Implementation of HPV vaccination could significantly reduce the burden of HPV-related cancers.