Trends in Incidence and Mortality Rates of Squamous Cell Carcinoma and Adenocarcinoma of Cervix - Worldwide

The objective of the present paper is to summarize and quantify the trends in incidence and mortality ratesof cervical squamous cell carcinoma (SCC) and adenocarcinoma (AC) worldwide. All indexed publications,which provided information on time trends in incidence or mortality rates of cervix cancer, published duringthe past 12 years were included. The details of studies have been identified through searches on the MEDLINEdatabase. Cytology screening as well as changes in socio-economic profile has led to declines in cervical SCCincidence and mortality rates worldwide. Higher percentage decline in SCC is observed in countries whereorganized screening programmes are available. The results suggested that Pap smear screening has played asignificant role in the reduction in SCC in the US, Canada, New South Wales, and in almost all Europeancountries (except in Ireland) as well as in some of the Asian countries. Increasing incidence and mortality ratesof cervical AC has reported in many countries such as the US, Canada, UK, Iceland, Sweden, England, Spain,Finland, Slovakia, Slovenia, the Netherlands particularly among young women. However the increase was mainlyin earlier periods till 1995 and stable or declining trends in cervical AC have been observed in later periods inmany of the above countries such as the US, UK, Canada, Sweden. The increasing risk of AC suggested a majorrole for an increasing prevalence of persistent oncogenic HPV infection and its cofactors, whereas the downturnin period effects in several countries during the 1990s provided evidence that cytology screening is detectingmore preinvasive ACs than in previous decades and suggested that screening might be starting to have a protectiveimpact on AC. The decline in AC incidence might be due to improved specimen collection as well as due toincreased awareness of AC pre-cursors among cytopathologists and clinicians, improvements in laboratorytraining and quality assurance. In conclusion, cytology screening in combination with HPV screening for highriskHPV types may maximize the possibilities of having early cervical lesions detected and treated.