Trends in childhood cancer incidence and mortality in urban Shanghai, 1973-2005

Abstract

Background: To describe trends in cancer incidence and mortality among children less than 15 years of age in urban Shanghai between 1973 and 2005.

Procedure: Annual rates of cancer incidence were calculated per 1,000,000 children for 3-year intervals between 1973 and 2005. Linear regression models were used to analyze the annual percent change (APC) in incidence and mortality across these distinct intervals.

Results: For all cancers combined, the incidence rate during the observed time period did not substantially change in urban Shanghai. Rates for the incidence of individual cancer did exhibit variations. Leukemia incidence remained relatively stable but the incidence of myeloid leukemia decreased sharply in both males (APC -8.6%) and females (APC -9.5%). The rate of NHL varied little among males with APC 2.1% and modestly increased among females with APC 9.3%. Anatomic sites that only occasionally demonstrate malignancy, bone and joints in males and endocrines in females, showed upward trends in incidence. A significant reduction in liver cancer incidence in males was observed. Examining mortality rates, all cancer mortality decreased by -6.0% annually in males and by -3.9% in females. This trend was mainly due to the reduction in mortality for leukemia, particularly the myeloid subtype, which decreased in males (APC -7.2%) and females (APC -7.3%).

Conclusions: Childhood cancer incidence rates showed no substantial changes but mortality demonstrated a dramatic reduction during the observed time period, suggesting an improvement in both childhood cancer diagnosis and treatment.