Underreporting Of Cancer Cases From Veterans Affairs Facilities Led To Lower Apparent Cancer Incidence Trends

A policy change at the VA resulted in underreporting of newly diagnosed cancer cases in some of the Surveillance, Epidemiology and End Results (SEER) population-based cancer registries.

To quantify the impact of the underreporting on the 2005 cancer incidence rates and long term trends, Nadia Howlader and colleagues of the National Cancer Institute in Bethesda, Md., estimated the number of missing VA cancer cases in 2005 based on a variety of factors.

Among the top ten cancers, the proportion of cancers missing in the 2005 SEER database ranged from 2.5 percent for liver cancer to 0.4 percent for melanoma. The missing data had a modest impact on long-term incidence trends with the largest impact among black males.

"Adjusting the data to include estimates of missing VA cancer cases may lead to more accurate assessment of current SEER incidence trends," according to the authors. "In reporting cancer trends, a change of as little as 1 percent per year demonstrates improvements or causes alerts in cancer control efforts," the authors write. "Such changes could easily be obscured by incomplete reporting of VA hospital data. Trends for black males in particular could be underestimated severely in the future."

The research is published in the March 24 online issue of the Journal of the National Cancer Institute.