Missing information in statewide and national cancer databases: Correlation with health risk factors, geographic...

The objectives of this study were to analyze factors associated with outcomes and missing data in women with epithelial ovarian cancer using institutional, state and national databases.

Data were abstracted from the University of Virginia cancer registry, Virginia Department of Health (VDH) database, and Surveillance, Epidemiology, and End Results (SEER) Program and analyzed for correlations with demographics, cancer characteristics, and outcomes. Statewide spatial associations between health risk factors such as smoking, obesity, and missing grade/stage were evaluated using bivariate LiSA in Geoda.

There were 524 institutional, 3544 VDH, and 44,464 SEER cases of epithelial ovarian cancer. Institutional cases were younger, most often of white race, had increased grade 1, and decreased unknown grade and stage (all p < 0.001). Significant predictors of unknown grade were non-white race, older age, no surgery, unknown stage/stage IV, and unknown histology/adenocarcinoma. Unknown grade correlated with a significant survival disadvantage. Missing stage and grade correlated with county-level obesity and smoking, as rural regions in Southwest and Southside Virginia had high rates of health risk factors and missing stage/grade compared to urban, affluent regions in Northern Virginia.

Over a third of nationally reported cases have an unknown grade and 10-20% have an unknown stage which correlates with the worst survival. Predictors of unknown grade include insurance, age, race, smoking status, obesity, and rural setting. Missing data may represent geographical differences or disparities in cancer care available as significantly fewer cases had an unknown grade/stage at a tertiary academic medical center compared to VDH and SEER.