Validation of family cancer history data in high-risk families: the influence of cancer site, ethnicity, kinship degree, and multiple family reporters.

Information on family cancer history (FCH) is often collected for first-degree relatives, but more extensive FCH information is critical for greater accuracy in risk assessment. Using self-reported diagnosis of cancer as the gold standard, we examined differences in the sensitivity and specificity of relative-reported FCH by cancer site, race/ethnicity, language preference, and kinship degree (1,524 individuals from 557 families; average number of relatives per family = 2.7). We evaluated the impact of FCH data collected in 2007-2013 from multiple relatives by comparing mean values and proportions for the number of relatives with any cancer, breast cancer, or ovarian cancer as reported by a single relative and by multiple relatives in the same family. The sensitivity of FCH was lower in Hispanics, Spanish-speaking persons, and third-degree relatives (e.g., for all cancers, sensitivities were 80.7%, 87.4%, and 91.0% for third-, second-, and first-degree relatives, respectively). FCH reported by multiple relatives included a higher number of relatives with cancer than the number reported by a single relative (e.g., mean increase of 1.2 relatives with any cancer), with more relatives diagnosed with any cancer, breast cancer, and ovarian cancer in 52%, 36% and 12% of families, respectively. Collection of FCH data from multiple relatives may provide a more comprehensive picture of FCH and may potentially improve risk assessment and preventive care.