Modifiable cancer risk factors and their association with hereditary cancer awareness and knowledge, and attitudes toward genetic cancer testing: a cross-sectional survey among German primary care patients

This cross-sectional study described the association between modifiable cancer risk factors and hereditary cancer awareness and knowledge, and attitudes toward genetic cancer testing among German primary care patients. Systematically recruited patients (≥18 years) from six general practices in one federal state (Mecklenburg-Western Pomerania) participated in a survey (n = 479, 67.0% participation). Analysis included those with complete data (n = 424; mean age: 53.7; 34.4% male). Weighted multiple regressions examined associations of modifiable risk factors (BMI, smoking status, past month alcohol use, and physical activity) with the outcomes, adjusting for sociodemographics. As a sensitivity analysis, regression models were stratified by personal cancer history. In the total sample, occasional compared to daily smokers reported significantly higher awareness of genetic counseling [odds ratio = 2.59, 95% confidence interval (CI): 1.03-6.51]. Higher BMI was significantly associated with higher mean importance ratings of concerns about genetic cancer testing (coef. = 0.02, 95% CI: 0.003-0.04; β = 0.12). Patients with a personal cancer history showed broader and, in some cases, stronger associations than those without. For example, significantly lower hereditary breast and ovarian cancer knowledge in daily smokers was observed only in this group. In the total sample, 44% of patients did not consider lifestyle a risk factor for breast or ovarian cancer, and 33% did not consider genetic cancer testing to be a potential facilitator for lifestyle changes. Patients at higher cancer risk from modifiable risk factors are partly less informed about hereditary cancer, though sociodemographics also contributed substantially.