Differences in psychosocial variables between unaffected relatives and probands pursuing BRCA1/2 genetic counseling

A7

Although genetic counseling guidelines for probands (the first person in a family to undergo genetic testing) and relatives of BRCA1/2 mutation carriers are well established, few studies have examined differences in knowledge, distress, and risk perception between unaffected relatives and affected probands prior to the initial genetic counseling session. The purpose of this study was to examine psychosocial differences between affected probands and unaffected relatives of mutation carriers prior to undergoing genetic counseling. Participants in this study were women with a 10% or greater likelihood of carrying a BRCA mutation, including women who have been affected with breast cancer and unaffected women with a known mutation in their family. For the present analyses, we excluded women who were within a year of their cancer diagnosis (n=39) or who were diagnosed with ovarian cancer (n=18). Participants (N=206) were self- or physician-referred to cancer genetic counseling programs. Prior to genetic counseling, participants completed a telephone interview assessing breast cancer knowledge, distress, perceived BRCA1/2 mutation risk, and perceived breast and ovarian cancer risk. At baseline, relatives exhibited higher knowledge (t(205)= -2.22; p=.03) and higher perceived risk for carrying a BRCA1/2 mutation (t(199) = -4.52; p<.0001). Next, we stratified our analyses by age (< 40 or > 40) to be consistent with risk management recommendations. In younger women, probands reported significantly higher breast cancer distress than relatives (t(49) = 2.51; p=.02) and relatives reported greater perceived risk for carrying a BRCA1/2 mutation (t(47)= 1.86; p=.08). In older women, a significant difference emerged between probands and relatives on BRCA1/2 mutation risk (t(150) = -3.04, p=.003), and a trend was found for differences in breast cancer knowledge, (t(153) = -1.78; p=.08), with relatives having greater perceived risk and breast cancer knowledge than probands. Finally, we evaluated perceived risk for breast and ovarian cancer after excluding women who reported having prophylactic surgery at baseline (n = 44). Relatives reported higher perceived risk for breast cancer (t(156) = -5.49; p<.0001) and ovarian cancer t(150) = -5.10; p<.0001). These results remained significant when stratified by age (< 40 or > 40). Clinically, these results suggest that unaffected relatives of mutation carriers are entering the genetic counseling process with higher BRCA knowledge and perceived risk compared to probands, but not more distress. However, younger probands are experiencing significantly more distress, despite lower ratings of perceived risk and knowledge. These results have implications for specialized tailoring of genetic counseling sessions based on proband versus relative status and the accompanying differences in knowledge that may affect a patient’s approach to and understanding of information presented during the genetic counseling process. Genetic counselors should also routinely assess distress levels of younger probands to provide appropriate referrals and psychosocial services.