1999). The NCCN (2005) has published guidelines on cancer-related fatigue in clinical practice (Figure 3-4).

Cognitive Effects

Cognitive dysfunction has been observed among breast cancer survivors treated with adjuvant chemotherapy (Ganz, 1998; Meyers, 2000; Brezden et al., 2000; Ahles and Saykin, 2002; Rugo and Ahles, 2003; Saykin et al., 2003; Phillips and Bernhard, 2003; Tannock et al., 2004; Wefel et al., 2004a,b). The cognitive dysfunction, sometimes called “chemobrain,” includes deficits in memory, concentration, and executive functioning.22 Such dysfunction can impede attainment of work, education, and general quality of life goals. Underlying mechanisms are unknown, but recent evidence indicates that some degree of cognitive impairment exists prior to chemotherapy, suggesting that the disease itself rather than the treatment may be responsible (Wefel et al., 2004a). In their review of baseline measurements taken as part of three clinical trials, Wefel and colleagues found that 35 percent of women exhibit cognitive impairment before the start of systemic therapy for breast cancer. According to this review, distress was found to be significantly related to cognitive impairment. Other preliminary studies suggest there may be a genetic predisposition to susceptibility to chemotherapy-associated cognitive decline (Ahles et al., 2003). In order to understand its onset and underlying mechanisms, longitudinal studies of cognitive function are needed as well as studies of interventions designed to alleviate such dysfunction.

Risk to Family Members

Approximately 5 to 10 percent of breast cancer is hereditary and accounted for by mutations in the BRCA1 and BRCA2 genes. The likelihood that a woman with breast cancer has a BRCA mutation is estimated at 1 in 50 in women who are not Ashkenazi Jewish, and 1 in 10 in Ashkenazi Jewish women (NCI, 2004b). Only women with family histories or a personal history of breast cancer at a young age are candidates for BRCA testing (NCCN, 2004e). ASCO guidelines recommend that genetic testing only be offered to selected patients with personal or family histories suggestive of a hereditary syndrome, in the context of pre- and post-test counseling to discuss the risks and benefits of genetic testing and cancer early detection and prevention methods, and only when the test results can be

22  

Executive functioning refers to the brain’s supervisory or regulatory functions.



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