Referral models (ten studies, five referral models were identified): Sensitivity and specificity varied depending on the population in which the models were assessed. Estimates were high (sensitivity between 87 and 100%) in studies conducted in primary care screening populations. Populations with higher prevalence of BRCA carriers showed lower sensitivity.
Genetic counselling (27 studies): Several studies reported decreased intentions to participate, or actual participation in screening following genetic counselling. Breast cancer-related worry either decreased or did not change following counselling; no studies reported increases. Where reported, measures of anxiety and depression also generally decreased or did not differ following counselling.
Genetic Testing, adverse effects (13 studies): Five studies reported significantly increased breast cancer-related worry after receipt of BRCA results. These increases were confined to mutation carriers. One study reported a decrease in breast cancer-related worry for both carriers and non-carriers. Studies reported mixed results for anxiety; some found decreases regardless of carrier status whilst others reported decreases for non-carriers and increases for carriers. Depression scores also showed varying impacts.
Risk-reducing interventions
Intensive screening (five studies): There were no studies of the effectiveness of intensive screening; five studies of intensive breast cancer screening of mutation carriers and other high-risk women reported adverse effects. These included mixed evidence but some studies showed more false positives with MRI than mammography but some indication of fewer false negatives. Recall rates for MRI were also higher in one study, mostly for benign findings. Additional unnecessary imaging procedures and biopsies were also higher in patients who had had MRI in one study. Discomfort, pain and anxiety were not generally increased by intensive yearly screening compared to usual surveillance. One study assessed ovarian cancer screening and found high levels of unnecessary diagnostic surgery (55%); 3% of screening visits detected some abnormality of which around one fifth were cancerous.
Medications (three studies): There were no trials that evaluated the efficacy of risk-reducing medications in mutation carriers. Three trials in women at various risk levels showed reduced risks for oestrogen receptor positive cancer in those treated with prophylactic tamoxifen or raloxifene. Higher rates of several categories of adverse events were reported in women in these active treatment groups, including thromboembolic events and endometrial events including cancer.
Surgery (six studies): Three studies reported the impact of bilateral mastectomies. Two found a reduced incidence of breast cancer occurred in the intervention group compared with non-operated carriers. Surgical complications were frequent. Another reported less anxiety in women after surgery but no change on other psychological measures. One study of salpingo-oophorectomy and one of oophorectomy reported reduced incidences of ovarian cancer or breast cancer (one study each). Two other small studies described some adverse effects of oophorectomy.