Saunders C, Vijay V, Stein J, Baum M
Department of Surgery, Royal Free and University College Medical School, London, UK.
Ann R Coll Surg Engl. 1999 Nov;81(6):393-8.
Breast cancer causes around 21,000 deaths per year in the UK, the vast majority of these occurring in women aged over 50 years with no genetic predisposition to the disease. Screening and symptomatic services for these women, although by no means perfect or homogeneous, have gradually improved over the last 10 years and, perhaps as a result of this, together with increased use of adjuvant systemic therapy, mortality in this group has fallen. Despite this reassuring state of affairs, media interest in the disease and patients' perception of their risk of developing breast cancer have risen. Part of this is undoubtedly due to the new scientific developments in cancer genetics and, in particular, identification of the BRCA1 gene in 1994 and BRCA2 gene shortly afterwards. These genes are dominantly inherited with up to 80% penetrance; thus, women (and occasionally men) inherit these genes and have a high lifetime risk of developing breast cancer, usually at a younger age than average and possibly of a more aggressive phenotype. Unaffected family members can now be screened and, if they prove carriers, screening for early detection and prevention strategies such as bilateral prophylactic mastectomy can be offered. Because of the high risk of ovarian cancer in BRCA1 carriers, screening or prophylactic ovariectomy may also be considered.
在英国,乳腺癌每年导致约2.1万人死亡,其中绝大多数发生在50岁以上且无该疾病遗传易感性的女性身上。针对这些女性的筛查和症状性服务,尽管远非完美或统一,但在过去10年中已逐渐改善,或许正因如此,再加上辅助性全身治疗的使用增加,该群体的死亡率有所下降。尽管情况令人欣慰,但媒体对该疾病的关注以及患者对自身患乳腺癌风险的认知却有所上升。部分原因无疑是癌症遗传学的新科学进展,特别是1994年BRCA1基因的鉴定以及随后不久BRCA2基因的鉴定。这些基因呈显性遗传,外显率高达80%;因此,女性(偶尔也有男性)继承这些基因后,一生中患乳腺癌的风险很高,通常发病年龄比平均水平小,且可能具有更具侵袭性的表型。现在可以对未受影响的家庭成员进行筛查,如果他们被证明是携带者,可以提供诸如双侧预防性乳房切除术等早期检测和预防策略的筛查。由于BRCA1基因携带者患卵巢癌的风险很高,也可考虑进行筛查或预防性卵巢切除术。