Abstract：
Pregnancy associated breast cancer (PABC) is defined as a breast cancer diagnosed during gestation, lactation or within 5 years postpartum. While the development of malignancy during pregnancy is rare, the incidence is increasing. Breast cancer is one of the most common cancers diagnosed during pregnancy, affecting up to 1 in 3000 deliveries. New understanding of the pathophysiology of PABC recently resulted in updated definitions distinguishing breast cancer diagnosed during pregnancy (PrBC) from cancer diagnosed during the postpartum period (PPBC) due to distinct biology and prognosis. Pregnancy has a dual effect on breast cancer development- both protective against cancer and promoting tumor growth. While several hypotheses have been proposed over the years to explain these effects, the most likely hypothesis for the development of PABC is the involution hypothesis, proposing that remodeling programs activated in the immediate postpartum period are similar to wound healing and inflammation that may be associated with tumor development and progression. Although PABCs reflect all subtypes of breast carcinomas, they are most commonly invasive ductal carcinomas of high tumor grade and large tumor size, with more advanced stage at presentation and higher rates of lymph node involvement. Most PABCs are hormone negative tumors (triple negative or HER2 amplified tumors) with high Ki-67 proliferation rates. Several studies have shown that PABCs have different genomic signatures than non-PABC tumors, showing increased expression of immune response mediators. Better understanding of the molecular pathways of tumor initiation and progression, along with prompt diagnosis and novel treatment protocols in the care of PrBC and PPBC are needed to improve outcomes for these young, high-risk breast cancer patients.
摘要：
妊娠相关乳腺癌（PABC）定义为在妊娠期间诊断出的乳腺癌，哺乳期或产后5年内。虽然怀孕期间恶性肿瘤的发展是罕见的，发病率正在增加。乳腺癌是怀孕期间最常见的癌症之一，影响高达1的3000交付。对PABC病理生理学的新理解最近导致了由于不同的生物学和预后而将妊娠期诊断的乳腺癌（PrBC）与产后诊断的癌症（PPBC）区分开的最新定义。怀孕对乳腺癌的发展有双重影响-既可以预防癌症又可以促进肿瘤生长。虽然多年来已经提出了几个假设来解释这些影响，PABC发展最可能的假设是对卷假说，建议在产后立即激活的重塑计划类似于伤口愈合和炎症，可能与肿瘤的发展和进展有关。虽然PABC反映了乳腺癌的所有亚型，它们最常见的是高肿瘤等级和大肿瘤大小的浸润性导管癌，临床分期较高，淋巴结受累率较高。大多数PABC是具有高Ki-67增殖率的激素阴性肿瘤(三阴性或HER2扩增肿瘤)。一些研究表明，PABC与非PABC肿瘤具有不同的基因组特征。显示免疫应答介质的表达增加。更好地了解肿瘤发生和发展的分子途径，在PrBC和PPBC的护理中需要及时诊断和新的治疗方案，以改善这些年轻人的预后，高危乳腺癌患者。
