Hong Chenyan, Zheng Yiqiong, Geng Rui, Hu Huayu, Zhong Yuting, Guan Qingyu, Zhang Yanjun, Li Xiru
School of Medicine, Naikai University, Tianjin, China.
Department of General Surgery, the First Medical Center of the People's Liberation Army (PLA) General Hospital, Beijing, China.
Ann Transl Med. 2022 Jul;10(13):742. doi: 10.21037/atm-21-5400.
The incidence of bilateral breast cancer (BBC) is low, accounting for 5% of patients with breast cancer. This study aimed to investigate the clinicopathological features and prognosis of synchronous bilateral breast cancer (SBBC) and metachronous bilateral breast cancer (MBBC) in the Chinese population.
Patients with BBC, including SBBC and MBBC, were selected from 6,162 breast cancer patients who underwent surgery at the Chinese People's Liberation Army (PLA) General Hospital between January 2007 and December 2019. Furthermore, patients with unilateral breast cancer (UBC) who underwent surgery at the same time were randomly selected at a ratio of 1:2 as the control group. Clinicopathological features and prognosis were compared between the groups.
In all, 123 (2.0%) patients with BBC were enrolled in this study, including 98 (1.6%) SBBC and 25 (0.4%) MBBC patients. A total of 280 patients with UBC were selected for the control group. Compared with patients with UBC, patients with SBBC were more likely to be older and have a family history of breast cancer, non-infiltrative carcinoma, lower pathological tumor-node-metastasis (pTNM) stage, and luminal A type breast cancer as their first tumor. Patients with MBBC were more likely to be postmenopausal and have hormone receptor [estrogen receptor (ER)/progesterone receptor (PR)] negativity, a higher pTNM stage, and a triple-negative first tumor. Patients with UBC with ER/PR (-) were more likely to develop contralateral breast cancer (CBC) than those with ER/PR (+). There was no significant difference in overall survival (OS) and disease-free survival (DFS) between patients with SBBC and patients with UBC. Patients with MBBC had worse DFS than those with UBC, but OS was similar for both types of patients. Patients with MBBC <55 years at first diagnosis had significantly shorter DFS compared to those with SBBC and UBC. A multivariate Cox proportional hazards model revealed that age ≥55 years and ER/PR negativity of the first tumor were independent risk factors for OS. Independent risk factors for DFS included MBBC, age <55 years, family history of other malignant tumors, ER/PR (-), lymphovascular invasion, and N stage ≥2 of the first tumor.
The OS and DFS of patients with SBBC and UBC were similar. The MBBC patients, especially those <55 years old at first diagnosis, had shorter DFS than patients with UBC.
双侧乳腺癌（BBC）的发病率较低，占乳腺癌患者的5%。本研究旨在调查中国人群中同步性双侧乳腺癌（SBBC）和异时性双侧乳腺癌（MBBC）的临床病理特征及预后。
从2007年1月至2019年12月在中国人民解放军总医院接受手术的6162例乳腺癌患者中选取BBC患者，包括SBBC和MBBC患者。此外，同时接受手术的单侧乳腺癌（UBC）患者按1:2的比例随机选取作为对照组。比较两组的临床病理特征及预后。
本研究共纳入123例（2.0%）BBC患者，其中98例（1.6%）为SBBC患者，25例（0.4%）为MBBC患者。共选取280例UBC患者作为对照组。与UBC患者相比，SBBC患者年龄更大，更易有乳腺癌家族史、非浸润性癌、较低病理肿瘤-淋巴结-转移（pTNM）分期，且其首发肿瘤为腔面A型乳腺癌。MBBC患者更易绝经，且激素受体[雌激素受体（ER）/孕激素受体（PR）]阴性、pTNM分期更高，首发肿瘤为三阴性。ER/PR（-）的UBC患者比ER/PR（+）的患者更易发生对侧乳腺癌（CBC）。SBBC患者与UBC患者的总生存期（OS）和无病生存期（DFS）无显著差异。MBBC患者的DFS比UBC患者差，但两种类型患者的OS相似。首次诊断时年龄<55岁的MBBC患者的DFS明显短于SBBC和UBC患者。多因素Cox比例风险模型显示，年龄≥55岁和首发肿瘤ER/PR阴性是OS的独立危险因素。DFS的独立危险因素包括MBBC、年龄<55岁、其他恶性肿瘤家族史、ER/PR（-）、淋巴管浸润以及首发肿瘤N分期≥2。
SBBC患者与UBC患者的OS和DFS相似。MBBC患者，尤其是首次诊断时年龄<55岁的患者，其DFS比UBC患者短。
