Department of Medicine, St Rita's Medical Center, Lima, OH, USA.
Cancer Manag Res. 2014 Apr 16;6:191-203. doi: 10.2147/CMAR.S60006. eCollection 2014.
Women are more likely to develop cancer in the left breast than the right. Such laterality may influence subsequent management, especially in elderly patients with heart disease who may require radiation therapy. The purpose of this study was to explore possible factors for such cancer laterality.
In this work, clinical data for consecutive patients with histologically confirmed breast cancer were reviewed, with emphasis on clinical presentation and family history.
Between 2005 and 2012, 687 patients with breast cancer were seen. Two women with incomplete data and eleven men were excluded. In total, 343 (50.9%) patients presented with left breast cancer, 311 (46.1%) with right breast cancer, and 20 (3.0%) with simultaneous bilateral malignancy. There were no significant differences between the three groups, especially in regards to clinical presentation and tumor characteristics. A total of 622 (92.3%) patients had unilateral primary, 20 (3.0%) had simultaneous bilateral, and 32 (4.7%) had metachronous primary breast cancer with subsequent contralateral breast cancer after 7.5-236 months. The worst 10-year survival was for bilateral simultaneous (18%) compared with unilateral (28%) and metachronous primaries (90%). There were no differences in survival in relation to breast cancer laterality, handedness, and presence or absence of a family history of cancer. There were significant similarities between patients and first-degree relatives in regards to breast cancer laterality, namely same breast (30/66, 45.5%), opposite breast (9/66, 13.6%), and bilateral cancer (27/66, 40.9, P=0.01163). This was more evident among patients and their sisters (17/32, 53.1%) or mothers (11/27, 40.7%, P=0.0689). There were also close similarities in relation to age at initial diagnosis of cancer for patients and their first-degree relatives for age differences of ≤5 years (48/166, 28.9%), 6-10 years (34/166, 20.5%), and >11 years (84/166, 50.6%, P=0.12065).
High similarities between patients and their first-degree relatives in regards to cancer laterality and possibly age at initial diagnosis of cancer may suggest an underlying inherited genetic predisposition.
女性罹患左侧乳腺癌的可能性高于右侧。这种侧别差异可能会影响后续的治疗，特别是对于患有心脏病、可能需要接受放射治疗的老年患者。本研究旨在探索这种乳腺癌侧别差异的可能影响因素。
本研究回顾了连续就诊的经组织学证实为乳腺癌的患者的临床资料，重点关注临床特征和家族史。
2005 年至 2012 年间，共诊治了 687 例乳腺癌患者。剔除了 2 例资料不全的患者和 11 例男性患者。共 343 例（50.9%）患者为左侧乳腺癌，311 例（46.1%）为右侧乳腺癌，20 例（3.0%）为双侧同时性恶性肿瘤。三组之间无显著差异，尤其是在临床特征和肿瘤特征方面。622 例（92.3%）为单侧原发性乳腺癌，20 例（3.0%）为双侧同时性乳腺癌，32 例（4.7%）为单侧原发性乳腺癌，7.5-236 个月后对侧乳房发生乳腺癌。双侧同时性乳腺癌的 10 年生存率最差（18%），单侧乳腺癌（28%）和对侧乳腺癌（90%）生存率较高。乳腺癌侧别、利手习惯、家族史与生存率均无显著相关性。在乳腺癌侧别方面，患者与其一级亲属之间存在显著的相似性，同侧乳房（30/66，45.5%）、对侧乳房（9/66，13.6%）和双侧乳腺癌（27/66，40.9%，P=0.01163）。患者与其姐妹（17/32，53.1%）或母亲（11/27，40.7%，P=0.0689）之间的这种相似性更为明显。在患者与其一级亲属的癌症初诊年龄方面，年龄差异在 5 岁以内（48/166，28.9%）、6-10 岁（34/166，20.5%）和 11 岁以上（84/166，50.6%，P=0.12065）也有相似之处。
患者与其一级亲属在癌症侧别和可能的癌症初诊年龄方面存在较高的相似性，这可能提示存在潜在的遗传性易感性。
