Sheppard Amanda J, Chiarelli Anna M, Hanley Anthony J G, Marrett Loraine D
Indigenous Cancer Care Unit, Prevention and Cancer Control, Cancer Care Ontario, Toronto, Ontario, Canada.
Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
JCO Glob Oncol. 2020 Feb;6:99-107. doi: 10.1200/JGO.19.00061.
Survival after a breast cancer diagnosis is poorer in First Nations women with a preexisting comorbidity compared with comorbidity-free First Nations women in Ontario, Canada. Given the high prevalence of diabetes in this population, it is important to determine whether preexisting diabetes is related to poorer survival after a breast cancer diagnosis.
All First Nations women were identified from a cohort of First Nations people diagnosed with breast cancer in diagnostic periods-1995 to 1999 and 2000 to 2004-and seen at a regional cancer program (RCP) in Ontario. Preexisting diabetes status and other factors, such as age at diagnosis, body mass index, and stage at diagnosis, were collected from medical charts at the regional cancer programs. The association between preexisting diabetes and First Nations status was examined by each of the demographic, personal, tumor, and treatment factors using logistic regression models. Survival was compared between First Nations women with (n = 67) and without (n = 215) preexisting diabetes, adjusted by significant study factors using a Cox proportional hazards regression model.
The 5-year survival rate among First Nations women with diabetes was 59.8% versus 78.7% among those without diabetes ( < .01). Preexisting diabetes significantly increased the risk of death among First Nations women with breast cancer (hazard ratio, 1.87; 95% CI, 1.12 to 3.13) after adjustment for age group, period of diagnosis, body mass index, other comorbidities at diagnosis, and stage.
This study recommends awareness of this survival discrepancy among the treatment team for First Nations patients with breast cancer with preexisting diabetes.
与加拿大安大略省无合并症的原住民女性相比，患有合并症的原住民女性在被诊断出患有乳腺癌后的生存率更低。鉴于该人群中糖尿病的高患病率，确定糖尿病是否与乳腺癌诊断后的较差生存率相关非常重要。
从1995年至1999年以及2000年至2004年诊断期内被诊断患有乳腺癌且在安大略省的一个区域癌症项目（RCP）就诊的原住民人群队列中识别出所有原住民女性。从区域癌症项目的病历中收集糖尿病既往病史以及其他因素，如诊断时的年龄、体重指数和诊断分期。使用逻辑回归模型，通过人口统计学、个人、肿瘤和治疗因素分别检验糖尿病既往病史与原住民身份之间的关联。使用Cox比例风险回归模型，在调整显著研究因素后，比较有（n = 67）和无（n = 215）糖尿病既往病史的原住民女性的生存率。
患有糖尿病的原住民女性的5年生存率为59.8%，而无糖尿病的女性为78.7%（P <.01）。在调整年龄组、诊断时期、体重指数、诊断时的其他合并症和分期后，糖尿病既往病史显著增加了患有乳腺癌的原住民女性的死亡风险（风险比，1.87；95% CI，1.12至3.13）。
本研究建议乳腺癌合并糖尿病的原住民患者的治疗团队了解这种生存差异。
