Background:Asians are diagnosed with breast cancer at a younger age than Caucasians are.We studied the effect of age on locoregional recurrence and the survival of Asian breast cancer patients treated with breast-cons...Background:Asians are diagnosed with breast cancer at a younger age than Caucasians are.We studied the effect of age on locoregional recurrence and the survival of Asian breast cancer patients treated with breast-conserving therapy.Methods:Medical records of 2492 patients treated with breast-conserving therapy between 1989 and 2012 were reviewed.The Kaplan-Meier method was used to estimate locoregional recurrence,breast cancer-free survival,and breast cancer-specific survival rates.These rates were then compared using log-rank tests.Outcomes and age were modeled by Cox proportional hazards.Fractional polynomials were then used to test for non-linear relationships between age and outcomes.Results:Patients≤40 years old were more likely to have locoregional recurrence than were older patients(Hazard ratio[HR]=2.32,P<0.001).Locoregional recurrence rates decreased year-on-year by 4%for patients with luminal-type breast cancers,compared with 8%for those with triple-negative cancers.Similarly,breast cancer-free survival rates increased year-on-year by 4%versus 8%for luminal-type and triple-negative cancers,respectively.Breast cancer-spe-cific survival rates increased with age by 5%year-on-year.Both breast cancer-free survival and breast cancer-specific survival rates in patients with luminal cancers exhibited a non-linear(“L-shaped”)relationship-where decreasing age at presentation was associated with escalating risks of relapse and death.The influence of age on overall survival was confounded by competing non-cancer deaths in older women,resulting in a“U-shaped”relationship.Conclusions:Young Asian breast cancer patients have a continuous year-on-year increase in rates of disease relapse and cancer deaths compared with older patients with no apparent threshold.展开更多
文摘Background:Asians are diagnosed with breast cancer at a younger age than Caucasians are.We studied the effect of age on locoregional recurrence and the survival of Asian breast cancer patients treated with breast-conserving therapy.Methods:Medical records of 2492 patients treated with breast-conserving therapy between 1989 and 2012 were reviewed.The Kaplan-Meier method was used to estimate locoregional recurrence,breast cancer-free survival,and breast cancer-specific survival rates.These rates were then compared using log-rank tests.Outcomes and age were modeled by Cox proportional hazards.Fractional polynomials were then used to test for non-linear relationships between age and outcomes.Results:Patients≤40 years old were more likely to have locoregional recurrence than were older patients(Hazard ratio[HR]=2.32,P<0.001).Locoregional recurrence rates decreased year-on-year by 4%for patients with luminal-type breast cancers,compared with 8%for those with triple-negative cancers.Similarly,breast cancer-free survival rates increased year-on-year by 4%versus 8%for luminal-type and triple-negative cancers,respectively.Breast cancer-spe-cific survival rates increased with age by 5%year-on-year.Both breast cancer-free survival and breast cancer-specific survival rates in patients with luminal cancers exhibited a non-linear(“L-shaped”)relationship-where decreasing age at presentation was associated with escalating risks of relapse and death.The influence of age on overall survival was confounded by competing non-cancer deaths in older women,resulting in a“U-shaped”relationship.Conclusions:Young Asian breast cancer patients have a continuous year-on-year increase in rates of disease relapse and cancer deaths compared with older patients with no apparent threshold.