Although previous studies have suggested a higher risk of breast cancer recurrence with increasing age, older patients with early stage breast cancer generally receive less extensive treatment. The aim of this study was to evaluate the impact of older age on risk of locoregional and distant recurrence among patients aged 70 years or older in a large population based cohort.
Patients aged 70 years and older who were diagnosed with early stage breast cancer between 2003 and 2009 and underwent surgery were selected from the Netherlands Cancer Registry. Cumulative incidences of locoregional and distant recurrence according to age categories were calculated using the Cumulative Incidence Competing Risks (CIRC) method. The Fine and Gray model was used to estimate the effect of age on recurrence which was expressed as subdistribution hazard ratio (sHR). A two-step multivariable analysis was performed, the first multivariable model adjusted for patient and tumor characteristics and the second model, the full model, additionally adjusted for treatment characteristics.
Overall, 19748 patients were included. During follow-up, 832 of 7799 patients (10.7%) aged 70-74 years, 707 of 4344 patients (16.3%) aged 75-79 years and 927 of 6322 patients (14.7%) aged ≥80 years had a locoregional or distant recurrence. In univariate analysis, age 75-79 years and ≥80 years were associated with a higher risk of locoregional and distant recurrence compared to the reference age group of 70-74 years. After adjustment in the full multivariable model, the risk of distant recurrence remained significantly higher for patients aged 75-79 (sHR: 1.25, 95% CI 1.11-1.41, p = 0.001), but not for patients aged ≥80 years (sHR: 1.04, 95% CI 0.93-1.18, p = 0.483). For locoregional recurrence risk, no significant association with age was found in the multivariable analysis.
In this large population based study, patients aged 75-79 years were at increased risk of distant recurrence compared to patients aged 70-74 years. Possible explanations can be suboptimal treatment selection and different treatment response in older patients compared to younger patients.
Leiden University Medical Center.
ZonMw.
All authors have declared no conflicts of interest.