Biology of primary breast cancer in older women treated by surgery: with correlation with long-term clinical outcome and comparison with their younger counterparts

Abstract

Background:As age advances breast cancer appears to change its biological characteristics, however, very limited data are available to define the precise differences between older and younger patients.Methods:Over 36 years (1973–2009), 1758 older (⩾70 years) women with early operable primary breast cancer were managed in a dedicated clinic. In all, 813 underwent primary surgery and 575 good quality tumour samples were available for biological analysis. The pattern of biomarkers was analysed using indirect immunohistochemistry on tissue microarrays. Comparison was made with a previously characterised series of younger (<70 years) patients.Results:There was high expression of oestrogen receptor (ER), PgR, Bcl2, Muc1, BRCA1 and 2, E-cadherin, luminal cytokeratins, HER3, HER4, MDM2 and 4 and low expression of human epidermal growth factor receptor (HER)-2, Ki67, p53, EGFR and CK17. Oestrogen receptor and axillary stage appeared as independent prognostic factors. Unsupervised partitional clustering showed six biological clusters in older patients, five of which were common in the younger patients, whereas the low ER luminal cluster was distinct in the older series. The luminal phenotype showed better breast cancer-specific survival, whereas basal and HER2-overexpressing tumours were associated with poor outcome.Conclusion:Early operable primary breast cancer in older women appears as a distinct biological entity, with existence of a novel cluster. Overall older women showed less aggressive tumour biology and ER appeared as an independent prognostic factor alongside the time-dependent axillary stage. These biological characteristics may explain the differences in clinical outcome and should be considered in making therapeutic decisions.

Tumor biology in older breast cancer patients – What is the impact on survival stratified for guideline adherence? A retrospective multi-centre cohort study of 5378 patients

“…Both authors published similar results using the intrinsic classification. Also within the biological subgroup further differences between the age groups have been described by several other authors [15,16]. These results should be considered for future treatment recommendations.…”

Distinct Postsurgical Management in Young and Elderly Breast Cancer Patients Results in Equal Survival Rates

“…Previous reports have demonstrated that aging is associated with less aggressive tumor features and higher rates of hormonal responses (Downey et al, 2007;Passage and McCarthy, 2007;Thomas and Leonard, 2009;Syed et al, 2013;Thapa et al, 2013;Wei et al, 2014). In the present study, most (74%) elderly BC patients were hormone receptor-positive.…”

Management of Operable Primary Breast Cancer in Older Women

“…However, in older frail patients, or those with a number of comorbidities and limited life expectancy and also those with a number of social issues, surgery may not be the appropriate Reproduced from [9]. Management of operable primary breast cancer in older women Review answer.…”

“…Definitions of the older population in these studies also vary, for example, using postmenopausal status or age at diagnosis as cut-offs (55, 60, 65 and 70 years). The authors' group has also attempted to compare the biology of breast cancers in younger versus older women managed in one single institution and using the same laboratory methodology [9]. Not only was a changing pattern with age shown but also a new cluster with distinct biological pattern ('low ER luminal') has been identified in the older cohort (Figures 1 & 2).…”