Clinicopathological features of patients with breast cancer aged 70 years or over

The risk of breast cancer (BC) increases in parallel with increasing age. Despite the increased disease burden in elderly patients, there is still a great uncertainty regarding "how to manage" BC in aging-population. The purpose of this study was to investigate the clinicopathological features and treatment approaches of patients with BC aged 70 years or over.

The medical records of 4413 patients with BC followed between 1994-2015 were retrospectively analyzed. Of the 4413 patients, 238 with stage I to III disease aged 70 years or over at BC diagnosis were enrolled into this study. Patients were divided into 2 groups according to the age as group 1 (70-79 years, N=192) and group 2 (80 or over, N=46). Clinicopathological features of patients including tumor histology, grade, estrogen (ER) and progesterone receptor (PgR) status, human epidermal growth factor receptor 2 (HER2) status, tumor size, lymph node involvement (LNI), lymphovascular invasion (LVI), perineural invasion (PNI), clinical stage, type of surgery, treatments and comorbid diseases were evaluated.

The median age was 74 for group 1 (range 70-79) and 82 for group 2 (range 80-92). Excluding tumor size and grade, no statictically significant difference was found between the two groups according to histopathological characteristics. Patients in group 2 had more commonly larger T stage (T4), and less frequently presented with grade I tumor (p=0.014 and p=0.044, respectively). Modified radical mastectomy and adjuvant chemotherapy were more commonly performed in group 1 (p=0.001 and p=0.001, respectively). In contrast, neoadjuvant treatment was more frequently applied in group 2 (p=0.003). There was no difference in disease-free survival (DFS) between the groups (p=0.012), however, median overall survival (OS) was significantly higher in group 1 (p=0.03).

Excluding the tumor grade and tumor size, both groups had similar histopathological features. However, patients aged between 70-79 years were likely to receive more agressive treatments for BC, indicating that treatment choice in patients over the age of 80 years was likely to be based on age-related factors rather than tumor characteristics.