The role of proton beam therapy in the management of elderly breast cancer patients

In 2019, an estimated 268,600 women will be diagnosed with breast cancer in the United States making breast cancer responsible for 30% of new female cancer diagnoses (1). Breast cancer prevalence increases dramatically with age such that an American woman over age 70 has a one out of fifteen probability of receiving a new breast cancer diagnosis (1). Elderly women tend to present with more favorable breast tumors: smaller tumor sizes, higher steroid receptor expression, lower rates of proliferation, less poorly differentiated and fewer nodal metastases (2-4). Despite their more favorable tumor characteristics, breast cancer carries a worse prognosis in this population regardless of cancer stage (5,6). Co-morbid conditions play a role in the decrease in overall survival (OS) with advancing age (7-9), but breast cancer disease-specific survival (DFS) is also worse in elderly patients (5). This may possibly be due to an inability to tolerate aggressive therapy for locally advanced disease