Highly durable response to capecitabine in patient with metastatic estrogen receptor positive breast cancer: A case report.

In estrogen receptor-positive HER2-negative (ER+HER2-) metastatic breast cancer, chemotherapy should be offered only to patients who develop endocrine resistance or have a rapid disease progression. However, the correct sequence of chemotherapy administration is still debated. We report the case of a 49-year-old woman with ER+ HER2- metastatic breast cancer who experienced an exceptionally long response to capecitabine administered as second-line therapy following a first-line anthracycline-based chemotherapy. The patient was diagnosed with ER+ HER2- metastatic breast cancer with massive liver involvement and mediastinal lymph nodes metastasis. This patient was treated with capecitabine 1000 mg/mq bid given intermittently for 14 days within a 21-day cycle as a second-line therapy following a rapid progression on letrozole treatment given as a maintenance therapy. Our patient experienced a progression-free survival (PFS) >3 years with an exceptionally good quality of life (QoL). In ER+HER2- metastatic breast cancer patients, capecitabine monochemotherapy in second line may be associated with a particularly satisfactory PFS and no impact in terms of QoL. Future studies focused on biomarkers with predictive ability may help select patients who represent the best candidates to this treatment.