Background The aim of this study was to determine the role of surgery in elderly patients with breast cancer. Methods Between 1999 and 2009, 153 consecutive women, ≥80 years old with breast cancer were treated at our hospital. Surgically and non-surgically treated patients were compared with respect to characteristics and survival. Results Treatment was surgical in 102 patients (67%). The non-surgically treated patients were older than surgically treated patients, had more co-morbidity and were more often diagnosed with a clinically T3/T4 tumour and distant metastasis. Patients not receiving surgery, had an 11% overall survival rate at 5-year versus 48% in surgically treated patients (P < 0.001). Independent factors for survival were clinical N0 status, M0 status at presentation and surgery. Conclusion One in three patients of 80 years and older did not have surgical treatment for breast cancer. Patient not treated surgically are older, have more severe co-morbidity and are diagnosed with more advanced disease than patients who underwent surgery.The selection of patients, who have a poor prognosis, is made on clinical grounds not measurable with a common co-morbidity survey. Better and evidence-based selection criteria for surgical and non-surgical treatment in these patients are needed.