F51Adjuvant endocrine therapy in elderly patient in early Breast Cancer, a less toxic therapy, is it really true? A single institution, “real life” experience

Background: Approximately 25% of cases of breast cancer (BC) occur in women over 75 years of age. These patients (pts) are poorly represented in studies and often present comorbidities, that could complicate therapeutic decision. Patients and methods: Between 2003 to 2016 we retrospectively identified 100 pts at our Institution with BC over 75 years of age. Among them we analysed clinical and pathological data of 57 pts with early BC who underwent to endocrine therapy (HT). Results: Gender: 1 men and 56 women. Median age at first diagnosis 78 years (range 75-87) Performance Status (PS): 46 pts (59%) had PS 0, 30 pts (39%) had PS 1, 2 pts (2%) had PS 2; Histology: 46 ductal carcinoma, 9 lobular, 1 mucinous, 1 papillary. Stage at first diagnosis: 28 Stage I, 21 Stage II, 8 Stage III. Molecular subtype: 42 Luminal A, 9 Luminal B (7 Her2 positive, 2 HER2 negative), 6 HER2 positive. Comorbidities at baseline were evaluated: 25 (43%) had hypertension, 16 (28%) showed a previous cardiovascular event, 11 (19%) had osteoporosis; 6 (10%) had mood disorders and anxiety. 18 pts (31%) had at least 3 comorbidities. 15 (26%) were taking at least 3 concomitant medications. 6 pts received adjuvant chemotherapy; among them 5 pts received trastuzumab, one patient interrupted anti-HER2 therapy for reduction of the ejection fraction >20% points. Type of HT: 54 aromatase inhibitors (AI), 2 tamoxifene (TAM) and 1 switch therapy. 36 (63%) pts experienced side effects: 22 pts developed osteoporosis and 1 pt had a vertebral collapse, 27 had bone and joint pain: 22 pts of G1 and G2, 5 pts of G3 and G4; 1 pt developed a mood disorder, 1 pt hypertension, 1 pt developed atrial fibrillation, 1 pt had angina,1 pt had a transient ischemic attack, 1 pt has dyslipidemia, 1 pt developed cefalea, 1 pt developed hyperglicemia. 11 pts interrupted treatment for side effects: 1 patient experienced a TIA, 1 a worsening of ostoporosis, 1 a drug hypersensitivity, 8 pts disabling bone and joint pain; 4 pts interrupted treatment for progressive disease. Conclusions: Our preliminary retrospective data suggest that elderly pts develop more side effects than those reported in studies of adjuvant HT; therapeutic decision should not be based only on tumor characteristics but also on patient's characteristics.