Exemestane as primary treatment of oestrogen receptor-positive breast cancer in postmenopausal women: a phase II trial

To assess the efficacy of exemestane as neoadjuvant treatment, 55 postmenopausal women (mean age: 76 years; range: 66–86) with oestrogen-positive non-metastatic breast tumour and ineligible for conservative surgery were recruited into this phase II trial to receive oral exemestane (25 mg day(−1)) for 6 months. Tumour response was evaluated by clinical examination, mammography and breast ultrasound every 2 months (RECIST criteria). Overall clinical response to treatment was observed in 33/54 patients (61.1%; 95% CI: 48.1–74.0). Radiological responses in 45 evaluable patients were partial response in 23, stable disease in 21 and disease progression in one. Median time to surgery from the commencement of treatment was 7 months; conservative surgery in 24 patients (55.8%) and mastectomy in 19 patients (34.5%); no surgery (patient choice or considered not suitable by attending physician) in 12 patients. Pathologic complete response was observed in breast and axilla in one patient (2.3%) and different forms of persistent disease in 23 (53.5%) patients. Treatment tolerance was good. No patient withdrew from the study because of toxic events. We conclude that exemestane as a primary treatment is feasible and very active in elderly patients with large-sized breast cancer tumour. Conservative surgery is feasible in responding patients. No severe adverse events were detected. The optimal hormonal treatment schedule remains to be determined.