Patterns of local and distant disease relapse in patients with breast cancer treated with primary chemotherapy : do patients with a complete pathological response differ from those with residual tumour in the breast?

This study aimed to evaluate patterns of local and distant disease recurrence in patients having primary chemotherapy and compared patterns of relapse in patients with a complete pathological response with those who had residual breast disease. This is an observational study using a sequential series of patients treated with primary chemotherapy. They were followed up for a minimum of 5 years. All data was collected prospectively. Three hundred forty-one consecutive patients with breast cancer were treated with up to eight cycles of doxorubicin-based chemotherapy. Clinical and pathological response rates were evaluated and patients were followed up for disease recurrence (local and distant) and overall survival. Fifty-two patients (16.5%) had a complete pathological response to chemotherapy. Distant disease recurrence occurred in nine patients (17.3%) but no local recurrence was observed. In patients not having a complete pathological response, 86 patients (32.6%) subsequently developed metastases. Local recurrence of disease occurred in 12 (4.5%). There was a statistically significant difference in overall survival between patients whose tumours had a complete pathological response compared with patients who had residual disease in the breast following chemotherapy (88% versus 70% at 5 years, p = 0.036). Following primary chemotherapy, about 84% of patients had residual disease in the breast. Surgery is necessary to ensure complete removal of residual tumour and excellent rates of local control are achievable. A complete pathological response is associated with fewer local and distant recurrences as well as improved survival although there are no differences in time to development of metastatic relapse.