Clinical Characteristics of Patients with Metastatic Breast Cancer with Complete Remission Following Systemic Treatment

BACKGROUND: Patients with metastatic breast cancer (MBC) have variable clinical courses. The purpose was to describe the clinical characteristics of MBC patients with complete remissions (CR) following systemic treatment. METHODS: We analyzed 315 consecutive MBC patients treated with several types of systemic treatments at the National Cancer Center Hospital between January 1988 and December 1993. RESULTS: The median survival time (MST) and median progression-free survival were 28.0 and 17.1 months, respectively. Forty patients were defined as 'first-CR' following initial or second-line systemic treatment and the majority of them had a good performance status, low number of metastatic sites and low incidence of liver involvement. Nine of 40 patients with first-CR continued progression-free 5 years after beginning systemic treatments. The major sites of metastasis were the lung and bone and there were no cases with liver metastasis. Five patients received standard doxorubicin-containing combination chemotherapy with or without tamoxifen. Two of these nine patients remain progression free in first-CR. Three of them remained in first-CR after 5 years and died of progressive breast cancer and two others died of unrelated causes. Two patients relapsed after obtaining a first-CR for at least 5 years and remain alive with active metastatic disease. The MST and median progression-free survival of nine patients were 10.6 and 9.0 years, respectively. These nine patients represented 22.5% of all first-CR patients and 3.2% of the total patients. CONCLUSIONS: Although MBC is commonly recognized to be an incurable disease, a small percentage of patients clearly are alive and progression free for prolonged periods after initiation of systemic treatments.