Breast radiotherapy as part of loco-regional treatments in stage IV breast cancer patients with oligometastatic disease

BackgroundLocal treatments seem to improve metastasis progression-free survival (MPFS) and overall survival (OS) when added to systemic therapies in stage IV breast cancer.MethodsFrom 1990 to 2003, we reviewed 9138 cases treated and registered in the Institut Gustave-Roussy breast cancer database. Among them, 308 had presented with stage IV disease. Eighty percent of patients (n = 239) had received a loco-regional treatment and they were categorized into two groups: loco-regional radiotherapy (LRRT) alone (Group 1; n = 147) or breast and axillary surgery ± LRRT (Group 2; n = 92).ResultsThe median follow-up was 6.5 years. LRRT obtained a long-standing loco-regional clinical response in 85% of patients. The 3-year MPFS rates were 20% in Group 1 and 39% in Group 2; the 3-year OS rates were 39% and 57%, respectively. However, no significant differences in MPFS or OS were observed between the two groups when adjusted on prognostic factors.ConclusionsRadiation therapy alone provides long-standing local control and yields MPFS and OS rates equivalent to those obtained when radiation therapy is combined with surgery, whatever the prognostic factors. Loco-regional therapies, especially radiation therapy alone, may have an important role to play in the treatment of selected patients with stage IV breast cancer.