Patterns of relapse and modalities of treatment of breast cancer: the 'IRIS' Project, a multicenter observational...

The aim of this study was to describe the patterns of breast cancer relapse and the factors influencing therapeutic choices in an unselected postmenopausal population.

Five hundred and thirty-nine patients were enrolled between October 1999 and March 2001. The majority (92.6%) underwent surgery for the primary tumor: there was no difference between general and university hospitals in terms of the type of mastectomy, but a slight difference was found between Southern and Northern Centers.

At the time of first relapse, 61.6% of the patients had a good Karnofsky performance status. The median disease-free interval (DFI) was 34 months. More than half of the patients (62.3%) presented a single metastasis. Metastatic disease was treated with chemotherapy in 64.8% of cases (alone in 44.1%, and in combination with hormone therapy in 20.1%), hormone therapy alone was given in 30.8% of cases. The main reasons for choosing chemotherapy were age (31%), standard guidelines (19.4%) and the site of metastatic disease (14.3%), and those for selecting hormone therapy were age (26.6%), site of relapse (19.3%), standard guidelines (19.2%), biological tumor characteristics (14.3%) and the DFI (11.1%). Taxane-containing treatments accounted for 46.1% of the chemotherapies, whereas letrozole was the preferred hormone (41.2%).

The first relapse of breast cancer is often single, at bone or viscera, and mainly diagnosed by instrumental screening examinations. The preferred chemo- and hormone therapies are taxane-containing regimens and letrozole, respectively.