Prognostic factors for survival of women with unstable spinal bone metastases from breast cancer

Abstract

Background: Bone metastases are an important clinical issue in women with breast cancer. Particularly, unstable spinal bone metastases (SBM) are a major cause of severe morbidity and reduced quality of life (QoL) due to frequent immobilization. Radiotherapy (RT) is the major treatment modality and is capable of promoting re-ossification and improving stability. Since local therapy response is excellent, survival of these patients with unstable SBM is of high clinical importance. We therefore conducted this analysis to assess survival and to determine prognostic factors for bone survival (BS) in women with breast cancer and unstable SBM. Methods: A total population of 92 women with unstable SBM from breast cancer who were treated with RT at our department between January 2000 and January 2012 was retrospectively investigated. We calculated overall survival (OS) and BS (time between first diagnosis of bone metastases until death) with the Kaplan-Meier method and assessed prognostic factors for BS with a Cox regression model. Results: Mean age at first diagnosis of breast cancer was 60.8years±SD 12.4years. OS after 1, 2 and 5years was 84.8, 66.3 and 50%, respectively. BS after 1, 2 and 5years was 62.0, 33.7 and 12%, respectively. An age>50years (p