Background: The aim of the present study was to elucidate the details of bone metastasis (BM) and the resulting skeletal-related events (SREs), and survival and prognostic factors, in urothelial cancer (UC) patients with BM.
Methods: A total of 48 UC patients with BM who were treated at our institution between 1994 and 2013 were enrolled. Details of BM and SREs were investigated. The Kaplan-Meier method was used to estimate survival duration. Relationships between several clinical features and survival were analyzed using the log-rank test and the Cox hazard model.
Results: Of the 48 patients, 39 (81.3%) were male, with a median age at diagnosis of BM of 68 years [interquartile range (IQR), 61-75 years]. Frequent metastatic sites included the pelvis (31 patients, 64.6%) and spine (28, 58.3%). SREs occurred in 31 patients (64.6%) at a median duration of 0.9 months (IQR, 0.3-5.4 months) after diagnosis of BM, including radiation therapy (n = 23; 74.2%), spinal cord compression (n = 4; 12.9%), pathological fracture (n = 3; 9.7%) and hypercalcemia (n = 1; 3.2%). Median overall survival periods after diagnosis of BM and SREs were 6.2 and 5.6 months, respectively. On multivariate analysis, factors significantly associated with survival after BM were performance status [hazard ratio (HR) for ≥2 vs. 0-1, 4.94; P = 0.0003], liver metastasis (HR, 4.08; P = 0.0018), chemotherapy after BM (HR, 0.31; P = 0.0018), and use of bone-modifying agents (HR, 0.36; P = 0.0147).
Conclusions: We revealed clinicopathological factors that are predictive of prognosis of UC patients with BM. Although the prognosis is poor, chemotherapy and bone-modifying agents may confer survival benefits.
Keywords: Bone metastasis; Skeletal-related event; Urothelial cancer.