ABSTRACT
PURPOSE: The purpose of this paper is to document the use of intravenous (IV) bisphosphonates for prevention of skeletal-related events (SREs) in patients with bone metastases (BM) due to breast cancer (BC), lung cancer (LC), or prostate cancer (PC). METHODS: Using data from two large US health systems, we identified all patients aged ≥ 18 years with primary BC, LC, or PC and newly diagnosed BM between 1/1/1995 and 12/31/2009. Starting with the diagnosis of BM, we reviewed medical and administrative records for evidence of receipt of IV bisphosphonates (zoledronic acid or pamidronate) and occurrence of SREs. Initiation of IV bisphosphonates prior to occurrence of an SRE was designated "primary prophylaxis"; use following an SRE was designated "secondary prophylaxis". RESULTS: We identified a total of 1,193 patients with newly diagnosed BM, including 400 with BC, 332 with LC, and 461 with PC. Use of IV bisphosphonates was substantially higher in BC (55.8 % of all patients) than in LC (14.8 %) or PC (20.2 %). Use of IV bisphosphonates was fairly evenly split between primary and secondary prophylaxis in BC (26.3 vs. 29.5 %, respectively) and PC (10.6 vs 9.5 %); in LC, however, primary prophylaxis was much less common than secondary prophylaxis (4.8 vs 9.9 %). CONCLUSIONS: Almost one half of all patients with BM due to BC, and substantially more with LC and PC, do not receive IV bisphosphonates. Among patients receiving such therapy, treatment often is not initiated until after the occurrence of an SRE. Our study suggests that IV bisphosphonates may be substantially underutilized in patients with BM due to these common cancers.
Subject(s)
Bone Density Conservation Agents/administration & dosage , Bone Neoplasms/drug therapy , Bone Neoplasms/secondary , Diphosphonates/administration & dosage , Imidazoles/administration & dosage , Aged , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Female , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Male , Middle Aged , Pamidronate , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Zoledronic AcidABSTRACT
PURPOSE: To document the risk of skeletal complications in patients with bone metastases from breast cancer (BC), lung cancer (LC), or prostate cancer (PC) in routine clinical practice. METHODS: We used data from two large US health systems to identify patients aged ≥18 years with primary BC, LC, or PC and newly diagnosed bone metastases between January 1, 1995 and December 31, 2009. Beginning with the date of diagnosis of bone metastasis, we estimated the cumulative incidence of skeletal-related events (SREs) (spinal cord compression, pathologic fracture, radiation to bone, bone surgery), based on review of medical records, accounting for death as a competing risk. RESULTS: We identified a total of 621 BC, 477 LC, and 721 PC patients with newly diagnosed bone metastases. SREs were present at diagnosis of bone metastasis in 22.4, 22.4, and 10.0 % of BC, LC, and PC patients, respectively. Relatively few LC or PC patients received intravenous bisphosphonates (14.8 and 20.2 %, respectively); use was higher in patients with BC, however (55.8 %). In BC, cumulative incidence of SREs during follow-up was 38.7 % at 6 months, 45.4 % at 12 months, and 54.2 % at 24 months; in LC, it was 41.0, 45.4, and 47.7 %; and in PC, it was 21.5, 30.4, and 41.9 %. More than one half of patients with bone metastases had evidence of SREs (BC: 62.6 %; LC: 58.7 %; PC: 51.7 %), either at diagnosis of bone metastases or subsequently. CONCLUSIONS: SREs are a frequent complication in patients with solid tumors and bone metastases, and are much more common than previously recognized in women with BC.
