151 endoprosthetic reconstructions for patients with primary tumors involving bone.

Abstract

As part of the UCLA limb salvage program, 151 patients received 151 endoprostheses for primary tumors involving bone. Follow-up of all patients was to death (56), revision (21), or a minimum two years for the 74 additional survivors (range: 24-114 months; mean: 52 months). Endoprosthetic replacements were of the distal femur (81), proximal femur (19), proximal humerus (13), proximal tibia (11), scapula (11), total femur (8), total humerus (4), intercalary prostheses (2), and one each of the distal humerus and the pelvis. There were three soft tissue sarcomas, five benign bone lesions, and 143 primary malignant tumors of bone. MSTS function was good-excellent in 78%. There were 64 local complications in 55 patients (36%). Mechanical failure occurred in 24 patients (15.9%), local recurrence occurred in ten (6.6%), minor wound healing problems in nine (5.9%), and infection in eight (5.3%). Few systemic complications were reported. Function appeared to be location dependent. All of the 29 patients with benign or low grade malignant tumors (parosteal, IA, IB) have survived. Of the 116 patients with stage IIA and IIB disease, 59% survived three years, and a Kaplan-Meier analysis projects that 56% are expected to survive at five years. Only 17 (11%) of these 151 endoprostheses have been revised; an additional four (3%) eventually came to amputation. The Kaplan-Meier analysis revealed that 91% of the prostheses survived three years and 83% survived five years. The Cox Proportional Hazards model revealed that for patients with stage IIA and IIB disease, the risk of death is four times the risk of the need for revision at five years. Although endoprosthetic reconstructions have their own unique complications, they have proven durable in this series of patients. Local problems usually can be managed without amputation, and patient satisfaction is high.