Does Competing Risk Analysis Give Useful Information About Endoprosthetic Survival in Extremity Osteosarcoma?

Abstract

Background Conventional survival analysis for endoprosthetic complications does not consider competing events adequately. Patients who die of their disease are no longer at risk for complications; therefore, death as a competing event may alter survivorship estimates in the orthopaedic-oncological setting. Questions/purposes This investigation aimed to compare (1) endoprosthetic survivorship after osteosarcoma by Kaplan-Meier analysis; and (2) by a competing risk model. Methods Between 1981 and 2009, we performed 247 modular endoprostheses for patients with extremity osteosarcoma; 73 patients had a followup of less than 2 years but all patients were included in statistical analysis. No patients were lost to followup for reasons other than death. Revision-free endoprosthetic survival until soft tissue failure (Type 1), aseptic loosening (Type 2), structural failure (Type 3), infection (Type 4), and local tumor progression (Type 5) was estimated according to a KaplanMeier analysis and a competing risk model. Sixty-four patients died throughout followup; the 5-and 10-year overall survival and metastasis-free survival were 72% and 70% and 70% and 69%, respectively. One hundred twentytwo patients (49%) had complications.

Revision Distal Femoral Arthroplasty With the Compress® Prosthesis Has a Low Rate of Mechanical Failure at 10 Years

“…At a median of 90 months (range, 24-181 months), the median MSTS score of the 21 patients who retained their implant was 27 (range, [24][25][26][27][28][29][30]). An active 90°arc of motion of the affected knee was maintained in 17 (81%) patients.…”

“…Given the risk of death from oncologic or associated causes in our patient population, a competing risk analysis was performed [25]. The cumulative incidence of all CPS implant failures was first calculated with death as a competing event, and failure was defined as removal of the spindle and anchor plug for any reason.…”

“…Three patients required secondary operations for cortical insufficiency proximal to the anchor plug in bone not spanned by the CPS implant and unrelated to the prosthesis. Median MSTS score was 27 (range, [24][25][26][27][28][29][30]. Conclusions Revision distal femoral replacement arthroplasty after a failed megaprosthesis is often difficult as a result of a lack of adequate bone.…”

Editorial: Estimating Survivorship in the Face of Competing Risks

“…The differences between KaplanMeier survivorship and a competingrisks estimate can be large [9], and some of the world's arthroplasty registries have begun to acknowledge this by employing a competing-risks approach in lieu of Kaplan-Meier statistics where appropriate [3]. But the differences are not always large.…”

CORR Insights®: Kaplan-Meier Survival Analysis Overestimates the Risk of Revision Arthroplasty: A Meta-analysis

“…In light of this, alternative analytic approaches that account for the occurrence of such competing events have been developed to estimate the cumulative incidence [1,8]. While these issues are mathematically demonstrated and have been illustrated in various medical domains [2,3,6], they have received less attention in orthopaedic research until recently [7,8]. But while some work has been done in individual datasets [8], to my knowledge, no study has taken a broader look at the influence of the phenomenon of competing risks on Kaplan-Meier survivorship estimates across orthopaedics more generally.…”