Infections of Tumor Prostheses: An Updated Review on Risk Factors, Microbiology, Diagnosis, and Treatment Strategies

SIMPLE SUMMARY: Tumor prostheses are associated with a high infection risk. The main pathogens involved in these infections include Staphylococcus spp., followed by Streptococcus spp. These pathogens usually form a biofilm that covers the implants, which is a matrix of extracellular polymeric substances containing sessile microbial cells connected to one another. Prompt diagnosis is challenging due to the highly varying clinical symptoms and the lack of specific preoperative and intraoperative diagnostic tests. However, the development of molecular biology techniques such as polymerase chain reaction (PCR)-based methods and next-generation sequencing (NGS) over the past decade has improved the diagnostic accuracy for periprosthetic infections. Despite their high sensitivity, these methods have a high rate of false positive results. Surgical management with one- or two-stage revision surgery is mandatory for eradication of these infections. This study consolidates the current knowledge regarding the risk factors, microbiology, diagnosis, and treatment of infections of tumor prostheses. ABSTRACT: Several causes contribute to the high infection rate in tumor prostheses, including extensive tissue dissection and patients’ immunosuppression due to the neoplastic disease. Most of these infections develop within the first 2 years following surgery with 70% of them occurring during the first year, while they are often associated with a low pathogen burden. The pathogenesis of infections in tumor prostheses is linked to bacteria developing in biofilms. Approximately half of them are caused by Staphylococcus spp., followed by Streptococcus spp., Enterococcus spp., and Enterobacteriaceae spp., while multiple pathogens may be isolated in up to 25% of the cases, with coagulase-negative Staphylococci (CoNS) and Enterococccus spp. being the most frequent pair. Although early detection and timely management are essential for complete resolution of these challenging infections, prompt diagnosis is problematic due to the highly varying clinical symptoms and the lack of specific preoperative and intraoperative diagnostic tests. Surgical management with one- or two-stage revision surgery is the mainstay for successful eradication of these infections. The recent advances in laboratory diagnostics and the development of biofilm-resistant prostheses over the past years have been areas of great interest, as research is now focused on prevention strategies. The aim of this study is to review and consolidate the current knowledge regarding the epidemiology, risk factors, microbiology, and diagnosis of infections of tumor prostheses, and to review the current concepts for their treatment and outcomes.