Perioperative management of antirheumatic medications in adults with rheumatoid arthritis (RA) undergoing orthopedic surgery requires balancing postoperative infection and impaired wound healing against disease flare, pain, and delayed rehabilitation. This systematic review aimed to evaluate how perioperative continuation, withholding, interruption timing, restart timing, dose modification, or exposure to antirheumatic medications relates to postoperative outcomes in adults with RA undergoing arthroplasty and non-arthroplasty orthopedic procedures. PubMed, Scopus, and the Cochrane Central Register of Controlled Trials were searched from database inception to 18 April 2026 for English-language full-text clinical studies. The primary outcomes were surgical site infection/periprosthetic joint infection, delayed wound healing, and postoperative RA flare. Secondary outcomes included reoperation, revision, readmission, mortality, venous thromboembolism, dislocation, and other procedure-specific complications. Original studies were classified as direct perioperative strategy evidence, medication-exposure evidence, or supportive clinical-context evidence. Forty-three original clinical studies were included, together with six non-original contextual sources. The evidence was predominantly observational, clinically heterogeneous, and of very low certainty. Methotrexate continuation was not associated with an evident increase in early postoperative complications, whereas direct evidence for other conventional synthetic agents was limited. Longer interruption of biologic or targeted synthetic therapy did not consistently reduce infection or wound-healing complications, while several studies associated treatment interruption with postoperative flare. Chronic baseline glucocorticoid exposure was associated with adverse outcomes but was clinically distinct from short-term perioperative administration; stress-dose supplementation was not directly evaluated. Medication decisions should therefore be individualized according to drug class, disease control, glucocorticoid burden, surgical procedure, and patient risk profile.

Background: Bone and soft-tissue sarcomas are rare, heterogeneous malignancies whose surveillance remains dominated by imaging despite substantial molecular diversity and variable patterns of relapse. Circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs) offer minimally invasive approaches for monitoring tumor biology, but their performance in sarcoma depends strongly on subtype, disease burden, assay design, and biological shedding. Methods: This narrative review synthesizes evidence published from 2015 to 2026 on ctDNA and CTCs for baseline risk assessment, treatment-response monitoring, minimal residual disease (MRD) detection, molecular relapse, and integration with imaging-based surveillance in bone and soft-tissue sarcomas. Results: Current evidence supports a genomics-guided framework in which liquid-biopsy strategy is selected according to sarcoma subtype, molecular architecture, and clinical purpose. ctDNA is the most mature analyte, with best-supported evidence in osteosarcoma, where tumor-informed assays predict postoperative relapse, and in translocation-associated sarcomas, where breakpoint-guided assays enable highly specific longitudinal monitoring. Copy-number-based approaches are relevant for complex-karyotype tumors, while mutation-, methylation-, fragmentomic-, and RNA-based strategies may be useful in selected contexts. However, detection rates vary, false-negative results occur in low-shedding or low-volume disease, and clinical utility for changing treatment remains incompletely established. CTCs provide complementary cellular and prognostic information, particularly in osteosarcoma, but remain limited by platform heterogeneity and incomplete standardization. Conclusion: Liquid biopsy may refine risk stratification, support treatment-response assessment, clarify indeterminate imaging findings, and identify molecular relapse in selected sarcoma patients. At present, it should be interpreted as an adjunct to imaging and specialist multidisciplinary care rather than as a replacement for standard radiologic surveillance.