Epidemiology and Treatment of Metastatic Lesions Around the Elbow: A Systematic Review

Introduction: The elbow is a rare site for bone tumors, and for this reason, the literature provides little data on the epidemiology of metastatic lesions involving the distal humerus, proximal ulna, and radius. Before performing surgery of the metastatic bone, it is first necessary to consider both patients' and metastatic lesions' features in order to better choose the best possible treatment. This systematic review aims to collect data on elbow metastases, delineate primary tumors leading to such metastases, guide surgical treatment decisions, and evaluate reconstructive techniques and associated complications. Material and Methods: A systematic literature review was conducted in April 2024, searching the PubMed, MEDLINE, and Cochrane Library databases using specific search terms related to elbow metastases. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) was followed. Eligible studies reported at least one patient with metastatic bone disease involving the elbow region and specified the undertaken treatment. For studies reporting multiple skeletal sites, only elbow-specific data were extracted. We excluded recurrences of primary elbow tumors. The methodological quality of included studies was assessed with the modified Coleman Methodology Score (mCMS). Results: In total, 28 articles (103 patients) were included. The studies were predominantly case reports (68%), with a mean mCMS of 31. Gender was reported for only 41 patients: 71% were male and 29% female. The mean age at diagnosis of elbow metastatic lesion was 55 years old. Renal cell carcinoma was the most common primary tumor (28%), followed by breast (9%) and lung cancer (6%). The distal humerus was the most frequently affected site (85%). A surgical approach was adopted in 90% of cases, whereas 10% of patients were managed conservatively. Forty-five patients underwent wide tumor resection followed by reconstructive surgery while forty-eight patients received a surgical treatment for either pathological fractures or impending fractures. Conclusions: When treating elbow metastasis, a thorough evaluation of the patient is crucial, considering the patient's functional status, pain management needs, and overall prognosis; all these features influence the treatment of choice. The selected treatment should aim to provide optimal functional outcomes and minimize complications. For patients with pathological or impending fractures, single or double plate fixation is typically the preferred approach. For patients with severe, symptomatic lesions unresponsive to conservative therapy, resection followed by the implantation of a modular prosthesis usually offers the best clinical and functional outcomes.