Primary osseous malignancies of the foot: a comprehensive literature review and insights from a single-centre experience

• Primary malignant bone tumors of the foot are exceptionally rare, leading to frequent diagnostic delays and under-recognition in clinical practice. • Osteosarcoma and Ewing sarcoma are the most prevalent subtypes, both in the literature and in our single-centre cohort. • A median diagnostic delay exceeding 6 months was observed, highlighting the need for increased clinical vigilance. • Amputation remains the most common surgical treatment, although limb-salvage may be possible in selected cases. • Oncologic outcomes are comparable to tumors in other skeletal sites when timely diagnosis and appropriate treatment are achieved. Primary malignant bone tumors of the foot are rare, with limited and heterogeneous data on. characteristics, management, and outcomes. This study aims to provide an overview of the epidemiology, treatment, and prognosis of these tumors through a systematic review and cohort analysis. PubMed, Embase, and Web of Science were searched for studies on osteosarcoma, Ewing’s sarcoma, and chondrosarcoma of the foot. Studies in English or German including ≥ 10 patients with original data were eligible. Demographic, clinical, treatment, and outcome data were extracted. Additionally, a retrospective review was performed of all patients with foot malignancies (chondrosarcoma, Ewing sarcoma or osteosarcoma) treated at Amsterdam UMC (2013–2024). Data were pooled for analysis. Eighteen studies met the inclusion criteria, comprising 884 patients including the single center cohort. Osteosarcoma, Ewing’s sarcoma, and chondrosarcoma were the most common malignancies, most frequently affecting the calcaneus, metatarsals, and phalanges, respectively. The median diagnostic delay was 9 (IQR 6–14) months, with pain and swelling as the predominant presenting symptoms. Below-knee amputation was the most common surgical procedure, particularly for hindfoot tumors. Local recurrence rates were highest in osteosarcoma (19%), while Ewing’s sarcoma had the highest incidence of metastatic disease (56%). Disease-specific mortality at last follow-up was 40% for osteosarcoma, 50% for Ewing’s sarcoma, and 21% for chondrosarcoma. The single-centre cohort mirrored these findings, highlighting the challenges of delayed diagnosis and inadvertent surgery. Primary malignant bone tumors of the foot present significant diagnostic and therapeutic challenges, with high rates of recurrence and metastasis. Early recognition, referral to specialized centers, and multidisciplinary management are essential to improve outcomes. Future research should focus on prospective data collection, standardized reporting, and patient-reported outcomes to guide optimal care.