Prognostic impact of oligometastases in orthopaedic surgery for metastatic bone disease

The rising number of cancer patients with metastatic bone disease (MBD) reflects advancements in treatment. The concept of oligometastatic disease, associated with improved prognosis, has emerged. This study evaluated prognostic factors, including oligometastases, in patients undergoing urgent orthopaedic surgery for MBD to inform preoperative decision-making and reduce morbidity and mortality from immobilization.

We retrospectively analysed records of patients who underwent surgery for MBD between 2005 and 2022. Data included medical history, tumour type, metastatic status, surgical method, lesion location, imaging, and survival outcomes. Multivariate survival analyses were conducted.

The number of metastases and presence of visceral metastases significantly influenced survival. Patients with single metastases had a median survival of 65 months, oligometastases 25 months, and polymetastases 11 months. Visceral metastases were associated with a median survival of 9 months versus 27 months without. Tumour type also impacted prognosis, with thyroid cancer patients having the highest median survival and lung cancer patients the lowest. Pathological fractures reduced survival significantly (11 months vs 36 months without fractures).

Oligometastatic disease is a strong prognostic factor for MBD patients undergoing orthopaedic surgery, with better outcomes compared to polymetastatic disease. Other key factors include tumour type, visceral metastases, and pathological fractures. Improved staging, risk assessment, and early interdisciplinary collaboration could mitigate pathological fractures and improve outcomes.