Intentional Enneking-inappropriate surgery and high-energy particle therapy for unresectable osteogenic sarcoma of the spine: a retrospective study

OBJECTIVE The aim of this study was to compare the outcome of intralesional gross-total resection (GTR) followed by high-energy particle therapy with en bloc and intralesional resections. METHODS A retrospective study of patients diagnosed with primary osteogenic sarcoma (OGS) of the spine between 2009 and 2020 was conducted. Demographic information, including age, affected site, tumor volume, and Weinstein-Boriani-Biagini stage, was collected. Additionally, information on metastases at diagnosis, length of stay, operating time, complications, planned surgical treatment, and radiotherapy was also collected. Outcome measures, including local recurrence (LR) and disease-specific survival (DSS), were compared using Kaplan-Meier curves. RESULTS In total, 20 patients with a median age of 38 (IQR 23-60) years were included. The median follow-up was 15.7 (IQR 6.3-36.9) months. Eight patients underwent en bloc resection with a 38% (3 patients) LR rate and a median DSS of 26.4 months. Four patients received adjuvant high-energy particle therapy after planned GTR. Their median follow-up was 36 months; none of these patients experienced LR. Both the 1-year and 3-year DSSs were 100%. Another 8 patients underwent intralesional resection. Six of the 8 patients (75%) died of their disease, with a median survival of 7.3 (IQR 4.7-14) months. CONCLUSIONS GTR combined with adjuvant high-energy particle therapy appears to be a safe and effective alternative approach for patients with OGS of the spine when en bloc resection is not feasible. The results demonstrated a 3-year DSS of 100% and no major surgical complications.