Management of atypical cartilaginous tumors (ACT): an Italian Sarcoma Group (ISG) consensus document

Background Atypical cartilaginous tumors (ACT) are low-grade cartilaginous lesions of the appendicular skeleton with debated diagnostic and therapeutic management. Methods The Italian Sarcoma Group (ISG) conducted a multidisciplinary consensus process involving 61 experts from six specialties across 22 institutions. A narrative literature review informed key questions discussed during an in-person consensus meeting, and agreement was assessed through structured voting. Results Six consensus statements were developed: three on diagnosis, two on treatment, and one on active surveillance and follow-up. Biopsy was recommended selectively in the presence of aggressive or equivocal radiological features. Active surveillance was endorsed for selected patients, while intralesional curettage remains the preferred surgical option when treatment is indicated. Structured follow-up protocols were proposed. Conclusions This consensus provides practical recommendations for the management of ACT, supporting imaging-driven decision-making and active surveillance in appropriate cases.