After standard multimodal therapy, the prognosis of relapsed and unresectable high-grade osteosarcoma is dismal and unchanged over the last decades. Recently, mitogen-activated protein kinases were shown to be activated in osteosarcoma specimens, suggesting, therefore, they are suitable targets for the multikinase inhibitor sorafenib. Thus, we explored sorafenib activity in patients with relapsed and unresectable osteosarcoma. Patients >14 years, progressing after standard treatment, were eligible to receive 400 mg of sorafenib twice daily until progression or unacceptable toxicity. The primary end point was progression-free survival (PFS) at 4 months. Secondary objectives were PFS, overall survival (OS), clinical benefit rate (CBR), defined as no progression at 6 months and safety. This nonrandomized phase II study used a Simon two-stage design. PFS and OS at 95% confidence intervals (95% CIs) were calculated by the Kaplan–Meier method. All tests were two sided. Thirty-five patients were enrolled. PFS at 4 months was 46% (95% CI 28% to 63%). Median PFS and OS were 4 (95% CI 2–5) and 7 (95% CI 7–8) months, respectively. The CBR was 29% (95% CI 13% to 44%). We observed 3 (8%) partial responses (PRs), 2 (6%) minor responses (<30% tumor shrinkage) and 12 (34%) stable diseases (SDs). For six patients (17%), PR/SD lasted ≥6 months. Noteworthy, tumor density reduction and [¹⁸F]2-fluoro-2-deoxy-d-glucose–positron emission tomography responses were observed among SD patients. Sorafenib was reduced or briefly interrupted in 16 (46%) patients and permanently discontinued in one (3%) case due to toxicity. Sorafenib demonstrated activity as a second- or third-line treatment in terms of PFS at 4 months with some unprecedented long-lasting responses. Sorafenib, the first targeted therapy showing activity in osteosarcoma patients, deserves further investigations.

Results of previous study showed promising but short-lived activity of sorafenib in the treatment of patients with unresectable advanced and metastatic osteosarcoma. This treatment failure has been attributed to the mTOR pathway and might therefore be overcome with the addition of mTOR inhibitors. We aimed to investigate the activity of sorafenib in combination with everolimus in patients with inoperable high-grade osteosarcoma progressing after standard treatment. We did this non-randomised phase 2 trial in three Italian Sarcoma Group centres. We enrolled adults (≥18 years) with relapsed or unresectable osteosarcoma progressing after standard treatment (methotrexate, cisplatin, and doxorubicin, with or without ifosfamide). Patients received 800 mg sorafenib plus 5 mg everolimus once a day until disease progression or unacceptable toxic effects. The primary endpoint was 6 month progression-free survival (PFS). All analyses were intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT01804374. We enrolled 38 patients between June 16, 2011, and June 4, 2013. 17 (45%; 95% CI 28-61) of 38 patients were progression free at 6 months. Toxic effects led to dose reductions, or short interruptions, or both in 25 (66%) of 38 patients and permanent discontinuation for two (5%) patients. The most common grade 3-4 adverse events were lymphopenia and hypophosphataemia each in six (16%) patients, hand and foot syndrome in five (13%), thrombocytopenia in four (11%), and fatigue, oral mucositis, diarrhoea, and anaemia each in two (5%). One patient (3%) had a grade 3 pneumothorax that required trans-thoracic drainage, and that recurred at the time of disease progression. This was reported as a serious adverse event related to the study drugs in both instances. No other serious adverse events were reported during the trial. There were no treatment-related deaths. Although the combination of sorafenib and everolimus showed activity as a further-line treatment for patients with advanced or unresectable osteosarcoma, it did not attain the prespecified target of 6 month PFS of 50% or greater. Italian Sarcoma Group.

Purpose: To identify factors that influence postrelapse survival (PRS) in patients with nonmetastatic osteosarcoma of the extremity Patients and Methods: One hundred sixty-two patients with recurrent osteosarcoma of the extremity were retrospectively reviewed. The first-line treatment included surgery of the primary lesion and chemotherapy with methotrexate, doxorubicin, cisplatin, and ifosfamide. Results: The projected 5-year PRS rate was 28%. Patients who had complete surgery of recurrence had a 5-year PRS of 39%, whereas for those who did not have complete surgery, PRS was 0% at 3 years (P < .0001). In the latter group, PRS was not influenced by site of recurrence and relapse-free interval (RFI), although it was influenced (P = .006) by the use of second-line chemotherapy (PRS, 53% at 12 months for patients who received chemotherapy v 12% for those who did not). In patients who had complete surgery, PRS was influenced by site of relapse (5-year PRS, lung 44%, other 19%; P < .06), RFI (5-year PRS at ≤ 24 months, 20%; at > 24 months, 60%; P < .0001), and number of lung metastases (5-year PRS, two or fewer nodules, 59%; more than two nodules, 14%; P < .0001) but not by the use of a second-line chemotherapy treatment. Conclusion: RFI, site of metastases, and number of pulmonary nodules are the main prognostic factors for PRS in osteosarcoma. Complete surgery of recurrence is pivotal in the strategy of treatment. Patients with unresectable recurrence benefit from second-line chemotherapy, whereas our data do not support a generalized use of chemotherapy after complete surgery of first recurrence.