Multicenter and prospective phase II trial with gemcitabine and rapamycin in second line of metastatic osteosarcoma. The study includes 6 cycles of the combination gemcitabine+rapamycin in metastatic or unresectable osteosarcoma patients.

The trial seeks to analyze progression free survival (PFS), measured as PFS rate at 4 months, in patients with metastatic osteosarcoma who have previously received the most active drugs in this disease (methotrexate, cisplatin, adriamycin and ifosfamide). The treatment schedule consists of a maximum of 6 cycles of 3 weeks of gemcitabine+rapamycin. Gemcitabine is given at 800 mg/m2 in days 1 and 8 in cycles of 21 days. Rapamycin is given at 5 mg per day during treatment duration.

Inclusion Criteria:

• Informed consent signed before any trial test
• Age equal or less than 80 years
• Histological diagnosis of high-grade, metastatic or unresectable osteosarcoma in progression
• Previous treatment with drugs used in first line: methotrexate, adriamycin, platinum
• Measurable disease, acoording to RECIST criteria
• ECOG 0-2

Exclusion Criteria:

• Patients who have been irradiated on target lesions
• ECOG >2
• Bilirubin levels over normal values. Creatinine over 1.6 mg/dL
• History of other cancers except basal cell cancer or cervical cancer adequately treated
• Serious cardiovascular disease