Phase I/II, open, prospective clinical trial, historically controlled. The objective is to evaluate the safety and, as a secondary measure, the efficacy of an experimental treatment based on a cellular therapy (vaccination with autologous dendritic cells pulsed with tumor lysate) in patients affected of metastatic or relapsed sarcomas or (Central Nervous System) CNS tumors.

Phase I/II, open, prospective clinical trial, historically controlled. Patients affected of metastatic or relapsed sarcomas or (Central Nervous System) CNS tumors will be included. The patients will receive standard treatment and experimental treatment based on a cellular therapy with vaccination with autologous dendritic cells pulsed with tumor lysate. The immunization schedule includes 4 monthly vaccines, 4 bimonthly and quarterly remaining vaccines. The vaccines will be administered intradermally in combination with standard treatment for each type of tumor.

Inclusion Criteria:

• Signed informed consent
• Diagnosis or metastatic or relapsed sarcoma or high grade central nervous system tumor
• From 3 to 40 years
• Surgery feasibility. In the central nervous system tumors, residual tumor after surgery must be minimal.

Exclusion Criteria:

• Toxicity or liver, medullar, renal insufficiency that advise against participation
• Pregnant or breast feeding women
• Diagnosis of other tumor than basal cell squamous carcinoma of the skin or in situ cervix carcinoma
• Immunosuppressive treatment
• Human Immunodeficiency virus (HIV), hepatitis B, hepatitis C or syphilis infection